JP2008203976A - Air pocket generation simulation method in immersion-processed object and computer-executable program executing simulation method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To accurately simulate an air pocket generated in an immersion-processed object even in the immersion-processed object provided in a such state that another member is put inside one member. <P>SOLUTION: A hemispheric surface (S) covering a component (P_i) is generated, an attribute of a free edge mesh (FM_1) appearing when viewed from the hemispheric surface (S) is set as a liquid, the free edge mesh (FM_1) is set as an initial boundary mesh, and an attribute of a successive adjacent mesh is analyzed from the initial boundary mesh. Accordingly, even if setting the component (P_i) provided in such a state that a partition member is put inside a box-like member as an analysis target, a free edge mesh (FM_2) of the partition member is not set as the initial boundary mesh, and the air pocket generated in the component (P_i) can be accurately simulated. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an air pool generation simulation method for an object to be immersed that simulates an air pool generated in an object to be immersed when immersed in a paint tank, and a program executable by a computer that executes the simulation method.

  An object to be dipped such as a vehicle body of a vehicle is dipped in a paint tank filled with a liquid paint so that the surface thereof is electrodeposited. According to such a coating method, the thickness of the coating film formed on the surface of the object to be immersed can be made substantially uniform, or a similar coating process can be applied to the welded portion of the object to be immersed. There are advantages such as. On the other hand, for example, in the case of a vehicle body, a plurality of concave portions are formed on the inner surface of the hood, the inner surface of the roof, the lower surface of the floor, etc., so that the concave portion becomes an air pocket called an air pocket. In the state where the air in the air pool remains, there is a drawback that the portion cannot be painted.

  Therefore, for example, as shown in Patent Document 1, a discharge path for discharging air into the atmosphere is formed in advance in the object to be immersed so as not to cause air accumulation in the object to be immersed. Air is discharged into the atmosphere through a discharge path so that the entire surface of the object to be immersed can be subjected to a coating process.

  In general, the air pool generated in the object to be immersed can be simulated by using a well-known analysis method using a free surface, and the simulation result is reflected in the design of the object to be immersed. Work efficiency can be improved. The present applicant has applied for the simulation methods shown in Japanese Patent Application Nos. 2006-180453 and 2005-330098 in order to shorten the time required for the simulation and further improve the efficiency of the design work.

Among the simulation methods, the former (Japanese Patent Application No. 2006-180453) divides the numerical calculation model of the object to be immersed into two-dimensional elements without dividing them into three-dimensional elements. The generation of air pockets is simulated using a numerical calculation model of the object to be immersed formed. The latter (Japanese Patent Application No. 2005-330098) generates a numerical calculation model by arranging a plurality of nodes on the surface of the object to be immersed, and simulates the occurrence of air pockets using the coordinate data of each node. ing. In both the former and the latter cases, the load on the computer is reduced by using the data forming the two-dimensional elements and the coordinate data of the nodes, and as a result, the time required for the simulation can be shortened. .
Japanese Patent Laid-Open No. 10-045037

  However, according to each of the simulation methods described above, since the occurrence of air accumulation is simulated for each of a plurality of members forming the object to be immersed, the immersion process formed by connecting a plurality of members. An accurate simulation result could not be obtained with an object as an analysis target.

  That is, for example, an object to be treated (see FIGS. 2 and 3) in which a partition member is provided inside a box-shaped member having an opening is applied to the paint so that the opening of the object to be treated is directed downward. When immersed in a tank, an air pool is actually generated inside the box-shaped member, and the periphery of the partition member is filled with air. However, according to each of the simulation methods described above, the analysis processing is executed individually for each member, that is, for each of the box-shaped member and the partition member, so that the attributes of all elements (or all nodes) forming the partition member are It is erroneously determined as paint (liquid).

  An object of the present invention is to immerse an object to be accurately immersed in an object to be immersed, even if it is an object to be immersed in which another member is inserted inside one member. It is an object of the present invention to provide a method for simulating the occurrence of air accumulation and a computer-executable program for executing the simulation method.

  The method for simulating the occurrence of air stagnation in an object to be immersed in the present invention is a method for simulating the occurrence of air stagnation in an object to be immersed in the object to be processed for simulating an air stagnation generated in the object to be immersed in immersion in a paint tank. A first step of dividing the shape data of the immersion treatment product into a plurality of two-dimensional elements to construct a numerical calculation model, and a second step of extracting a free edge element that forms an end or a hole of the numerical calculation model A third step of generating a hemispherical model that covers the numerical calculation model from the opposite side of the direction of gravity of the numerical calculation model, and when the numerical calculation model is viewed from the hemispherical model, A fourth step of determining whether or not a free edge element is visible, and the free edge element is visible in the fourth step. After determining, the attribute of the free edge element is set to paint, the fifth step of setting the free edge element as the initial boundary element, and the element sharing the node with the initial boundary element is set as the adjacent element A sixth step of analyzing the adjacent element set in the sixth step using the initial boundary element, and setting an attribute of the adjacent element based on the analysis result; An eighth step of setting the adjacent element that has been analyzed in the seventh step as a secondary boundary element, and setting an element that shares a node with the secondary boundary element as an adjacent element; and the eighth step Analyzing the adjacent element set in step 2 using the secondary boundary element, and setting an attribute of the adjacent element based on the analysis result; and the secondary boundary It is determined whether there is an adjacent element adjacent to the element, and if it is determined that there is an adjacent element adjacent to the secondary boundary element, the first element is continued until there is no adjacent element adjacent to the secondary boundary element. And a tenth step of repeating the process of each step in the order of step 8 and the ninth step, and ending the analysis when it is determined that there is no adjacent element adjacent to the secondary boundary element. Features.

  In the method for simulating the occurrence of air accumulation in the object to be immersed according to the present invention, in the fourth step, a direction vector extending from the hemispherical model toward the free edge element is generated, and directly with the free edge element. It is determined whether or not it intersects, and when it is determined that the free edge element directly intersects, the free edge element can be seen.

  The method for simulating the occurrence of air stagnation in an object to be immersed in the present invention is a method for simulating the occurrence of air stagnation in an object to be immersed in the object to be processed for simulating an air stagnation generated in the object to be immersed in immersion in a paint tank. A first step of dividing the shape data of the immersion treatment product into a plurality of two-dimensional elements to construct a numerical calculation model, and a second step of extracting a free edge element that forms an end or a hole of the numerical calculation model A third step of setting a hemispherical representative point solid angle range on the side opposite to the direction of gravity of the numerical calculation model at the representative point of the free edge element, and from the representative point of the free edge element A fourth step of determining whether or not the numerical calculation model is visible when looking up within the representative point solid angle range; After determining that the numerical calculation model is not visible in the step, a fifth step of setting the attribute of the free edge element to paint and setting the free edge element as an initial boundary element; and the initial boundary element; A sixth step of setting an element sharing a node as an adjacent element, and analyzing the adjacent element set in the sixth step using the initial boundary element, and based on the analysis result, A seventh step of setting an attribute, and the adjacent element analyzed in the seventh step is set as a secondary boundary element, and an element sharing a node with the secondary boundary element is set as an adjacent element 8 and the adjacent element set in the eighth step are analyzed using the secondary boundary element, and the adjacent element is analyzed based on the analysis result. And determining whether there is an adjacent element adjacent to the secondary boundary element, and determining that there is an adjacent element adjacent to the secondary boundary element, When the process of each step is repeated in the order of the eighth step and the ninth step until there is no adjacent element adjacent to the secondary boundary element, and it is determined that there is no adjacent element adjacent to the secondary boundary element Comprises a tenth step for terminating the analysis.

  In the method for simulating the occurrence of air accumulation in the object to be immersed according to the present invention, in the fourth step, a direction vector extending from a representative point of the free edge element is generated and whether or not it intersects with the numerical calculation model. When it is determined that the numerical calculation model does not intersect with the numerical calculation model, the numerical calculation model can be seen.

  In the method of simulating the occurrence of air accumulation in the object to be immersed according to the present invention, in the third step, a normal vector extending from a representative point of the free edge element is further generated, and the normal vector has a top portion. Performing a step of setting a penetrating hemispherical normal vector solid angle range and a step of setting a common solid angle range that is the representative point solid angle range and the normal vector solid angle range; In the step, the determination is made based on the common solid angle range instead of the representative point solid angle range.

  In the method of simulating the occurrence of air accumulation in the object to be immersed according to the present invention, in the fifth step, the representative point height of the free edge of the numerical calculation model in the horizontal position is compared with the representative point height of the free edge element. And, when the representative point height of the free edge is higher than or equal to the representative point height of the free edge element, the attribute of the free edge element is set to paint, The free edge element is set as an initial boundary element.

  In addition to the tenth step, the method for simulating the occurrence of air accumulation in the object to be immersed according to the present invention extracts the free edge element forming the free edge of the numerical calculation model at a horizontal position from the free edge element. And an eleventh step of correcting the attribute of the free edge element according to the attribute of the adjacent element in the extracted free edge element.

  The method for simulating the occurrence of air stagnation in an object to be immersed in the present invention is a method for simulating the occurrence of air stagnation in an object to be immersed in the object to be processed for simulating an air stagnation generated in the object to be immersed in immersion in a paint tank. A first step of constructing a numerical calculation model by arranging a plurality of nodes on the surface of the shape data of the immersion treatment product, and a second step of extracting a free edge node forming an end or a hole of the numerical calculation model A third step of generating a hemispherical model that covers the numerical calculation model from a side opposite to the direction of gravity of the numerical calculation model, and the free calculation when the numerical calculation model is viewed from the hemispherical model. A fourth step of determining whether an edge node is visible, and the free edge node is visible in the fourth step After the determination, the fifth step of setting the attribute of the free edge node to paint and setting the free edge node as an initial node and the sixth step of setting a node adjacent to the initial node as an adjacent node And analyzing the adjacent node set in the sixth step using the initial node, and setting the attribute of the adjacent node based on the analysis result, and in the seventh step The adjacent node that has been analyzed is set as a secondary node, an eighth step of setting a node adjacent to the secondary node as an adjacent node, and the adjacent node set in the eighth step as the second node. Analyzing using the next node, and determining whether there is an adjacent node adjacent to the secondary node, and a ninth step of setting the attribute of the adjacent node based on the analysis result If it is determined that there is an adjacent node adjacent to the secondary node, the process of each step is performed in the order of the eighth step and the ninth step until there is no adjacent node adjacent to the secondary node. It is repeated, and when it is determined that there is no adjacent node adjacent to the secondary node, a tenth step of ending the analysis is provided.

  In the method for simulating the occurrence of air accumulation in the object to be immersed according to the present invention, in the fourth step, a direction vector extending from the hemispherical model toward the free edge node is generated and directly connected to the free edge node. It is determined whether or not to intersect, and when it is determined to directly intersect with the free edge node, the free edge node can be seen.

  The method for simulating the occurrence of air stagnation in an object to be immersed in the present invention is a method for simulating the occurrence of air stagnation in an object to be immersed in the object to be processed for simulating an air stagnation generated in the object to be immersed in immersion in a paint tank. A first step of constructing a numerical calculation model by arranging a plurality of nodes on the surface of the shape data of the immersion treatment product, and a second step of extracting a free edge node forming an end or a hole of the numerical calculation model A step, a third step of setting a hemispherical solid angle range on the opposite side of the gravitational direction of the numerical model from the free edge node, and when looking up in the solid angle range from the free edge node A fourth step of determining whether or not the numerical calculation model is visible; and the numerical calculation model in the fourth step. 5) to set the attribute of the free edge node to paint, and to set the free edge node as the initial node, and to set the node adjacent to the initial node as the adjacent node A sixth step of analyzing the adjacent node set in the sixth step using the initial node, and setting an attribute of the adjacent node based on the analysis result, The adjacent node that has been analyzed in the seventh step is set as a secondary node, an eighth step in which a node adjacent to the secondary node is set as an adjacent node, and the set in the eighth step There is a ninth step of analyzing adjacent nodes using the secondary nodes and setting the attributes of the adjacent nodes based on the analysis results, and adjacent nodes adjacent to the secondary nodes. And when it is determined that there is an adjacent node adjacent to the secondary node, the eighth step and the ninth step are repeated until there is no adjacent node adjacent to the secondary node. And a tenth step of ending the analysis when it is determined that there is no adjacent node adjacent to the secondary node.

  In the method for simulating the occurrence of air accumulation in the object to be immersed according to the present invention, in the fourth step, a direction vector extending from the free edge node is generated, and it is determined whether or not it intersects with the numerical calculation model. The numerical calculation model can be seen when it is determined that the numerical calculation model does not intersect with the numerical calculation model.

  In the fifth step, the method for simulating the occurrence of air accumulation in the object to be immersed according to the present invention includes the height of the node on the free edge of the numerical calculation model in the horizontal position and other than on the free edge adjacent to the node. If the height of a node on the free edge is higher than or equal to the height of a node other than the free edge, the height on the free edge The node attribute is set to paint, and the node on the free edge is set as an initial boundary element.

  In addition to the tenth step, the method for simulating the occurrence of air accumulation in an object to be immersed according to the present invention extracts the free edge node forming the free edge of the numerical calculation model at a horizontal position from the free edge node. And an eleventh step of correcting the attribute of the free edge node according to the attribute of the adjacent node of the extracted free edge node.

  In the method for simulating the occurrence of air accumulation in the object to be immersed according to the present invention, the object to be immersed is a vehicle body.

  The computer-executable program for executing the method for simulating the occurrence of air stagnation in the object to be immersed according to the present invention is an air stagnation in the object to be immersed that simulates the air stagnation generated in the object to be immersed when immersed in the paint tank. A computer-executable program for executing a generation simulation method, the first step of constructing a numerical calculation model by dividing the shape data of the object to be immersed into a plurality of two-dimensional elements, and the numerical calculation A second step of extracting a free edge element forming an end portion or a hole of the model, and a third step of generating a hemispherical model covering the numerical calculation model from a side opposite to a direction of gravity of the numerical calculation model When the numerical calculation model is viewed from the hemispherical model, the free edge element is visible. A fourth step of determining whether or not the free edge element is visible in the fourth step, and setting an attribute of the free edge element to paint, and setting the free edge element to an initial boundary element Using the initial boundary element, the sixth step of setting an element that shares a node with the initial boundary element as an adjacent element, and the adjacent element set in the sixth step using the initial boundary element A second step of setting the attribute of the adjacent element based on the analysis result, and setting the adjacent element analyzed in the seventh step as a secondary boundary element. An eighth step of setting an element sharing a node with the element as an adjacent element, and using the secondary boundary element as the adjacent element set in the eighth step Analyzing, determining whether there is an adjacent element adjacent to the secondary boundary element, and determining whether there is an adjacent element adjacent to the secondary boundary element. If it is determined that there is an adjacent element, the process of each step is repeated in the order of the eighth step and the ninth step until there is no adjacent element adjacent to the secondary boundary element, and the secondary boundary And a tenth step of ending the analysis when it is determined that there is no adjacent element adjacent to the element.

  The computer-executable program for executing the method for simulating the occurrence of air accumulation in the object to be immersed according to the present invention generates a direction vector extending from the hemispherical model toward the free edge element in the fourth step. In addition, it is determined whether or not it directly intersects with the free edge element, and when it is determined that it intersects directly with the free edge element, the free edge element can be seen.

  The computer-executable program for executing the method for simulating the occurrence of air stagnation in the object to be immersed according to the present invention is an air stagnation in the object to be immersed that simulates the air stagnation generated in the object to be immersed when immersed in the paint tank. A computer-executable program for executing a generation simulation method, the first step of constructing a numerical calculation model by dividing the shape data of the object to be immersed into a plurality of two-dimensional elements, and the numerical calculation A second step of extracting a free edge element forming an end or a hole of the model, and a hemispherical representative point solid angle on the opposite side of the gravitational direction of the numerical model at the representative point of the free edge element A third step of setting a range, and the representative point solid angle range from the representative point of the free edge element A fourth step of determining whether or not the numerical calculation model can be seen when looking up, and determining that the numerical calculation model is not visible in the fourth step, and then setting the attribute of the free edge element as a paint In the fifth step, the fifth step of setting the free edge element as an initial boundary element, the sixth step of setting an element sharing a node with the initial boundary element as an adjacent element, and the sixth step A seventh step of analyzing the set adjacent element using the initial boundary element, and setting an attribute of the adjacent element based on the analysis result; and the adjacent element for which analysis has been completed in the seventh step Is set as a secondary boundary element, and an element sharing a node with this secondary boundary element is set as an adjacent element; and in the eighth step, There is a ninth step of analyzing the determined adjacent element using the secondary boundary element, and setting an attribute of the adjacent element based on the analysis result, and an adjacent element adjacent to the secondary boundary element And when it is determined that there is an adjacent element adjacent to the secondary boundary element, the eighth step and the ninth step are performed until there is no adjacent element adjacent to the secondary boundary element. And a tenth step of ending the analysis when it is determined that there is no adjacent element adjacent to the secondary boundary element.

  The computer-executable program for executing the method for simulating the occurrence of air accumulation in the object to be immersed according to the present invention generates a direction vector extending from a representative point of the free edge element in the fourth step, and It is determined whether or not it intersects with the numerical calculation model, and when it is determined that it does not intersect with the numerical calculation model, the numerical calculation model can be seen.

  In the third step, the computer-executable program for executing the method for simulating the occurrence of air accumulation in the object to be immersed according to the present invention further includes a step of generating a normal vector extending from a representative point of the free edge element. And a step of setting a hemispherical normal vector solid angle range through which the normal vector penetrates the top, and a step of setting a common solid angle range that is the representative point solid angle range and the normal vector solid angle range. And in the fourth step, the determination is made based on the common solid angle range instead of the representative point solid angle range.

  The computer-executable program for executing the method for simulating the occurrence of air accumulation in the object to be immersed according to the present invention includes, in the fifth step, the representative point height of the free edge of the numerical calculation model in the horizontal position, and the free point. The free edge element is compared with the representative point height of the edge element, and the representative point height of the free edge is higher than or equal to the representative point height of the free edge element. Are set to paint, and the free edge element is set to an initial boundary element.

  The computer-executable program for executing the method for simulating the occurrence of air accumulation in the object to be immersed according to the present invention includes a free edge of the numerical calculation model in a horizontal position from the free edge element in addition to the tenth step. The free edge element is extracted, and the attribute of the free edge element is modified according to the attribute of the adjacent element in the extracted free edge element.

  The computer-executable program for executing the method for simulating the occurrence of air stagnation in the object to be immersed according to the present invention is an air stagnation in the object to be immersed that simulates the air stagnation generated in the object to be immersed when immersed in the paint tank. A computer-executable program for executing a generation simulation method, the first step of constructing a numerical calculation model by arranging a plurality of nodes on the surface of the shape data of the object to be immersed, and the numerical calculation model A second step of extracting a free edge node that forms an end portion or a hole portion of the first calculation unit; and a third step of generating a hemispherical model that covers the numerical calculation model from a side opposite to the direction of gravity of the numerical calculation model; When the numerical calculation model is viewed from the hemispherical model, the free edge node is visible After determining whether or not the free edge node is visible in the fourth step and determining whether or not the free edge node is visible in the fourth step, the attribute of the free edge node is set to paint and the free edge node is set to the initial node A fifth step of performing, a sixth step of setting a node adjacent to the initial node as an adjacent node, and analyzing the adjacent node set in the sixth step using the initial node. A seventh step of setting the attribute of the adjacent node based on the result, the adjacent node analyzed in the seventh step being set as a secondary node, and the node adjacent to the secondary node is set as an adjacent node And the adjacent node set in the eighth step is analyzed using the secondary node, and the adjacent node is analyzed based on the analysis result. A ninth step of setting an attribute of a node; whether or not there is an adjacent node adjacent to the secondary node; and if it is determined that there is an adjacent node adjacent to the secondary node, The process of each step is repeated in the order of the eighth step and the ninth step until there is no adjacent node adjacent to the next node, and analysis is performed when it is determined that there is no adjacent node adjacent to the secondary node. And a tenth step of ending the process.

  The computer-executable program for executing the method for simulating the occurrence of air accumulation in the object to be immersed according to the present invention generates, in the fourth step, a direction vector extending from the hemispherical model toward the free edge node. In addition, it is determined whether or not it directly intersects with the free edge node, and when it is determined that the free edge node directly intersects, the free edge node can be seen.

  The computer-executable program for executing the method for simulating the occurrence of air stagnation in the object to be immersed according to the present invention is an air stagnation in the object to be immersed that simulates the air stagnation generated in the object to be immersed when immersed in the paint tank. A computer-executable program for executing a generation simulation method, the first step of constructing a numerical calculation model by arranging a plurality of nodes on the surface of the shape data of the object to be immersed, and the numerical calculation model A second step of extracting a free edge node that forms an end or a hole portion of the object, and a third step of setting a hemispherical solid angle range from the free edge node to the side opposite to the gravitational direction of the numerical model. The numerical calculation when looking up in the solid angle range from the free edge node A fourth step for determining whether or not Dell is visible; and after determining that the numerical calculation model is not visible in the fourth step, the attribute of the free edge node is set to paint, and the free edge node Using the initial node, the sixth step of setting the node adjacent to the initial node as the adjacent node, the sixth step of setting the node adjacent to the initial node as the adjacent node, and the adjacent node set in the sixth step using the initial node Analyzing, setting the attribute of the adjacent node based on the analysis result, and setting the adjacent node analyzed in the seventh step as a secondary node and adjacent to the secondary node An eighth step of setting a node to be set as an adjacent node, and the adjacent node set in the eighth step is analyzed using the secondary node. And when determining whether there is an adjacent node adjacent to the secondary node and determining that there is an adjacent node adjacent to the secondary node. Repeats the processing of each step in the order of the eighth step and the ninth step until there is no adjacent node adjacent to the secondary node, and determines that there is no adjacent node adjacent to the secondary node. In some cases, the method includes a tenth step of terminating the analysis.

  The computer-executable program for executing the method for simulating the occurrence of air accumulation in the object to be immersed according to the present invention generates a direction vector extending from the free edge node in the fourth step, and the numerical calculation model It is determined whether the numerical calculation model can be seen when it is determined that the numerical calculation model does not intersect with the numerical calculation model.

  The computer-executable program for executing the method for simulating the occurrence of air accumulation in the object to be immersed according to the present invention includes, in the fifth step, the height of the node on the free edge of the numerical calculation model in the horizontal position, The height of a node on the free edge adjacent to the node is compared with the height of the node other than on the free edge, and the height of the node on the free edge is higher than or equal to the height of the node on the free edge. In this case, the attribute of the node on the free edge is set to the paint, and the node on the free edge is set to the initial boundary element.

  The computer-executable program for executing the method for simulating the occurrence of air stagnation in the object to be immersed according to the present invention includes a free edge of the numerical calculation model in a horizontal position from the free edge nodes in addition to the tenth step. And extracting the free edge nodes that form, and modifying the attributes of the free edge nodes according to the attributes of the adjacent nodes of the extracted free edge nodes.

  The computer-executable program for executing the simulation method for generating air stagnation in the object to be immersed according to the present invention is characterized in that the object to be immersed is a vehicle body.

  According to the method for simulating the occurrence of air accumulation in an object to be immersed according to the present invention, a hemispherical model that covers the numerical calculation model is generated from the side opposite to the gravity direction of the numerical calculation model, and the numerical calculation model is viewed from this hemispherical model. The attribute of the free edge element (node) that is sometimes visible is used as paint, and the free edge element (node) is set as the initial boundary element (initial node), and the elements adjacent to each other from the initial boundary element (initial node) The attribute of (node) can be analyzed. Therefore, even if an object to be immersed in which another member enters inside one member is set as an analysis target, the free edge element (node) of the other member is set as an initial boundary element (initial node). Therefore, it is possible to accurately simulate the air pool generated in the object to be immersed.

  According to the invention of the method for simulating the occurrence of air accumulation in the object to be immersed according to the present invention, does the direction vector extending from the hemispherical model toward the free edge element (node) directly intersect the free edge element (node)? It can be determined whether or not it can be seen by determining whether or not. Accordingly, it is possible to determine whether or not the image is visible using the coordinate data of the free edge element (node).

  According to the method for simulating the occurrence of air accumulation in the object to be immersed according to the present invention, it is determined whether or not the numerical calculation model can be seen when looking up within the solid angle range from the free edge element (node) of the numerical calculation model. When it is determined that the calculation model cannot be seen, the attribute of the free edge element (node) is set to the paint and the initial boundary element (initial node) is set, and the elements that are adjacent to each other from the initial boundary element (initial node) The attribute of (node) can be analyzed. Therefore, even if an object to be immersed in which another member enters inside one member is set as an analysis target, the free edge element (node) of the other member is set as an initial boundary element (initial node). Therefore, it is possible to accurately simulate the air pool generated in the object to be immersed.

  According to the method for simulating the occurrence of air accumulation in the object to be immersed according to the present invention, it is determined whether or not the direction vector extended from the free edge element (node) is visible by determining whether or not it intersects the numerical calculation model. can do. Accordingly, it is possible to determine whether or not the image is visible using the coordinate data of the free edge element (node).

  According to the method for simulating the occurrence of air accumulation in the object to be immersed according to the present invention, a normal vector extending from the free edge element is generated, and a hemispherical normal vector solid angle range through which the normal vector penetrates the top is set. A common solid angle range that is a representative point solid angle range and a normal vector solid angle range is set, and a direction vector can be extended within the common solid angle range. Therefore, it is possible to minimize the solid angle range in which the direction vector is extended and to omit useless analysis processing.

  According to the method for simulating the occurrence of air accumulation in the object to be immersed according to the present invention, the representative point height of the free edge (node height on the free edge) of the numerical calculation model in the horizontal position and the representative point height of the free edge element Compared to the height (adjacent node heights other than nodes on the free edge), and if the former is higher than or equal to the latter, the free edge element (node on the free edge) Can be set to the paint, and can also be set to the initial boundary element (initial node). Therefore, since the attribute of the initial boundary element (initial node) that should originally be air can be set to air, more accurate simulation can be performed.

  According to the invention of the method for simulating the occurrence of air stagnation in an object to be submerged according to the present invention, after the analysis processing for attribute determination of an element (node) has converged, the attribute is set as a paint and is set as an initial boundary element (initial node) Extract the free edge elements (nodes) that form the free edge of the numerical model in the horizontal position from the free edge elements (nodes), and set the attributes of the adjacent elements (nodes) of the extracted free edge elements (nodes) The attribute of the free edge element (node) can be modified accordingly. Therefore, when the attribute of the adjacent element (node) is air, the attribute of the free edge element (node) set as the initial boundary element (initial node) can be corrected to air, and simulation can be performed more accurately. it can.

  According to the method of simulating the occurrence of air accumulation in the object to be immersed according to the present invention, the object to be immersed can be a vehicle body, and in this case, a vehicle body having a complicated shape can be accurately simulated.

  According to the computer-executable program for executing the simulation method for generating air stagnation in the object to be immersed in the present invention, the computer can execute the simulation method for generating stagnation in the object to be immersed in the present invention. .

  Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a block diagram of a fluid analyzing apparatus that executes a simulation method according to the present invention.

  As shown in FIG. 1, a fluid analysis device (computer) 10 that executes a method for simulating the occurrence of air accumulation in an object to be immersed according to the present invention includes a keyboard 11 for inputting analysis conditions of the object to be immersed, an analysis process, and the like. Display 12 for displaying the results, HDD (hard disk drive) 13 for storing various data of the object to be immersed, and FDD (flexible disk drive) 14 for storing the results of analysis processing in FD (flexible disk) And have.

  The fluid analysis apparatus 10 further includes a control unit 18 including a CPU 15, ROM 16 and RAM 17, a keyboard controller 19 of the keyboard 11, a display controller 20 of the display 12, a disk controller 21 of the HDD 13 and the FDD 14, and a fluid analysis apparatus. A network interface controller 23 for connecting 10 to the network 22 is provided, and these can communicate with each other via a system bus 24.

  The CPU 15 constituting the control unit 18 executes the software stored in the ROM 16 and the HDD 13 or the software supplied from the FDD 14 so as to comprehensively control various components connected to the system bus 24. It has become. That is, the CPU 15 reads out software from the ROM 16, the HDD 13, or the FDD 14 according to a predetermined processing sequence and executes the program, thereby performing control for realizing the flowchart shown in FIG. 4.

  CPU15 reads the various data of the to-be-immersed processing object used as analysis object from HDD13, and constructs the two-dimensional numerical calculation model divided | segmented into several elements from this read-out various data. Further, the CPU 15 calculates information (data) necessary for realizing the flowchart shown in FIG. 4 based on the constructed numerical calculation model, that is, extracts the barycentric point in the element, generates the direction vector, and the like. Finally, the state of occurrence of air accumulation in the object to be immersed is displayed on the display 12.

  The RAM 17 constituting the control unit 18 functions as a main memory or work area for the CPU 15. The keyboard controller 19 controls input signals from input means such as the keyboard 11 and a pointing device (not shown), and the display controller 20 controls display on the display 12. The disk controller 21 controls access to the HDD 13 and the FDD 14 that store or read a boot program, various applications, editing files, user files, network management programs, and the like. The network interface controller 23 transmits and receives data to and from other devices (not shown) on the network 22.

  Next, an air pool generation simulation method for the object to be immersed, which is executed by the fluid analyzing apparatus 10, will be described. In the present embodiment, the analysis is performed with a box-like member provided with a partition member with a hole as shown in FIG.

  FIG. 2 is an explanatory view for explaining the object to be immersed and the coating tank, and FIG. 3 is a perspective view showing a numerical calculation model of the object to be immersed.

  As shown in FIG. 2, the object to be immersed 30 is formed in a substantially cubic shape and has a box-shaped member (one member) 31 having an opening 31 a on the lower side in the drawing, and an inner side of the box-shaped member 31. A plate-like partition member (other member) 32 that is provided and has a hole portion 32a is provided. The length dimension L1 of the partition member 32 in the vertical direction in the drawing is set to be shorter than the length dimension L2 of the box-shaped member 31 in the vertical direction in the drawing (L1 <L2). Accordingly, when the object to be treated 30 is actually immersed in the liquid paint 41 of the paint tank 40 in the posture shown in FIG. 2, the partition member 32 retains an air pool (air) of the object to be treated 30. Pocket).

  The control unit 18 (see FIG. 1) of the fluid analysis device 10 generates a plurality of two-dimensional triangular meshes (elements) 50, 50,.・ Numerical calculation model is constructed by dividing into. In constructing a two-dimensional numerical calculation model, for example, when an analysis target is a vehicle body, a numerical calculation model used in a collision deformation simulation of the vehicle body can be used. In FIG. 3, the front wall portion of the box-shaped member 31 is omitted so that the partition member 32 provided inside the box-shaped member 31 can be seen.

  As shown in the broken-line circle A part, the treatment object 30 has a plurality of nodes (nodes) 51, 51... And a plurality of triangular meshes 50, 50. And is formed by. The free edge 52 that forms the end or hole of the workpiece 30 is a plurality of free edge nodes (free edge nodes) 53, 53... And free edge mesh (free edge elements) 54, 54,.・ (Shaded area in the figure) is arranged. Here, the free edge 52 is arranged not only on the lower end of the box-shaped member 31 in the figure but also on the outer peripheral portion of the partition member 32 and the inner peripheral portion of the hole portion 32a.

  Next, the contents of the program executed by the control unit 18 of the fluid analyzing apparatus 10 will be described with reference to FIGS.

  FIG. 4 is a flowchart (main routine) showing the method for simulating the occurrence of air accumulation according to the present invention, FIGS. 5 (a) and 5 (b) are flowcharts (subroutines) showing initial condition setting processing, and FIG. 6 is a hemispherical model. 7 (a) and 7 (b) are explanatory diagrams for explaining the state of analysis processing of the flowchart of FIG. 5, and FIGS. 8 (a) and 8 (b) are processes for air pocket determination calculation. FIGS. 9A and 9B are explanatory diagrams for explaining the processing of air pocket determination calculation using a triangular mesh, and FIGS. 10A and 10B are air pocket determinations based on nodes. Explanatory drawing explaining the mode of the process of calculation is each represented.

  As shown in FIG. 4, first, when the fluid analyzing apparatus 10 is turned on and electric power is supplied to the control unit 18, initial setting of the control unit 18 is performed, and analysis processing software is transferred from the HDD 13 or the like to the RAM 17. Is read and the program for executing the method for simulating the occurrence of air accumulation in the object to be immersed according to the present invention is executed (step S1).

  Next, the operator inputs the part (P_i) to be analyzed, that is, the workpiece 30 shown in FIGS. 2 and 3 through the keyboard 11 (step S2).

  In step S3, the original data corresponding to the part (P_i) input in step S2, that is, in the case where the part (P_i) constitutes the vehicle body, the shape data (diverted) used for the vehicle body body collision deformation simulation, etc. Data) is read from the HDD 13. Then, the read shape data of the component (P_i) is divided into a plurality of two-dimensional triangular meshes, and the data generated thereby is stored in the RAM 17 to construct a numerical calculation model. Here, step S3 constitutes a first step in the present invention.

  Here, as the data of the numerical calculation model stored in the RAM 17, coordinate data including XYZ coordinate values as position information of the nodes 51, 51. , 51..., And mesh data defining three triangular meshes 50, 50.

  In step S4, the immersion direction of the object 30 to be immersed 30 in the paint tank 40, that is, the gravity direction (G) of the component (P_i) is input by operating the keyboard 11 of the operator. Then, the control unit 18 updates the coordinate data of the nodes 51, 51... Forming the triangular meshes 50, 50... Forming the part (P_i) based on the input gravity direction (G). Coordinate data (update data) in consideration of the direction of gravity (G) is stored in the RAM 17.

  In step S5, the update data stored in the RAM 17 in step S4 is used, and initial condition setting for performing analysis processing of air pocket determination calculation in subsequent step S6 is executed. In step S6, air pocket determination calculation is executed based on the numerical calculation model of the part (P_i) for which initial conditions are set in step S5.

  In step S7, the analysis result of the air pocket determination calculation in step S6 is post-processed. In subsequent step S8, the analysis result post-processed in step S7 is displayed externally via the display 12 and the analysis process is terminated. To do.

  Next, the initial condition setting analysis processing in step S5 will be described with reference to FIG. In the analysis processing after step S5A shown in FIG. 5, the initial condition setting according to the first embodiment of the present invention is executed. FIG. 5A shows the initial condition setting (first invention) using a triangular mesh. FIG. 5B shows the processing of initial condition setting by the node (eighth invention).

  As shown in FIG. 5A, in step S10, a plurality of free edge meshes (FM_i) forming the free edge (FE) of the part (P_i) are extracted and one of them is selected, that is, FIG. A plurality of free edge meshes 54 forming the free edge 52 shown in FIG. Here, step S10 constitutes a second step in the present invention.

  In step S11, the part from the opposite side to the gravity direction (G) as shown in FIGS. 6 and 7 with the representative point (for example, the center of gravity (GP)) of the free edge mesh (FM_i) selected in step S10 as the center. A hemispherical surface (S) as a hemispherical model covering (P_i) is generated. The representative point of the free edge mesh (FM_i) can be obtained by a predetermined calculation using the coordinate data of the three nodes (N) forming the free edge mesh (FM_i). However, the representative point of the free edge mesh (FM_i) is not limited to the center of gravity (GP), but may be one node (N) of the three nodes (N) forming the free edge mesh (FM_i). it can. Furthermore, any point on the free edge mesh (FM_i) obtained by the three nodes (N) forming the free edge mesh (FM_i) may be used. Here, step S11 constitutes a third step in the present invention.

  The hemispherical surface (S) generated in step S11 is formed by a plurality of two-dimensional polygonal meshes (SM_i) in the same manner as the component (P_i). The coordinate data of a plurality of nodes (SN_i) forming the hemispherical surface (S) and the mesh data of the polygon mesh (SM_i) are also stored in the RAM 17.

  The radius (R) of the hemispherical surface (S) is set to a size that can cover the component (P_i) as shown in FIG. When setting the radius (R), for example, the radius (R) is set to a value sufficiently larger than the distance between the pair of the most distant nodes (N) forming the part (P_i). Here, the radius (R) of the hemispherical surface (S) can be obtained by a predetermined calculation using the coordinate data of each node (N) forming the part (P_i).

  In step S12, data of a plurality of polygonal meshes (SM_i) of the hemispherical surface (S) stored in the RAM 17 in step S11 is extracted. In the subsequent step S13, the direction vector (V) extending from each polygon mesh (SM_i) extracted in step S12 toward the free edge mesh (FM_i) of the part (P_i) is associated with each polygon mesh (SM_i). Generation, that is, if there are n polygon meshes (SM_i) of the hemispherical surface (S), n direction vectors (V) are generated.

  As shown in FIG. 7, the direction vector (V) is generated at a representative point of the polygon mesh (SM_i) (for example, the center of gravity (GP)), and the coordinate data of the node (SN_i) forming the polygon mesh (SM_i) is obtained. Can be obtained using the outer product. The representative point of the polygon mesh (SM_i) can be obtained by a predetermined calculation using the coordinate data of the node (SN_i) forming the polygon mesh (SM_i) stored in the RAM 17 in step S11. However, the representative point of the polygon mesh (SM_i) is not limited to the centroid point (GP), but may be an arbitrary point on the polygon mesh (SM_i).

  In step S14, it is determined whether or not the free edge mesh (FM_i) forming the part (P_i) is visible when the part (P_i) is viewed from the hemispherical surface (S). Hereinafter, the specific determination method of “whether it is visible” executed in step S14 (fourth step in the present invention) will be described with reference to FIG.

  As shown in FIG. 7A, among the polygon meshes (SM_i) forming the hemispherical surface (S), for example, a direction vector (V_1) extending from the polygon mesh (SM_1) toward the free edge mesh (FM_1) think about. The direction vector (V_1) extends toward the free edge mesh (FM_1) without intersecting the other triangular mesh (M) that forms the part (P_i), and intersects the free edge mesh (FM_1) directly become. That is, the direction vector (V_1) reaches the free edge mesh (FM_1) without being obstructed by the other triangular mesh (M) that forms the part (P_i), and thus the free edge mesh from the polygon mesh (SM_1) It can be determined that (FM_1) is visible.

  Here, the intersection of the direction vector (V) and the triangular mesh (M) of the part (P_i) is obtained by using the coordinate data of the part (P_i) and the hemisphere (S) stored in the RAM 17 and using the coordinate data of the direction vector (V). It can be calculated by the linear equation and the plane equation of the triangular mesh (M) of the part (P_i).

  Thus, by calculating that the direction vector (V) does not form an intersection with another triangular mesh (M) that forms the part (P_i) in the middle, a polygonal mesh of the hemisphere (S) It can be determined that the free edge mesh (FM_i) of the part (P_i) is visible (yes) from (SM_i).

  On the other hand, as shown in FIG. 7B, for example, when a direction vector (V_2) extending from the polygon mesh (SM_2) toward the free edge mesh (FM_2) is considered, the direction vector (V_2) is represented by a component (P_i ) And other triangular meshes (M) forming the intersection (CP). Therefore, in the middle of the direction vector (V_2), another intersection (CP) is formed in addition to the intersection with the free edge mesh (FM_2). Thus, the free edge mesh (FM_2) of the part (P_i) cannot be seen from the polygonal mesh (SM_2) of the hemispherical surface (S) by calculating the intersection (CP) in the middle of the direction vector (V_2). (no) can be determined.

  Here, when determining whether or not the free edge mesh (FM_i) is visible from the polygon mesh (SM_i), whether the direction vector (V) is generated and the direction vector (V) directly intersects the free edge mesh (FM_i) Although whether or not is shown is shown, it is possible to determine “whether or not it can be seen” in step S14 by other methods.

  For example, since the polygon mesh (SM_i) and the free edge mesh (FM_i) are in a relationship that can face each other, considering the movement of radiant energy between both meshes (between both planes), the value of the shape factor F between both planes It can also be determined by calculating. In this case, the free edge mesh (FM_i) can be determined as “invisible” from the polygon mesh (SM_i) if the form factor F = 0, and free from the polygon mesh (SM_i) if the form factor F> 0. It can be determined that the edge mesh (FM_i) is “visible”.

  If it is determined (invisible) in step S14, the process returns to step S10 to determine whether or not it is visible in subsequent steps for another free edge mesh (FM_i). On the other hand, if it is determined (yes) in step S14, the process proceeds to step S15.

  In step S15, the attribute of the free edge mesh (FM_i) determined to be “visible” in step S14 is set to liquid (L) (paint), set to liquid mesh (LM_i), and the liquid mesh (LM_i) is initialized. The boundary mesh is set and the process proceeds to step S16. Here, step S15 constitutes a fifth step in the present invention.

  In step S <b> 16, it is determined whether or not the determination of “visible” is performed for all the free edge meshes (FM_i) forming the free edge (FE) of the part (P_i). If it is determined to be no in step S16, the process returns to step S10, and “whether or not it is visible” is determined in the subsequent steps for another free edge mesh (FM_i). If it is determined yes in step S16, the process proceeds to step S17, the initial condition setting analysis process is terminated, and the process proceeds to step S6 of the main routine shown in FIG.

  FIG. 5A shows a case where initial conditions are set as analysis objects in steps S10 to S16, respectively, for the free edge mesh (FM_i) of the part (P_i) and the polygonal mesh (SM_i) of the hemispherical surface (S). As in steps S10A to S16A in FIG. 5B, initial conditions can be set for the free edge node (FN_i) of the component (P_i) and the node (SN_i) of the hemispherical surface (S), respectively.

  That is, as indicated by the two-dot chain line in FIG. 7A, the direction vector (V_3) extending from the node (SN_1) forming the hemispherical surface (S) toward the free edge node (FN_1) of the component (P_i) is , Extending toward the free edge node (FN_1) without intersecting with the other triangular mesh (M) forming the part (P_i), and intersecting directly. Accordingly, the free edge node (FN_1) is determined to be “visible” in step S14A.

  On the other hand, as shown by the two-dot chain line in FIG. 7B, the direction vector (V_4) extending from the node (SN_2) toward the free edge node (FN_2) is another triangular mesh (P_i) ( Cross with M) to form an intersection (CP). Therefore, it is determined that the free edge node (FN_2) is “invisible” in step S14A.

  As described above, when the analysis process is performed using the free edge node (FN_i), the representative point of the free edge mesh (FM_i) (when compared to the analysis process using the free edge mesh (FM_i) ( There is no need to obtain the center of gravity (GP), etc., and there is an advantage that the load on the fluid analyzing apparatus 10 can be reduced.

  Next, the analysis process of the air pocket determination calculation in step S6 will be described with reference to FIGS. In the analysis processing after step S6A shown in FIG. 8, the air pocket determination calculation according to the present invention is executed. FIG. 8A shows the processing of the air pocket determination calculation (first invention) using a triangular mesh. 8 (b) shows the processing of the air pocket determination calculation by the node (eighth invention).

  As shown in FIG. 8A, in step S20, one liquid mesh (LM_i) is selected from the plurality of liquid meshes (LM_i) for which the initial condition setting has been completed in step S5 shown in FIG. In the subsequent step S21, the air mesh (AM_i) adjacent to the liquid mesh (LM_i) selected in step S20 is extracted, that is, the adjacent mesh (adjacent element) sharing the node (N) forming the liquid mesh (LM_i). Set up. Here, step S21 constitutes a sixth step in the present invention.

  In step S22, first, the center of gravity (GP) of the liquid mesh (LM_i) as the initial boundary mesh is calculated, and the center of gravity (GP) of the air mesh (AM_i) as the adjacent mesh set in step S21 is calculated. . Each barycentric point (GP) is calculated by a predetermined calculation using the coordinate data of the node (N) forming each triangular mesh (M). Then, the height of each center of gravity (GP) is compared (comparison of Z coordinate values), and the height of the center of gravity of the liquid mesh (LM_i) is equal to or higher than the height of the center of gravity of the air mesh (AM_i). If it is determined that this is the case (yes), the process proceeds to step S23.

  However, in step S22, the heights of specific nodes (N) forming the triangular mesh (M) may be compared without comparing the heights of the center of gravity points as described above. That is, the highest nodes (highest nodes) at the highest position of each triangular mesh (M) to be compared, or the lowest nodes (lowest node) at the lowest position of each triangular mesh (M). You may make it compare the length. In this way, by comparing the heights of specific nodes (N) that form each triangular mesh (M) to be compared, coordinate data can be obtained without obtaining the center of gravity (GP) of each triangular mesh (M) (Z coordinate value) can be used as it is.

  In step S23, the air mesh (AM_i) adjacent to the liquid mesh (LM_i) is changed from the liquid mesh (LM_i) forming the free edge (FE) to the liquid mesh (LM_i), as indicated by the dashed arrow in FIG. Change to LM_i), that is, change the attribute from air (A) to liquid (L).

  On the other hand, if it is determined as no in step S22, that is, if it is determined that the height of the center of gravity of the liquid mesh (LM_i) is lower than the height of the center of gravity of the air mesh (AM_i), the broken line arrow in FIG. As shown, the process proceeds to step S24 without changing the attributes of the air mesh (AM_i) adjacent to the liquid mesh (LM_i) forming the free edge (FE). Here, Step S22 and Step S24 constitute the seventh step in the present invention.

  In step S24, it is determined whether or not the analysis processing of steps S22 and S23 has been executed for all the air meshes (AM_i) extracted in step S21. If it is determined no in step S24, the analysis processing in steps S22 and S23 is executed for the other air mesh (AM_i) extracted in step S21. If it is determined as yes in step S24, that is, if it is determined (yes) that the analysis processing of steps S22 and S23 has been executed for all the air meshes (AM_i) extracted in step S21, the process proceeds to step S25.

  In step S25, first, the liquid mesh (LM_i) whose attribute has been changed in step S23 and for which analysis processing has been completed is set as a secondary boundary mesh (secondary boundary element). Then, it is determined whether analysis processing has been performed for all of the set liquid mesh (LM_i) as the secondary boundary mesh and the liquid mesh (LM_i) as the initial boundary mesh extracted in step S21.

  If NO is determined in step S25, the process returns to step S20, and the liquid mesh (LM_i) as the initial boundary mesh that has not been subjected to the analysis process and the liquid mesh (LM_i) that has been set as the secondary boundary mesh after the analysis process are completed. ) Continue the analysis process. When it determines with yes at step S25, it progresses to step S26 and the analysis process of an air pocket determination calculation is complete | finished.

  As described above, the setting of the secondary boundary mesh performed in step S25 and the analysis process using the secondary boundary mesh performed by returning to step S20 include the eighth step and the ninth step in the present invention. It is composed. In addition, the analysis process is repeatedly executed in steps S20 to S25, and when there are no adjacent meshes to be extracted one after another, the analysis process converges, and the logic for ending this analysis process is the present invention. This constitutes the tenth step.

  FIG. 8A shows a case where the air pocket determination calculation is executed using the triangular mesh (M) forming the part (P_i) in steps S20 to S25. However, in FIG. As in S25A, the air pocket determination calculation can also be executed using the node (N) forming the part (P_i).

  As described above, even when the air pocket determination calculation is performed using the node (N), as shown in FIGS. 10A and 10B, the liquid node (LN_i) as the initial node is adjacent. The air node (AN_i) as an adjacent node can be analyzed one after another as in the case of using the triangular mesh (M). Further, when the analysis process is performed using the node (N), it is not necessary to obtain the center of gravity (GP) as compared with the case where the analysis process is performed using the triangular mesh (M), and the fluid analysis apparatus 10 There is an advantage that the load on can be reduced.

  As described above in detail, according to the simulation method for generating air pools in the object to be immersed according to the first embodiment (first invention, eighth invention), the hemispherical surface (S) covering the numerical calculation model of the component (P_i) ) And the attribute of the free edge mesh (FM_i) (free edge node (FN_i)) seen when viewed from the hemisphere (S) is the liquid (L), and the free edge mesh (FM_i) ( A free edge node (FN_i)) is set as an initial boundary mesh (initial node), and attributes of meshes (nodes) adjacent to each other from the initial boundary mesh (initial node) can be analyzed.

  Therefore, even when the object to be treated 30 provided with the partition member 32 entering inside the box-shaped member 31 is an analysis target, the free edge mesh (FM_i) (free edge node (FN_i)) that forms the partition member 32 Is not set to the initial boundary mesh (initial node), and an air pool generated in the workpiece 30 can be accurately simulated.

  In addition, according to the simulation method for generating air accumulation in the object to be immersed according to the first embodiment, the direction vector extending from the hemispherical surface (S) toward the free edge mesh (FM_i) (free edge node (FN_i)). It can be determined whether or not (V) is visible by determining whether or not it directly intersects the free edge mesh (FM_i) (free edge node (FN_i)). Therefore, it can be determined whether or not it can be seen by using the coordinate data of the free edge mesh (FM_i) (free edge node (FN_i)), and it can be seen relatively easily without requiring complicated calculation. A determination of whether or not can be made.

  Next, a second embodiment of the present invention will be described with reference to FIG. 11 and FIG. FIGS. 11A and 11B are flowcharts (subroutines) showing initial condition setting processing according to the second embodiment, and FIGS. 12A and 12B are views of analysis processing of the flowchart of FIG. Each explanatory diagram to be described is shown. Note that the analysis processing other than the initial condition setting in the second embodiment is the same as that in the first embodiment described above, and a description thereof will be omitted.

  In the analysis processing after step S5B shown in FIG. 11, the initial condition setting according to the second embodiment of the present invention is executed. FIG. 11A shows the initial condition setting by the triangular mesh (third invention). FIG. 11B shows the processing of initial condition setting (tenth invention) by the nodes.

  As shown in FIG. 11A, in step S40, a plurality of free edge meshes (FM_i) forming the free edge (FE) of the part (P_i) are extracted and one of them is selected, that is, FIG. A plurality of free edge meshes 54 forming the free edge 52 shown in FIG. Here, step S40 constitutes a second step in the present invention.

  In step S41, the representative point (for example, the center of gravity (GP)) of the free edge mesh (FM_i) selected in step S40 is extracted. In subsequent step S42, a hemispherical solid angle range (representative point solid angle range) ψg is set on the side opposite to the gravity direction (G) from the gravity center point (GP) extracted in step S41. The solid angle range ψg can be obtained by a predetermined calculation using the coordinate data of the component (P_i). Here, step S41 and step S42 constitute a third step in the present invention.

  In step S43, as shown in FIG. 12, a plurality of direction vectors extending radially from the center of gravity (GP) of the free edge mesh (FM_i) in the direction of looking up within the representative point solid angle range ψg set in step S42. Generate (V).

  In step S44, it is determined whether or not there is a direction in which the direction vector (V) generated in step S43 does not intersect the other triangular mesh (M) forming the part (P_i). That is, it is determined whether there is a direction in which the part (P_i) cannot be seen from the free edge mesh (FM_i).

  If it is determined yes in step S44, that is, if it is determined that there is a direction in which the part (P_i) cannot be seen from the free edge mesh (FM_i) (invisible), the process proceeds to step S45. If it is determined as no in step S44, that is, if it is determined that there is no direction in which the part (P_i) cannot be seen from the free edge mesh (FM_i), the process returns to step S40. And after returning to step S40, the analysis process of step S41-S44 is performed by making another free edge mesh (FM_i) into object. Here, step S43 and step S44 constitute the fourth step in the present invention.

  Consider a free edge mesh (FM_1) that forms a free edge (FE) of a component (P_i) as shown in FIG. Of a plurality of direction vectors (V) extending radially in the direction of looking up within the range of the representative point solid angle range ψg, the direction vector (V_1) located on the left side in the figure is a part (P_i) on its extension There is no other triangular mesh (M) forming. Therefore, in step S44, it is determined that there is a direction that does not intersect the other triangular mesh (M) forming the part (P_i) (yes), that is, the free edge mesh (FM_1) indicates that the part (P_i) is “invisible”. Can be determined.

  On the other hand, as shown in FIG. 12 (b), when considering the free edge mesh (FM_2) that forms the free edge (FE) of the part (P_i), it radiates in the direction of looking up within the representative point solid angle range ψg. All extending direction vectors (V), that is, all direction vectors (V) including direction vectors (V_2) and (V_3) intersect with other triangular meshes (M) forming part (P_i). It will be. Therefore, in step S44, it is determined that there is no direction that does not intersect the other triangular meshes (M) forming the part (P_i) (no), that is, the free edge mesh (FM_2) indicates that the part (P_i) is “visible”. Can be determined.

  However, even in this case, since the other triangular mesh (M) that forms the part (P_i) and the free edge mesh (FM_i) can be opposed to each other, as described above, between both meshes to be compared It can be determined by obtaining the value of the form factor F. That is, if the form factor F = 0, it can be determined that the free edge mesh (FM_i) has a direction that does not intersect with other triangular meshes (M) (not visible), and the form factor F> 0. For example, it can be determined that the free edge mesh (FM_i) has no direction (visible) that does not intersect the other triangular mesh (M).

  In step S45, the attribute of the free edge mesh (FM_i) determined to be yes in step S44 is set as the liquid mesh (LM_i) as the liquid (L), and this liquid mesh (LM_i) is set as the initial boundary mesh. Proceed to step S46. Here, step S45 constitutes a fifth step in the present invention.

  In step S46, it is determined whether or not the determinations in steps S41 to S45 have been executed for all free edge meshes (FM_i) forming the free edge (FE) of the part (P_i). If it is determined no in step S46, the process returns to step S40, and the analysis processing of steps S41 to S45 is executed for another free edge mesh (FM_i). If YES is determined in step S46, the process proceeds to step S47, the initial condition setting analysis process is terminated, and the process proceeds to step S6 of the main routine shown in FIG.

  FIG. 11A shows a case where initial conditions are set using a free edge mesh (FM_i) in steps S40 to S46. However, as shown in steps S40A to S46A of FIG. The initial conditions can also be set using FN_i). That is, as indicated by a two-dot chain line in FIG. 12B, for example, a plurality of directions extending radially from the free edge node (FN_1) forming the component (P_i) in a direction looking up within the solid angle range ψg. A vector (V) is generated, and it is determined whether or not there is a direction in which the direction vector (V) does not intersect with another triangular mesh (M) forming the part (P_i).

  As described above, when the analysis process is performed using the free edge node (FN_i), the representative point of the free edge mesh (FM_i) (when compared to the analysis process using the free edge mesh (FM_i) ( There is no need to obtain the center of gravity (GP), etc., and there is an advantage that the load on the fluid analyzing apparatus 10 can be reduced.

  As described above in detail, according to the simulation method for generating air pools in the object to be immersed according to the second embodiment (third invention, tenth invention), the free edge mesh (FM_i) (free edge) of the component (P_i) When looking up from the node (FN_i) within the solid angle range ψg, it is determined whether or not the part (P_i) is visible. If it is determined that the part (P_i) is not visible, the free edge mesh (FM_i) (free Set the attribute of edge node (FN_i) to liquid (L) and set to the initial boundary mesh (initial node), and analyze the attributes of meshes (nodes) adjacent to each other from this initial boundary mesh (initial node) can do.

  Therefore, even when the object to be treated 30 provided with the partition member 32 entering inside the box-shaped member 31 is an analysis target, the free edge mesh (FM_i) (free edge node (FN_i)) that forms the partition member 32 Is not set to the initial boundary mesh (initial node), and an air pool generated in the workpiece 30 can be accurately simulated.

  In addition, according to the simulation method for generating air pools in the object to be immersed according to the second embodiment, the direction vector (V) extending from the free edge mesh (FM_i) (free edge node (FN_i)) ), It can be determined whether it is visible or not. Therefore, it can be determined whether or not it can be seen by using the coordinate data of the free edge mesh (FM_i) (free edge node (FN_i)), and it can be seen relatively easily without requiring complicated calculation. A determination of whether or not can be made.

  Next, a third embodiment of the present invention will be described with reference to FIGS. FIG. 13 is a flowchart (subroutine) showing the initial condition setting process according to the third embodiment, and FIGS. 14A and 14B are explanatory diagrams for explaining the state of the analysis process of the flowchart of FIG. ing. The third embodiment differs from the second embodiment described above in the method of setting the solid angle range, and differences from the second embodiment will be described below.

  In the analysis processing after step S5C shown in FIG. 13, initial condition setting according to the third embodiment of the present invention is executed, and instead of step S43 of initial condition setting by a triangular mesh shown in FIG. Thus, the analysis processing of steps S50 to S53 is executed (fifth invention).

  In step S50, as shown in FIG. 14A, the normal vector (NV) extended from the representative point (for example, the center of gravity (GP)) of the free edge mesh (FM_i) is converted into the left-handed coordinate system or the right-handed coordinate system. Generate according to However, when the angle θ between the normal vector (NV) and the gravity direction (G) is 90 ° or less (θ <90 °), as indicated by the broken line arrow in FIG. As shown by the solid line arrow, the normal vector (NV) is inverted to generate a new normal vector (NV ′).

  In step S51, a hemispherical solid angle range (normal vector solid angle range) ψs in which the normal vector (NV) generated in step S50 passes through the apex is obtained as indicated by a broken line arrow in FIG. .

  In step S52, as indicated by a solid arrow in FIG. 14A, the solid angle range that is the representative point solid angle range ψg set in step S42 and also the normal vector solid angle range ψs set in step S51. (Common solid angle range) ψ is obtained. Here, the setting of the common solid angle range ψ executed in steps S50 to S52 is executed in the third step of the present invention.

  In step S53, a plurality of directional vectors (V) extending radially from the center of gravity (GP) of the free edge mesh (FM_i) in the direction of looking up within the common solid angle range ψ set in step S52 are generated.

  In step S44, it is determined whether or not there is a direction in which the direction vector (V) generated in step S53 does not intersect with another triangular mesh (M) forming the part (P_i). That is, it is determined whether there is a direction in which the part (P_i) cannot be seen from the free edge mesh (FM_i). Here, Step S53 and Step S44 constitute a fourth step in the present invention.

  As described above in detail, according to the simulation method for generating air pools in the object to be immersed according to the third embodiment (the fifth invention), the normal vector (NV) extending from the free edge mesh (FM_i) is generated, A normal vector solid angle range ψs through which the normal vector (NV) penetrates the top is set, and a common solid angle range ψ that is the representative point solid angle range ψg and also the normal vector solid angle range ψs is set. The direction vector (V) can be extended within the common solid angle range ψ. Therefore, it is possible to minimize the solid angle range in which the direction vector (V) is extended and to omit useless analysis processing.

  Next, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 15 is a flowchart (subroutine) showing initial condition setting processing according to the fourth embodiment. Note that the fourth embodiment is executed by adding steps S60 and S61 shown in FIG. 15 between step S14 and step S15 in FIG. 5A as compared to the first embodiment described above (see FIG. 5A). The sixth aspect is different from the first embodiment in the following. Differences from the first embodiment will be described below.

  In the analysis processing after step S5D shown in FIG. 15, the initial condition setting according to the fourth embodiment of the present invention is executed. In step S60, the free edge mesh determined as “visible” in step S14 ( Determine whether FM_i) is in the horizontal position. Whether or not the free edge mesh (FM_i) is in the horizontal position is determined by the coordinate data (Z coordinate value) of a pair of free edge nodes (FN_i) on the free edge (FE) forming the free edge mesh (FM_i) This is done by comparing

  If it is determined as yes in step S60, that is, if it is determined that the free edge mesh (FM_i) is in the horizontal position, the process proceeds to step S61. If the determination in step S60 is no, that is, if it is determined that the free edge mesh (FM_i) is not in the horizontal position, the process proceeds to step S15. In the subsequent step S15, the attribute of the free edge mesh (FM_i) that is not in the horizontal position is set to liquid. Set to (L) to make the liquid mesh (LM_i).

  In step S61, the height of the representative point (for example, the center of gravity) of the free edge mesh (FM_i) in the horizontal position is the height of the representative point of the free edge (FE) forming the free edge mesh (FM_i), that is, Then, it is determined whether or not the height of any one of the free edge nodes (FN_i) on the free edge (FE) is higher.

  When it determines with yes in step S61, the attribute of the said free edge mesh (FM_i) is made into air (A), and it returns to step S10. When it determines with no in step S61, it progresses to step S15. Here, the analysis process executed in steps S60 to S15 is executed in the fifth step of the present invention.

  As described in detail above, according to the method for generating air accumulation in the object to be immersed according to the fourth embodiment, the height of the free edge node (FN_i) that forms the free edge (FE) in the horizontal position, Compare the representative point height of the free edge mesh (FM_i) with this free edge node (FN_i) and if the former is at a higher position or the same height as the latter, the free edge mesh (FM_i) Can be set to the liquid (L) and the initial boundary mesh.

  Therefore, since the attribute of the initial boundary mesh that should originally be air can be left as air (A), it can be more accurately simulated. In this case, since the volume of the air pool generated in the object to be immersed can be determined more accurately, for example, it is effective for determining a complete discharge time until the air completely escapes from the object to be immersed. .

  However, the analysis processing of steps S60 and S61 shown in FIG. 15 can be additionally executed between step S44 and step S45 in FIG. 11A of the second embodiment described above. The same actions and effects can also be achieved in.

  In addition, instead of the free edge mesh (FM_i) in steps S60 and S61, analysis processing can be performed using a free edge node (FN_i) forming a free edge (FE) (a twelfth invention). In this case, in step S60, it may be determined whether or not the free edge (FE) formed by the pair of free edge nodes (FN_i) is in the horizontal position. On the other hand, in step S61, the height of the free edge node (FN_i) on the free edge (FE) in the horizontal position and the nodes (N) other than on the free edge (FE) adjacent to the free edge node (FN_i) are displayed. Compare with height. In step S61, if the height of the free edge node (FN_i) is higher than or equal to the height of the adjacent node (N), the process may proceed to step S15. .

  Next, a fifth embodiment of the present invention will be described with reference to FIGS. FIG. 16 is a flowchart (main routine) showing an air pocket generation simulation method according to the fifth embodiment, FIG. 17 is a flowchart (subroutine) showing the air pocket correction process of FIG. 16, and FIG. 18 is a flowchart of FIG. An explanatory diagram for explaining the state of the analysis processing is shown. The fifth embodiment is different from the first embodiment described above in that the “air pocket correction process” is executed (step 7) between step S6 and step S7 shown in FIG. Differences from the first embodiment will be described below.

  As shown in FIG. 16, in the fifth embodiment, after completing the air pocket determination calculation in step S6 (see FIG. 8), an air pocket correction process is executed in step S70. As in the fourth embodiment, the attribute of the initial boundary mesh that should be essentially air is changed to air (A) so that simulation can be performed more accurately.

  As shown in FIG. 17, in step S71, the liquid mesh (LM_i) in the horizontal position of the part (P_i), that is, the free edge (FE) whose attribute is set to liquid (L) in the initial condition setting in step S5. A free edge mesh (FM_i) to be formed is extracted, and one liquid mesh (LM_i) is selected therefrom. The liquid mesh (LM_i) extracted in step S71 is, for example, (LM_A), (NM_1), (NM_7) in FIG. 18, and one liquid mesh (LM_A) is selected from them.

  In step S72, an adjacent mesh (NM_i) adjacent to the liquid mesh (LM_i) selected in step S71 is extracted, and the liquid mesh (LM_h) adjacent to the liquid mesh (LM_i) and the adjacent mesh (NM_i) are extracted from the adjacent mesh (NM_i). Delete (LM_j). That is, as shown in FIG. 18, adjacent meshes (NM_1) to (NM_7) of the liquid mesh (LM_A) are extracted, and the adjacent meshes (NM_1) to (NM_7) are next to the liquid mesh (LM_A). Delete the liquid meshes (NM_1) and (NM_7). Here, the liquid meshes (NM_1) and (NM_7) are deleted, but this is because they are excluded from the comparison target with the liquid mesh (LM_i) in the subsequent step S73.

  In step S73, it is determined whether there is an adjacent mesh (NM_i) whose attribute is liquid (L) among the adjacent meshes (NM_2) to (NM_6), and attributes around the liquid mesh (LM_i) are determined. Check. If it is determined as no in step S73, that is, if it is determined that there is no adjacent mesh (NM_i) whose attribute is liquid (L) in the adjacent meshes (NM_2) to (NM_6), the process proceeds to step S74. If it is determined as yes in step S73, that is, if it is determined that there is an adjacent mesh (NM_i) whose attribute is liquid (L) among the adjacent meshes (NM_2) to (NM_6), the process proceeds to step S75. In FIG. 18, since all the attributes of the adjacent meshes (NM_2) to (NM_6) are air (A), it is determined as no.

  In step S74, the liquid mesh (LM_i) is changed to an air mesh (AM_i) whose attribute is air (A), and then the process proceeds to step S78. That is, since it is determined in upstream step S73 that the attribute of the adjacent mesh (NM_i) of the liquid mesh (LM_i) is air (A), the liquid mesh (LM_i) is originally an air mesh (AM_i). Change its attribute from liquid (L) to air (A). In FIG. 18, the attribute of the liquid mesh (LM_A) to be analyzed is changed to air (A).

  In step S75, the height (for example, the height of the center of gravity) between the liquid mesh (LM_i) and the adjacent mesh (NM_i) whose attribute is liquid (L) is compared using coordinate data. In step S76, if the adjacent mesh (NM_i) of the liquid (L) is at a position higher than or at the same height as the liquid mesh (LM_i), the determination is yes and the process proceeds to step S78. When the adjacent mesh (NM_i) of the liquid (L) is at a position lower than the liquid mesh (LM_i), it is determined as no and the process proceeds to step S77.

  In step S77, the attribute of the adjacent mesh (NM_i) whose attribute is liquid (L) is changed to air (A), and the process proceeds to step S74. In step S78, it is determined whether or not the analysis processing in steps S71 to S77 has been executed for all the liquid meshes (LM_i) in the horizontal position in the component (P_i). If it is determined yes, the process proceeds to step S79. Then, the analysis process of the air pocket correction process is finished. On the other hand, if it is determined no in step S78, the process proceeds to step S71, and an analysis process of an air pocket correction process is executed for another liquid mesh (LM_i).

  As described above in detail, according to the method for simulating the occurrence of air accumulation in the object to be immersed according to the fifth embodiment, after the air pocket determination calculation is finished, the attribute is set to liquid (L) and the initial boundary mesh is set. From the set liquid mesh (LM_i), extract the liquid mesh (LM_i) that forms the free edge (FE) in the horizontal position, and according to the attribute of the adjacent mesh (NM_i) of this liquid mesh (LM_i) The attribute of the liquid mesh (LM_i) can be modified.

  Therefore, when the attribute of the adjacent mesh (NM_i) is air (A), the attribute of the liquid mesh (LM_i) set for the initial boundary mesh can be modified to air (A), and in particular, the volume of the air reservoir Can be more accurately simulated.

  However, in the analysis process of the air pocket correction process shown in FIG. 17, the triangular mesh (M) that forms the numerical calculation model of the part (P_i) is shown, but instead of this triangular mesh (M), The analysis process (13th invention) of the air pocket correction process can also be executed using the node (N) forming the numerical calculation model of the part (P_i). Even in this case, the same actions and effects can be achieved.

  In addition, this invention is not limited to each embodiment mentioned above, A various change is possible in the range which does not deviate from the summary. For example, in each of the above-described embodiments, the flow and shaking of the paint that changes due to the viscosity characteristics of the paint, the change in the immersion direction of the object to be immersed (change in the hanging posture), etc. are analyzed without correction calculation. Although what performed a process was shown, this invention is not restricted to this, You may make it perform correction | amendment calculation in consideration of the viscosity conditions of a coating material, the change conditions of an immersion direction, etc. FIG. In this case, it is possible to accurately determine the volume of the air pool generated in the object to be immersed, and to estimate the complete discharge time of air discharged from the object to be immersed.

  Further, in each of the above embodiments, it has been described that the object to be immersed can be applied to the vehicle body. However, the present invention is not limited to this. For example, the vehicle body frame of a railway vehicle, the cabin of a construction machine, and the like are covered. It can also be a target of the immersion treatment.

It is a block diagram of the fluid analysis apparatus which performs the simulation method concerning the present invention. It is explanatory drawing explaining a to-be-immersed processed material and a coating tank. It is a perspective view which shows the numerical calculation model of a to-be-immersed process thing. It is a flowchart (main routine) which shows the air pocket generation | occurrence | production simulation method which concerns on this invention. (A), (b) is a flowchart (subroutine) which shows the process of initial condition setting. It is explanatory drawing explaining a hemispherical model. (A), (b) is explanatory drawing explaining the mode of the analysis process of the flowchart of FIG. (A), (b) is a flowchart (subroutine) which shows the process of air pocket determination calculation. (A), (b) is explanatory drawing explaining the mode of the process of the air pocket determination calculation by a triangular mesh. (A), (b) is explanatory drawing explaining the mode of the process of the air pocket determination calculation by a node. (A), (b) is a flowchart (subroutine) which shows the process of the initial condition setting which concerns on 2nd Embodiment. (A), (b) is explanatory drawing explaining the mode of the analysis process of the flowchart of FIG. It is a flowchart (subroutine) which shows the process of the initial condition setting which concerns on 3rd Embodiment. (A), (b) is explanatory drawing explaining the mode of the analysis process of the flowchart of FIG. It is a flowchart (subroutine) which shows the process of the initial condition setting which concerns on 4th Embodiment. It is a flowchart (main routine) which shows the air pocket generation | occurrence | production simulation method which concerns on 5th Embodiment. It is a flowchart (subroutine) which shows the air pocket correction process of FIG. It is explanatory drawing explaining the mode of the analysis process of the flowchart of FIG.

Explanation of symbols

10 Fluid analyzer (computer)
18 Control part 30 Substrate to be processed 31 Box-shaped member (Subject to be processed)
32 Partition member (substance to be immersed)
40 Paint tank 41 Liquid paint (paint)
50 Triangular mesh (two-dimensional element)
51 nodes (nodes)
52 Free edge 53 Free edge node (Free edge node)
54 Free edge mesh (free edge element)
ψg representative point solid angle range ψs normal vector solid angle range ψ common solid angle range

Claims (28)

It is an air pool generation simulation method in an object to be immersed for simulating an air pool generated in an object to be immersed when immersed in a paint tank,
A first step of constructing a numerical calculation model by dividing the shape data of the object to be immersed into a plurality of two-dimensional elements;
A second step of extracting free edge elements that form ends or holes of the numerical model;
A third step of generating a hemispherical model covering the numerical calculation model from the opposite side of the direction of gravity of the numerical calculation model;
A fourth step of determining whether the free edge element is visible when viewing the numerical calculation model from the hemispherical model;
After determining that the free edge element is visible in the fourth step, a fifth step of setting the attribute of the free edge element to paint and setting the free edge element to an initial boundary element;
A sixth step of setting an element sharing a node with the initial boundary element as an adjacent element;
Analyzing the adjacent element set in the sixth step using the initial boundary element, and setting the attribute of the adjacent element based on the analysis result;
An eighth step of setting the adjacent element that has been analyzed in the seventh step as a secondary boundary element, and setting an element that shares a node with the secondary boundary element as an adjacent element;
Analyzing the adjacent element set in the eighth step using the secondary boundary element, and setting the attribute of the adjacent element based on the analysis result;
It is determined whether there is an adjacent element adjacent to the secondary boundary element, and if it is determined that there is an adjacent element adjacent to the secondary boundary element, there is no adjacent element adjacent to the secondary boundary element. Up to the eighth step and the ninth step until the process of each step is repeated, and when it is determined that there is no adjacent element adjacent to the secondary boundary element, the analysis is terminated. A method for simulating the occurrence of air accumulation in an object to be dipped, comprising:   2. The method of simulating the occurrence of air accumulation in an object to be immersed according to claim 1, wherein in the fourth step, a direction vector extending from the hemispherical model toward the free edge element is generated, and the free edge element It is determined whether or not it intersects directly with the free edge element, and when it is determined that it intersects directly with the free edge element, the free edge element can be seen. It is an air pool generation simulation method in an object to be immersed for simulating an air pool generated in an object to be immersed when immersed in a paint tank,
A first step of constructing a numerical calculation model by dividing the shape data of the object to be immersed into a plurality of two-dimensional elements;
A second step of extracting free edge elements that form ends or holes of the numerical model;
A third step of setting a hemispherical representative point solid angle range on the side opposite to the direction of gravity of the numerical calculation model at the representative point of the free edge element;
A fourth step of determining whether or not the numerical calculation model is visible when looking up from the representative point of the free edge element within the solid angle range of the representative point;
After determining that the numerical calculation model is not visible in the fourth step, a fifth step of setting the attribute of the free edge element to paint and setting the free edge element to an initial boundary element;
A sixth step of setting an element sharing a node with the initial boundary element as an adjacent element;
Analyzing the adjacent element set in the sixth step using the initial boundary element, and setting the attribute of the adjacent element based on the analysis result;
An eighth step of setting the adjacent element that has been analyzed in the seventh step as a secondary boundary element, and setting an element that shares a node with the secondary boundary element as an adjacent element;
Analyzing the adjacent element set in the eighth step using the secondary boundary element, and setting the attribute of the adjacent element based on the analysis result;
It is determined whether there is an adjacent element adjacent to the secondary boundary element, and if it is determined that there is an adjacent element adjacent to the secondary boundary element, there is no adjacent element adjacent to the secondary boundary element. Up to the eighth step and the ninth step until the process of each step is repeated, and when it is determined that there is no adjacent element adjacent to the secondary boundary element, the analysis is terminated. A method for simulating the occurrence of air accumulation in an object to be dipped, comprising:   4. The method for simulating the occurrence of air accumulation in an object to be immersed according to claim 3, wherein, in the fourth step, a direction vector extending from a representative point of the free edge element is generated and intersects with the numerical calculation model. The method for simulating the occurrence of air stagnation in an object to be immersed is characterized in that, when it is determined whether or not it intersects with the numerical calculation model, the numerical calculation model is visible.   5. The method of simulating the occurrence of air accumulation in an object to be immersed according to claim 3 or 4, wherein in the third step, a normal vector extending from a representative point of the free edge element is further generated; Performing a step of setting a hemispherical normal vector solid angle range through which the vector penetrates the top, and a step of setting a common solid angle range which is the representative point solid angle range and the normal vector solid angle range; In the fourth step, the determination is made based on the common solid angle range instead of the representative point solid angle range.   In the simulation method of the air clogging generation in the object to be immersed according to any one of claims 1 to 5, in the fifth step, a representative point height of a free edge of the numerical calculation model in a horizontal position, The free edge element is compared with the representative point height, and the free edge representative point height is higher than or equal to the representative point height of the free edge element. A method for simulating the occurrence of air stagnation in an object to be immersed, characterized in that the attribute of the element is set to paint and the free edge element is set as an initial boundary element.   The method for simulating the occurrence of air accumulation in an object to be immersed according to claim 1, wherein, in addition to the tenth step, a free of the numerical calculation model in a horizontal position from among the free edge elements. The method includes an eleventh step of extracting the free edge element forming an edge and modifying the attribute of the free edge element in accordance with the attribute of the adjacent element in the extracted free edge element. A method for simulating the occurrence of air accumulation in a processed product It is an air pool generation simulation method in an object to be immersed for simulating an air pool generated in an object to be immersed when immersed in a paint tank,
A first step of constructing a numerical calculation model by arranging a plurality of nodes on the surface of the shape data of the object to be immersed;
A second step of extracting free edge nodes forming an end or hole of the numerical calculation model;
A third step of generating a hemispherical model covering the numerical calculation model from the opposite side of the direction of gravity of the numerical calculation model;
A fourth step of determining whether the free edge node is visible when viewing the numerical calculation model from the hemispherical model;
After determining that the free edge node is visible in the fourth step, a fifth step of setting the attribute of the free edge node to paint and setting the free edge node as an initial node;
A sixth step of setting a node adjacent to the initial node as an adjacent node;
Analyzing the adjacent node set in the sixth step using the initial node, and setting the attribute of the adjacent node based on the analysis result;
An eighth step of setting the adjacent node analyzed in the seventh step as a secondary node and setting a node adjacent to the secondary node as an adjacent node;
Analyzing the adjacent node set in the eighth step using the secondary node, and setting the attribute of the adjacent node based on the analysis result;
It is determined whether there is an adjacent node adjacent to the secondary node, and when it is determined that there is an adjacent node adjacent to the secondary node, until there is no adjacent node adjacent to the secondary node, A tenth step of repeating the process of each step in the order of the eighth step and the ninth step, and ending the analysis when it is determined that there is no adjacent node adjacent to the secondary node. A method for simulating the occurrence of air accumulation in a featured object to be immersed   9. The method of simulating the occurrence of air accumulation in an object to be immersed according to claim 8, wherein in the fourth step, a direction vector extending from the hemispherical model toward the free edge node is generated, and the free edge node is generated. It is determined whether or not it intersects directly with the free edge node, and the free edge node is visible when it is determined that the free edge node is directly intersected. It is an air pool generation simulation method in an object to be immersed for simulating an air pool generated in an object to be immersed when immersed in a paint tank,
A first step of constructing a numerical calculation model by arranging a plurality of nodes on the surface of the shape data of the object to be immersed;
A second step of extracting free edge nodes forming an end or hole of the numerical calculation model;
A third step of setting a hemispherical solid angle range from the free edge node to the opposite side of the direction of gravity of the numerical calculation model;
A fourth step of determining whether the numerical calculation model is visible when looking up in the solid angle range from the free edge node;
After determining that the numerical calculation model is not visible in the fourth step, a fifth step of setting the attribute of the free edge node to paint and setting the free edge node to an initial node;
A sixth step of setting a node adjacent to the initial node as an adjacent node;
Analyzing the adjacent node set in the sixth step using the initial node, and setting the attribute of the adjacent node based on the analysis result;
An eighth step of setting the adjacent node analyzed in the seventh step as a secondary node and setting a node adjacent to the secondary node as an adjacent node;
Analyzing the adjacent node set in the eighth step using the secondary node, and setting the attribute of the adjacent node based on the analysis result;
It is determined whether there is an adjacent node adjacent to the secondary node, and when it is determined that there is an adjacent node adjacent to the secondary node, until there is no adjacent node adjacent to the secondary node, A tenth step of repeating the process of each step in the order of the eighth step and the ninth step, and ending the analysis when it is determined that there is no adjacent node adjacent to the secondary node. A method for simulating the occurrence of air accumulation in a featured object to be immersed   The method for simulating the occurrence of air accumulation in an object to be immersed according to claim 10, wherein in the fourth step, a direction vector extending from the free edge node is generated and whether or not the numerical calculation model is intersected. A method for simulating the occurrence of air accumulation in an object to be submerged, wherein the numerical calculation model is visible when it is determined and determined not to intersect the numerical calculation model.   In the simulation method of the air clogging generation in the to-be-immersed treatment object according to any one of claims 8 to 11, in the fifth step, the height of the node on the free edge of the numerical calculation model in the horizontal position, The height of the node other than on the free edge adjacent to the node is compared, and the height of the node on the free edge is higher than or equal to the height of the node other than on the free edge. If this is the case, the method of simulating the occurrence of air accumulation in the object to be immersed is characterized in that the attribute of the node on the free edge is set to paint and the node on the free edge is set as an initial boundary element.   In the simulation method of the air clogging generation in the to-be-immersed treatment object according to any one of claims 8 to 11, in addition to the tenth step, a free of the numerical calculation model in a horizontal position from the free edge nodes. The method includes an eleventh step of extracting the free edge node forming an edge and correcting the attribute of the free edge node according to the attribute of the adjacent node of the extracted free edge node. A method for simulating the occurrence of air accumulation in a processed product   14. The method for simulating the occurrence of air accumulation in an object to be immersed according to claim 1, wherein the object to be immersed is a vehicle body. Method. A computer-executable program for executing an air pool generation simulation method in an object to be immersed for simulating an air pool generated in an object to be immersed at the time of immersion in a paint tank,
A first step of constructing a numerical calculation model by dividing the shape data of the object to be immersed into a plurality of two-dimensional elements;
A second step of extracting free edge elements that form ends or holes of the numerical model;
A third step of generating a hemispherical model covering the numerical calculation model from the opposite side of the direction of gravity of the numerical calculation model;
A fourth step of determining whether the free edge element is visible when viewing the numerical calculation model from the hemispherical model;
After determining that the free edge element is visible in the fourth step, a fifth step of setting the attribute of the free edge element to paint and setting the free edge element to an initial boundary element;
A sixth step of setting an element sharing a node with the initial boundary element as an adjacent element;
Analyzing the adjacent element set in the sixth step using the initial boundary element, and setting the attribute of the adjacent element based on the analysis result;
An eighth step of setting the adjacent element that has been analyzed in the seventh step as a secondary boundary element, and setting an element that shares a node with the secondary boundary element as an adjacent element;
Analyzing the adjacent element set in the eighth step using the secondary boundary element, and setting the attribute of the adjacent element based on the analysis result;
It is determined whether there is an adjacent element adjacent to the secondary boundary element, and if it is determined that there is an adjacent element adjacent to the secondary boundary element, there is no adjacent element adjacent to the secondary boundary element. Up to the eighth step and the ninth step until the process of each step is repeated, and when it is determined that there is no adjacent element adjacent to the secondary boundary element, the analysis is terminated. A computer-executable program for executing a method for simulating the occurrence of air stagnation in an object to be immersed.   16. The computer-executable program for executing the method for simulating the occurrence of air accumulation in an object to be immersed according to claim 15, wherein in the fourth step, a direction vector is extended from the hemispherical model toward the free edge element. And determining whether or not to directly intersect with the free edge element, and when it is determined to directly intersect with the free edge element, the free edge element is visible. A computer-executable program for executing the method for simulating the occurrence of air accumulation in the computer. A computer-executable program for executing an air pool generation simulation method in an object to be immersed for simulating an air pool generated in an object to be immersed at the time of immersion in a paint tank,
A first step of constructing a numerical calculation model by dividing the shape data of the object to be immersed into a plurality of two-dimensional elements;
A second step of extracting free edge elements that form ends or holes of the numerical model;
A third step of setting a hemispherical representative point solid angle range on the side opposite to the direction of gravity of the numerical calculation model at the representative point of the free edge element;
A fourth step of determining whether or not the numerical calculation model is visible when looking up from the representative point of the free edge element within the solid angle range of the representative point;
After determining that the numerical calculation model is not visible in the fourth step, a fifth step of setting the attribute of the free edge element to paint and setting the free edge element to an initial boundary element;
A sixth step of setting an element sharing a node with the initial boundary element as an adjacent element;
Analyzing the adjacent element set in the sixth step using the initial boundary element, and setting the attribute of the adjacent element based on the analysis result;
An eighth step of setting the adjacent element that has been analyzed in the seventh step as a secondary boundary element, and setting an element that shares a node with the secondary boundary element as an adjacent element;
Analyzing the adjacent element set in the eighth step using the secondary boundary element, and setting the attribute of the adjacent element based on the analysis result;
It is determined whether there is an adjacent element adjacent to the secondary boundary element, and if it is determined that there is an adjacent element adjacent to the secondary boundary element, there is no adjacent element adjacent to the secondary boundary element. Up to the eighth step and the ninth step until the process of each step is repeated, and when it is determined that there is no adjacent element adjacent to the secondary boundary element, the analysis is terminated. A computer-executable program for executing a method for simulating the occurrence of air stagnation in an object to be immersed.   The computer-executable program for executing the method for simulating the occurrence of air stagnation in a workpiece to be immersed according to claim 17, wherein in the fourth step, a direction vector extending from a representative point of the free edge element is generated. Determining whether or not the numerical calculation model intersects, and determining that the numerical calculation model does not intersect with the numerical calculation model, the numerical calculation model is visible. A computer executable program that performs the method.   The computer-executable program for executing the method for simulating the occurrence of air accumulation in the object to be immersed according to claim 17 or 18, wherein the third step further includes a normal vector extending from a representative point of the free edge element. Generating a hemispherical normal vector solid angle range through which the normal vector penetrates the top, and a common solid angle range that is the representative point solid angle range and the normal vector solid angle range And in the fourth step, determination based on the common solid angle range instead of the representative point solid angle range is performed. A program that can be executed by a computer.   The computer-executable program for executing the simulation method for generating air stagnation in an object to be immersed according to any one of claims 15 to 19, wherein in the fifth step, the numerical calculation model in a horizontal position is The representative point height of the free edge is compared with the representative point height of the free edge element, and the representative point height of the free edge is higher than or equal to the representative point height of the free edge element. If this is the case, the computer for executing the method for simulating the accumulation of air in the object to be immersed is characterized in that the attribute of the free edge element is set to paint and the free edge element is set to an initial boundary element. An executable program.   The computer-executable program for executing the method of simulating the occurrence of air stagnation in the object to be immersed according to any one of claims 15 to 19, wherein in addition to the tenth step, a horizontal line is selected from the free edge elements. An eleventh step of extracting the free edge element forming the free edge of the numerical calculation model at a position and correcting the attribute of the free edge element according to the attribute of the adjacent element in the extracted free edge element A computer-executable program for executing a method for simulating the occurrence of air stagnation in an object to be immersed. A computer-executable program for executing an air pool generation simulation method in an object to be immersed for simulating an air pool generated in an object to be immersed at the time of immersion in a paint tank,
A first step of constructing a numerical calculation model by arranging a plurality of nodes on the surface of the shape data of the object to be immersed;
A second step of extracting free edge nodes forming an end or hole of the numerical calculation model;
A third step of generating a hemispherical model covering the numerical calculation model from the opposite side of the direction of gravity of the numerical calculation model;
A fourth step of determining whether the free edge node is visible when viewing the numerical calculation model from the hemispherical model;
After determining that the free edge node is visible in the fourth step, a fifth step of setting the attribute of the free edge node to paint and setting the free edge node as an initial node;
A sixth step of setting a node adjacent to the initial node as an adjacent node;
Analyzing the adjacent node set in the sixth step using the initial node, and setting the attribute of the adjacent node based on the analysis result;
An eighth step of setting the adjacent node analyzed in the seventh step as a secondary node and setting a node adjacent to the secondary node as an adjacent node;
Analyzing the adjacent node set in the eighth step using the secondary node, and setting the attribute of the adjacent node based on the analysis result;
It is determined whether there is an adjacent node adjacent to the secondary node, and when it is determined that there is an adjacent node adjacent to the secondary node, until there is no adjacent node adjacent to the secondary node, A tenth step of repeating the process of each step in the order of the eighth step and the ninth step, and ending the analysis when it is determined that there is no adjacent node adjacent to the secondary node. A computer-executable program for executing a method for simulating the occurrence of air accumulation in a feature to be immersed.   23. The computer-executable program for executing the method for simulating the occurrence of air accumulation in an object to be immersed according to claim 22, wherein in the fourth step, a direction vector extending from the hemispherical model toward the free edge node. And determining whether or not to directly intersect with the free edge node, and when it is determined to directly intersect with the free edge node, the free edge node can be seen. A computer-executable program for executing the method for simulating the occurrence of air accumulation in the computer. A computer-executable program for executing an air pool generation simulation method in an object to be immersed for simulating an air pool generated in an object to be immersed at the time of immersion in a paint tank,
A first step of constructing a numerical calculation model by arranging a plurality of nodes on the surface of the shape data of the object to be immersed;
A second step of extracting free edge nodes forming an end or hole of the numerical calculation model;
A third step of setting a hemispherical solid angle range from the free edge node to the opposite side of the direction of gravity of the numerical calculation model;
A fourth step of determining whether the numerical calculation model is visible when looking up in the solid angle range from the free edge node;
After determining that the numerical calculation model is not visible in the fourth step, a fifth step of setting the attribute of the free edge node to paint and setting the free edge node to an initial node;
A sixth step of setting a node adjacent to the initial node as an adjacent node;
Analyzing the adjacent node set in the sixth step using the initial node, and setting the attribute of the adjacent node based on the analysis result;
An eighth step of setting the adjacent node analyzed in the seventh step as a secondary node and setting a node adjacent to the secondary node as an adjacent node;
Analyzing the adjacent node set in the eighth step using the secondary node, and setting the attribute of the adjacent node based on the analysis result;
It is determined whether there is an adjacent node adjacent to the secondary node, and when it is determined that there is an adjacent node adjacent to the secondary node, until there is no adjacent node adjacent to the secondary node, A tenth step of repeating the process of each step in the order of the eighth step and the ninth step, and ending the analysis when it is determined that there is no adjacent node adjacent to the secondary node. A computer-executable program for executing a method for simulating the occurrence of air accumulation in a feature to be immersed.   25. In a computer-executable program for executing a simulation method for generating air stagnation in an object to be immersed according to claim 24, in the fourth step, a direction vector extending from the free edge node is generated, and the numerical value is set. Determine whether or not to intersect with the calculation model, and execute the air pool generation simulation method in the object to be immersed, characterized in that the numerical calculation model is visible when it is determined that it does not intersect with the numerical calculation model A computer executable program.   The computer-executable program for executing the simulation method for generating air stagnation in the object to be immersed according to any one of claims 22 to 25, wherein in the fifth step, the numerical calculation model in the horizontal position is Compare the height of the node on the free edge with the height of the node on the free edge that is not on the free edge, and the height of the node on the free edge is higher than the height of the node on the free edge. When the height is the same or the same height, the attribute of the node on the free edge is set in the paint, and the node on the free edge is set as an initial boundary element. A computer-executable program for executing a method for simulating the occurrence of air accumulation in a processed product.   The computer-executable program for executing the method for simulating the occurrence of air stagnation in the object to be immersed according to any one of claims 22 to 25, wherein in addition to the tenth step, a horizontal line is selected from the free edge nodes. An eleventh step of extracting the free edge node forming the free edge of the numerical calculation model at the position and correcting the attribute of the free edge node according to the attribute of the adjacent node of the extracted free edge node A computer-executable program for executing a method for simulating the occurrence of air stagnation in an object to be immersed.   The computer-executable program for executing the simulation method for generating air stagnation in the object to be immersed according to any one of claims 15 to 27, wherein the object to be immersed is a vehicle body. A computer-executable program for executing a method for simulating the occurrence of air accumulation in an object to be immersed.

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