JP5583505B2 - Simulation method and simulation program - Google Patents

Description

  The present invention relates to a simulation technique for predicting an air pool when a work is submerged in a processing tank or a liquid pool when the work is pulled up from the processing tank.

  As a method of painting or plating a workpiece, there is a dip method in which the workpiece is submerged in a treatment tank in which a treatment liquid is stored. In such a dip method, in order to satisfactorily form a paint film or a metal film, a work shape that does not cause air accumulation is required. Moreover, in order to avoid the coating defect etc. in a post process, the workpiece | work shape which does not generate | occur | produce a liquid pool when raising a workpiece | work from a processing tank is calculated | required. In view of this, a simulation method for predicting an air pool or a liquid pool at the design stage has been proposed in order to efficiently design a workpiece shape that does not generate an air pool or a liquid pool (see, for example, Patent Document 1).

JP 2008-77347 A

  By the way, when a car body of an automobile is used as a workpiece, a plurality of panels are joined by welding or the like. Therefore, in order to accurately predict an air pool or a liquid pool, an analysis model reflecting individual panel shapes is used. It was necessary to prepare an analysis model reflecting the joints between the panels. However, since the vehicle body is composed of a large number of panels, preparing an analysis model that reflects the joint location has been a factor that increases work costs.

  In addition, it is assumed that the processing liquid and the air are blocked by the dimensions of the panel interval even at a position where the panels are not joined by welding or the like, that is, a position where the processing liquid or air can move. In other words, in order to improve the prediction accuracy of the air pool and the liquid pool, there are many places that should be reflected in the analysis model even if they are not the joint places. Preparation of an analysis model reflecting these points has been a factor that further increases work costs.

  An object of the present invention is to improve the prediction accuracy of an air pool or a liquid pool while suppressing the operation cost.

The simulation method of the present invention is executed by a simulation apparatus, and when a work constituted by a plurality of panel members is submerged in a treatment tank in which a treatment liquid is accumulated, or when the work is lifted from the treatment tank. A simulation method for predicting a liquid pool of a panel, wherein an analysis model of each panel member composed of a plurality of elements is used, and whether there is an element of another analysis model within a predetermined distance from the element of one analysis model A distance determination step for determining whether or not the elements existing within the predetermined distance are connected, a model integration step for integrating the one analysis model and the other analysis model, and an integrated analysis model for each element, have a, a gas-liquid determination step of determining whether in contact with any of the processing solution with air, the predetermined distance, the processing solution Others characterized in that it is set on the basis of the viscosity of air.

  In the simulation method of the present invention, the elements constituting the analysis model are a plurality of surface elements that divide the surface shape of the panel member, or a plurality of node elements provided at the vertices of the surface elements. .

The simulation program of the present invention is executed by a simulation apparatus, and when a work constituted by a plurality of panel members is submerged in a treatment tank in which a treatment liquid is accumulated, or when the work is lifted from the treatment tank This is a simulation program for predicting the liquid pool of a panel, and whether or not there is an element of another analysis model within a predetermined distance from the element of one analysis model using the analysis model of each panel member composed of a plurality of elements A distance determination step for determining whether or not the elements existing within the predetermined distance are connected, a model integration step for integrating the one analysis model and the other analysis model, and an integrated analysis model for each element, possess the treatment liquid and the gas-liquid determination step of determining whether in contact with any of the air, the said predetermined distance It is characterized in that it is set based on the viscosity of the treatment liquid or air.

  In the simulation program of the present invention, the elements constituting the analysis model are a plurality of surface elements that divide the surface shape of the panel member, or a plurality of node elements provided at the vertices of the surface elements. .

  According to the present invention, since the elements existing within a predetermined distance are connected to each other and the analysis model for each panel member is integrated, the analysis model can be constructed with the gap between the panel members closed. Thereby, it is possible to predict an air pool or a liquid pool under a state in which a gap in which the processing liquid or air does not easily pass is closed, and it is possible to improve the prediction accuracy. In addition, since it is determined based on the distance whether or not the elements are connected to each other, the analysis model can be easily integrated, and the operation cost can be suppressed.

It is the schematic which shows an electrodeposition coating process. It is a block diagram which shows a simulation apparatus. It is explanatory drawing which shows the structure of a vehicle body. It is explanatory drawing which shows the data of the analysis model stored in a memory | storage device. (a)-(c) is explanatory drawing which shows two simplified panel analysis models. (a)-(d) is explanatory drawing which shows the procedure at the time of integrating a panel analysis model. It is a flowchart which shows the procedure at the time of integrating a panel analysis model. It is a flowchart which shows the execution procedure of the gas-liquid determination process which estimates an air pocket. It is explanatory drawing which shows the condition when a gas-liquid determination process is performed about the integrated analysis model. (a)-(c) is explanatory drawing which shows the condition when a gas-liquid determination process is performed about the unintegrated panel analysis model. (a) is explanatory drawing which shows the panel analysis model before integration, (b) is explanatory drawing which shows the analysis model after integration. It is a flowchart which shows the execution procedure of the gas-liquid determination process which estimates a liquid pool. It is explanatory drawing which shows the condition when a gas-liquid determination process is performed about the integrated analysis model. (a)-(c) is explanatory drawing which shows the condition when a gas-liquid determination process is performed about the unintegrated panel analysis model.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic view showing an electrodeposition coating process. As shown in FIG. 1, in order to perform electrodeposition coating on a vehicle body 10 that is a workpiece, a treatment tank 11 in which an electrodeposition liquid (treatment liquid) is stored is installed in the electrodeposition coating process. After subjecting the vehicle body 10 to pretreatment such as degreasing and surface adjustment, the vehicle body 10 is energized while being submerged in the treatment tank 11, so that the outer surface and the inner surface of the vehicle body 10 are electrodeposited. A coating film is formed. Thereafter, the vehicle body 10 pulled up from the treatment tank 11 is transported to a baking process for curing the electrodeposition coating film after excess paint or the like is removed in the water washing process. In order to obtain good coating quality in such an electrodeposition coating process, there is a need for a vehicle body shape that does not cause air accumulation when the vehicle body 10 is submerged in the treatment tank 11. Further, in order to avoid coating defects such as sagging in the post-process, a vehicle body shape that does not cause a liquid pool when the vehicle body 10 is pulled up from the treatment tank 11 is required. In order to efficiently design such a vehicle body shape, it is important to predict the occurrence of air pools and liquid pools with high accuracy at the design stage.

  Hereinafter, a simulation method and a simulation program according to an embodiment of the present invention will be described. Here, FIG. 2 is a block diagram showing the simulation device 12, and a simulation method and a simulation program are executed by the simulation device 12. As shown in FIG. 2, the simulation apparatus 12 includes a calculation device 13 configured by a CPU, a memory, and the like, an input device 14 such as a keyboard, a display device 15 such as a liquid crystal display, and a storage device 16 such as a magnetic disk. . The simulation apparatus 12 may be configured using a single computer such as a microcomputer or a personal computer, or may be configured using a plurality of computers connected to each other via a network.

  An analysis model of each panel member constituting the vehicle body 10 is stored in the storage device 16 constituting the simulation device 12. Here, FIG. 3 is an explanatory view showing the structure of the vehicle body 10, and FIG. 4 is an explanatory view showing data of an analysis model stored in the storage device 16. As shown in FIG. 3, the vehicle body 10 includes large parts such as an underbody 20, a side body 21, a front body 22, and a rear body 23. Furthermore, large parts such as the underbody 20 are configured by joining a plurality of panel members. For example, panel members constituting the underbody 20 include panel members such as a front floor 24, a center floor 25, and a rear floor 26. Thus, the vehicle body 10 is constituted by a plurality of panel members, and an analysis model (hereinafter referred to as a panel analysis model) is constructed for each of these panel members. As shown in the enlarged portion of FIG. 3, the panel analysis model is composed of a plurality of surface elements that divide the surface shape of the panel member, and node elements (hereinafter referred to as nodes) provided at the vertices of the surface elements. . Such a panel analysis model is stored in the storage device 16 in the form of coordinate data or the like where each node is located. As shown in FIG. 4, the storage device 16 includes panel member number data (1 to N) corresponding to each panel analysis model, node number data (1 to n) included in each panel analysis model, and each node. Coordinate data (X coordinate value, Y coordinate value, Z coordinate value) is stored. Note that the direction of the Z axis in the XYZ orthogonal coordinate system is set to be opposite to the gravity direction G. As the panel analysis model, an analysis model used for a collision deformation simulation or the like can be used.

  The arithmetic unit 13 also includes a model construction unit 30. The model construction unit 30 integrates the panel analysis models to construct one analysis model that represents the entire vehicle body (hereinafter referred to as a vehicle body analysis model). Here, FIGS. 5A to 5C are explanatory views showing two simplified panel analysis models. FIGS. 6A to 6D are explanatory diagrams showing a procedure for integrating panel analysis models. FIG. 6 shows a panel analysis model viewed from the direction of arrow A in FIG. As shown in FIGS. 5A and 5B, a panel analysis model I is provided as one analysis model, and a panel analysis model J is provided as another analysis model. These panel analysis models I and J include a plurality of nodes i1 to i15 and j1 to j15. Further, as shown in FIG. 5C, the two panel analysis models I and J are designed to be close to each other. By performing integration processing on these panel analysis models I and J, the panel analysis models I and J are integrated into one analysis model. Hereinafter, the process of integrating the panel analysis models I and J will be described using the nodes i1 to i5 and j1 to j5 provided at one end of the panel analysis models I and J as examples.

  As shown in FIG. 6A, a reference node i1 serving as a reference is set from the nodes i1 to i5 included in the panel analysis model I. Subsequently, target nodes j2 to j4 close to the reference node i1 are searched from the nodes j1 to j5 included in the panel analysis model J. Next, as shown in FIG. 6B, the node distances D12 to D14 between the reference node i1 and the target nodes j2 to j4 are calculated, and it is determined whether or not the node distances D12 to D14 are equal to or less than a predetermined distance α. . As shown in FIG. 6C, the nodes i1 and j3 whose node distance is equal to or less than the predetermined distance α are set as adjacent nodes connected to each other on the analysis model. Such an integration process of the panel analysis model is executed for all the nodes i1 to i5 of the panel analysis model I while updating the reference nodes. As a result, as shown in FIG. 6D, the panel analysis model I and the panel analysis model J are integrated into one analysis model K via the nodes i1 to i3 and j1 to j3 which are adjacent nodes. By executing such integration processing for all the panel analysis models (1 to N), one vehicle body analysis model representing the entire vehicle body is constructed. In addition, the adjacent node means a node adjacent through one side of the surface element. In the case shown in the figure, the integration processing is executed for two panel analysis models. However, when other panel analysis models are close to each other, the integration processing is performed for three or more panel analysis models at the same time. May be executed.

Here, the predetermined distance α, which is a criterion for setting adjacent nodes, is a distance set based on the viscosity of air or electrodeposition liquid. When building a vehicle body analysis model for predicting air accumulation, it is necessary to close the gap between panel members that cannot sufficiently pass air, so the predetermined distance α is set based on the viscosity of the air. Yes. That is, in a portion where the interval between the panel members is narrow (a portion where the distance is equal to or less than the predetermined distance α), it is difficult for air to escape when the vehicle body 10 is actually submerged in the treatment tank 11. I try to handle it. On the other hand, when constructing a vehicle body analysis model for predicting a liquid pool, it is necessary to close the gap between panel members through which the electrodeposition liquid cannot sufficiently pass. It is set based on viscosity. That is, in a portion where the interval between the panel members is narrow (a portion where the distance is equal to or less than the predetermined distance α), it is difficult to remove the electrodeposition liquid when the vehicle body 10 is actually pulled up from the treatment tank 11. It is handled as a point. Further, when calculating the predetermined distance α [mm] based on the viscosity of the electrodeposition liquid, it is possible to calculate using the following formulas (1) and (2), for example. In addition, γ is the surface tension [mN / m] × 10 ⁵ of the electrodeposition liquid, and γ ₀ is the constant [mN / m] × 10 ⁵ of the electrodeposition liquid. T is the use temperature of the electrodeposition liquid [° C.], T _c is the critical temperature of the electrodeposition liquid [° C.], and k is a coefficient (for example, due to the surface roughness of the panel member, presence or absence of plating treatment, etc. 0.001 to 0.01).
γ = γ ₀ (1-T / T _c ) ^9/11 (1)
α = k × γ (2)

  In the integration process described above, since the nodes whose node distance is equal to or less than the predetermined distance α are associated as adjacent nodes, the adjacent nodes are also associated as adjacent nodes even in the places to be joined by spot welding or arc welding. Will be. That is, the spot welding or the like is basically designed so that the panel members are in contact with each other, and therefore the nodal distance between neighboring nodes is designed to be equal to or less than the predetermined distance α. As described above, since the welding location is less than the predetermined distance α, the welding location can be reflected in the vehicle body analysis model using the integration process described above, and the work cost when constructing the vehicle body analysis model is reduced. Is possible.

  Subsequently, the above-described panel analysis model integration processing procedure will be described with reference to a flowchart. Here, FIG. 7 is a flowchart showing a procedure for integrating the panel analysis models. As shown in FIG. 7, in step S1, the part number I is set to 1, and in step S2, the reference panel analysis model I is set based on the part number I. Subsequently, in step S3, the node number i is set to 1, and in step S4, the reference node i is set based on the node number i. Next, in step S5, the target node j of another panel analysis model close to the reference node i is searched, and in step S6, the node distance Dij between the reference node i and the target node j is calculated. In subsequent step S7, it is determined whether or not the nodal distance Dij is equal to or less than a predetermined distance α (distance determination step). If it is determined in step S7 that the node distance Dij is equal to or smaller than the predetermined distance α, the process proceeds to step S8, and after associating the reference node i and the target node j as adjacent nodes (model integration step), step S9. Proceed to On the other hand, if it is determined in step S7 that the node distance Dij exceeds the predetermined distance α, the process proceeds to step S9 without associating the reference node i and the target node j as adjacent nodes. In step S9, the node number i is counted and updated to a new node number i. In subsequent step S10, it is determined whether or not the node number i exceeds the maximum value n. In this step S10, when the node number i is equal to or less than the maximum value n, the determination process from step S4 is executed until the node number i exceeds the maximum value n. That is, for all the nodes (1 to n) included in the panel analysis model I, the presence or absence of the node j of another panel analysis model associated as an adjacent node is determined.

  If the node number i exceeds the maximum value n in step S10, the process proceeds to step S11, where the part number I is counted and updated to a new part number I. Subsequently, in step S11, it is determined whether or not the part number I exceeds the maximum value N. If the part number I is equal to or less than the maximum value N in step S11, the determination process from step S2 is executed until the part number I exceeds the maximum value N. That is, the integration process is executed for all panel analysis models (1 to N) constituting the vehicle body 10. Thereby, one vehicle body analysis model is constructed from all the panel analysis models (1 to N).

  Thus, when the vehicle body analysis model is constructed, the gas-liquid determination process (gas-liquid determination step) is executed by the gas-liquid determination unit 31 of the arithmetic device 13. The gas-liquid determination process is a process for determining whether each node constituting the vehicle body analysis model is a node in contact with the electrodeposition liquid (liquid) or a node in contact with air (gas). Here, FIG. 8 is a flowchart showing the execution procedure of the gas-liquid determination process for predicting air accumulation. As shown in FIG. 8, in step S21, attribute data of all nodes constituting the vehicle body analysis model is set to air. Subsequently, in step S22, the node located at the end is set as the boundary node, and in step S23, the attribute data of the boundary node is changed to the electrodeposition liquid. In addition, the node located at the end means a node located at an edge portion of the vehicle body 10, that is, a node located at the edge of the panel member or the edge of the hole formed in the panel member. It is a node that contacts the electrodeposition solution unconditionally when submerged. In other words, the node located at the end is a node that is not surrounded by the surface elements, that is, a node that is not shared by the four surface elements when the surface element is formed of a quadrangle.

  Next, in step S24, it is determined whether or not there is an unanalyzed boundary node for the presence or absence of an adjacent node described later. If there is an unanalyzed boundary node in step S24, the process proceeds to step S25, where the boundary node to be analyzed is set. Subsequently, in step S26, it is determined whether there is an adjacent node adjacent to the boundary node. In step S26, if there is an adjacent node, the process proceeds to step S27, where the Z coordinate values of the boundary node and the adjacent node are compared. In the subsequent step S28, when the adjacent node is higher than the boundary node, the attribute data of the adjacent node is maintained as air, whereas when the adjacent node is at a height position equal to or lower than the boundary node, the attribute data of the adjacent node is air. To electrodeposition solution. That is, since the specific gravity of the electrodeposition liquid is larger than the specific gravity of air, when there is a boundary node in contact with the electrodeposition liquid above the adjacent node, the electrodeposition liquid flows from the boundary node toward the adjacent node below. Will move. For this reason, when the adjacent node is lower than the boundary node, the attribute data of the adjacent node is rewritten from the air to the electrodeposition liquid. Subsequently, in step S29, the adjacent node whose attribute data is changed to the electrodeposition liquid is set as a new boundary node. The gas-liquid determination is repeated from step S24 until there are no unanalyzed boundary nodes, and the attribute data of all nodes is divided into the electrodeposition liquid and air.

  The attribute data predicted for each node is output to the display device 15 via the post processing unit 32 of the arithmetic device 13. In the post processing unit 32, for example, a process of expressing the nodes in contact with the electrodeposition liquid and the nodes in contact with the air according to hue, shading, or the like is executed.

  Subsequently, the above-described gas-liquid determination process will be described using the analysis model of FIG. Here, FIG. 9 is an explanatory diagram showing a situation when the gas-liquid determination process is executed for the integrated analysis model K. FIG. FIGS. 10A to 10C are explanatory diagrams showing the situation when the gas-liquid determination process is executed for the unintegrated panel analysis models I and J. FIG. First, as shown in FIG. 9, in the integrated analysis model K, since the nodes i5 and j5 are located at the ends, the attribute data of the nodes i5 and j5 is the electrodeposition liquid. Further, since the node i4 adjacent to the node i5 is located above the node i5, the attribute data of the node i4 is maintained as air. Similarly, since the node j4 adjacent to the node j5 is located above the node j5, the attribute data of the node j4 is maintained as air. Since the nodes i4 and j4 whose attribute data is air are not set as new boundary nodes, the attribute data of the other nodes i1 to i3 and j1 to j3 are also maintained as air. That is, for the integrated analysis model K, an air pocket is predicted to occur.

  On the other hand, as shown in FIG. 10A, in the unintegrated panel analysis models I and J, since the nodes i1, i5, j1, and j5 are located at the ends, the attributes of the nodes i1, i5, j1, and j5 are attributed. Data is the electrodeposition solution. Further, as shown in FIG. 10B, since the height of the node i2 adjacent to the node i1 is equal to or less than the node i1, the attribute data of the node i2 is changed from air to the electrodeposition liquid. Similarly, since the height of the node j2 adjacent to the node j1 is equal to or less than the node j1, the attribute data of the node j2 is changed from air to the electrodeposition liquid. Then, since the nodes i2 and j2 whose attribute data is the electrodeposition liquid are set as new boundary nodes, other nodes i3, i4, i4, as indicated by white arrows in FIG. The attribute data of j3 and j4 is also changed to the electrodeposition liquid. That is, for the unintegrated panel analysis models I and J, it is predicted that no air pool will occur.

  As described so far, in the present invention, the presence or absence of adjacent nodes between panel analysis models is determined based on the node distance, so that it is difficult for air to pass through other than the joints where spot welding or the like is performed. Can be reflected in the vehicle body analysis model. Then, by performing the gas-liquid determination process using this vehicle body analysis model, it is possible to improve the prediction accuracy of the air pocket. That is, as shown in FIG. 10C, when the prediction is made while leaving a gap between the panel analysis models I and J, air is discharged in the direction of arrow A through this gap. However, since the gap between the panel analysis models I and J is a narrow gap of a predetermined distance α or less, the gap cannot actually be sufficiently discharged. In other words, predicting an air pool while using this gap as a passage for air has resulted in an erroneous determination that an air pool does not occur despite the occurrence of an air pool. On the other hand, as shown in FIG. 9, when the simulation method or simulation program of the present invention is used, the nodes constituting the gap of the predetermined distance α or less are reflected as the adjacent nodes. The analysis model K can be configured by closing the gap, and a correct result can be derived that an air pocket is generated.

  Next, the prediction of the liquid pool will be described. Here, FIG. 11A is an explanatory diagram showing the panel analysis models O and P before integration, and FIG. 11B is an explanatory diagram showing the analysis model Q after integration. As shown in FIG. 11A, a panel analysis model O having nodes o1 to o5 and a panel analysis model P having nodes p1 to p5 are provided. By processing these panel analysis models O and P in accordance with the flowchart of FIG. 7, as shown in FIG. 11B, the panel analysis models O and P become nodes o1 to o3 and p1 to be adjacent nodes. It is integrated into one analysis model Q via p3. Note that, when an analysis model for predicting a liquid pool is constructed, as described above, the predetermined distance α for determining an adjacent contact is set based on the viscosity of the electrodeposition liquid.

  Next, FIG. 12 is a flowchart showing an execution procedure of a gas-liquid determination process for predicting a liquid pool. As shown in FIG. 12, in step S31, attribute data of all nodes constituting the analysis model is set in the electrodeposition liquid. Subsequently, in step S32, the node located at the end is set as the boundary node, and in step S33, the attribute data of the boundary node is changed to air. In addition, the node located at the end means a node located at an edge portion of the vehicle body 10, that is, a node located at the edge of the panel member or the edge of the hole formed in the panel member. It is a node that contacts the air unconditionally when pulled up. In other words, the node located at the end is a node that is not surrounded by the surface elements, that is, a node that is not shared by the four surface elements when the surface element is formed of a quadrangle.

  Next, in step S34, it is determined whether or not there is an unanalyzed boundary node for the presence or absence of an adjacent node described later. If there is an unanalyzed boundary node in step S34, the process proceeds to step S35, and the boundary node to be analyzed is set. Subsequently, in step S36, it is determined whether there is an adjacent node adjacent to the boundary node. If there is an adjacent node in step S36, the process proceeds to step S37, where the Z coordinate values of the boundary node and the adjacent node are compared. In the subsequent step S38, when the adjacent node is higher than the boundary node, the attribute data of the adjacent node is changed from the electrodeposition liquid to air. On the other hand, when the adjacent node is lower than the boundary node, the attribute of the adjacent node is changed. Data is maintained as an electrodeposition solution. In other words, since the specific gravity of air is smaller than the specific gravity of the electrodeposition liquid, when there is a boundary node in contact with air below the adjacent node, air moves from the boundary node toward the adjacent node above. Become. For this reason, when the adjacent node is higher than the boundary node, the attribute data of the adjacent node is rewritten from the electrodeposition liquid to the air. Subsequently, in step S39, the adjacent node whose attribute data is changed to air is set as a new boundary node. The gas-liquid determination is repeated from step S34 until there are no unanalyzed boundary nodes, and the attribute data of all nodes is divided into the electrodeposition liquid and air.

  This gas-liquid determination process will be described using the analysis model of FIG. Here, FIG. 13 is an explanatory diagram showing a situation when the gas-liquid determination process is executed for the integrated analysis model Q. FIG. FIGS. 14A to 14C are explanatory diagrams showing the situation when the gas-liquid determination process is executed for the unintegrated panel analysis models O and P. FIG. First, as shown in FIG. 13, in the integrated analysis model Q, since the nodes o5 and p5 are located at the ends, the attribute data of the nodes o5 and p5 is air. Further, since the node o4 adjacent to the node o5 is positioned below the node o5, the attribute data of the node o4 is maintained as the electrodeposition liquid. Similarly, since the node p4 adjacent to the node p5 is located below the node p5, the attribute data of the node p4 is maintained as the electrodeposition liquid. Since the nodes o4 and p4 whose attribute data is the electrodeposition liquid are not set as new boundary nodes, the attribute data of the other nodes o1 to o3 and p1 to p3 are also maintained as the electrodeposition liquid. Is done. That is, for the integrated analysis model Q, it is predicted that a liquid pool will occur.

  On the other hand, as shown in FIG. 14A, in the unintegrated panel analysis models O and P, since the nodes o1, o5, p1, and p5 are located at the ends, the attributes of the nodes o1, o5, p1, and p5 are determined. The data is air. Further, as shown in FIG. 14B, since the height of the node o2 adjacent to the node o1 is equal to or higher than the node o1, the attribute data of the node o2 is changed from the electrodeposition liquid to air. Similarly, since the height of the node p2 adjacent to the node p1 is not less than the node p1, the attribute data of the node p2 is changed from the electrodeposition liquid to air. Since the nodes o2 and p2 whose attribute data is air are set as new boundary nodes, the other nodes o3, o4, p3 are indicated by the white arrows in FIG. The attribute data of p4 is also changed to air. That is, for the unintegrated panel analysis models O and P, it is predicted that no liquid pool will occur.

  As described above, in the present invention, since the presence or absence of adjacent nodes between the panel analysis models is determined based on the node distance, the electrodeposition liquid passes through other than the joints where spot welding or the like is performed. Difficult parts can be reflected in the vehicle body analysis model. Then, by performing the gas-liquid determination process using this vehicle body analysis model, it is possible to increase the prediction accuracy of the liquid pool. That is, as shown in FIG. 14C, when the prediction is made while leaving a gap between the panel analysis models O and P, the electrodeposition liquid is discharged in the direction of arrow A through this gap. However, since the gap between the panel analysis models O and P is a narrow gap of a predetermined distance α or less, it is actually a gap where the electrodeposition liquid cannot be sufficiently discharged. In other words, predicting the liquid pool after using this gap as a path for the electrodeposition liquid has resulted in an erroneous determination that the liquid pool does not occur even though the liquid pool is generated. On the other hand, as shown in FIG. 13, when the simulation method of the present invention is used, the nodes constituting the gap of the predetermined distance α or less are reflected as the adjacent nodes, so that it becomes a path for the electrodeposition liquid. The analysis model Q can be configured by closing the gap, and a correct result that a liquid pool is generated can be derived.

  It goes without saying that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. For example, in the above description, the analysis model is integrated using the node elements, but the present invention is not limited to this, and the analysis model may be integrated using the surface elements. In this case, after setting the representative points of the surface elements (for example, the center of gravity, inner center, outer center, etc.), whether or not to associate each surface element as an adjacent element using the coordinate data of the representative point A determination is made. In the above description, the predetermined distance α serving as a reference for determining adjacent nodes is set based on the viscosity of the electrodeposition liquid or air. May be set. Furthermore, when integrating the panel analysis model, it is determined whether or not the node distance is equal to or less than the predetermined distance α after searching for the target node close to the reference node. Alternatively, an adjacent node within a predetermined distance α from the reference node may be directly searched.

  In the above description, the vehicle body 10 is cited as a workpiece. However, the present invention is not limited to this, and other components such as a case may be used as the workpiece. Furthermore, in the illustrated case, the surface shape of the panel member is represented by a rectangular surface element, but the present invention is not limited to this, and a panel analysis model may be configured using surface elements such as triangles and pentagons. good. Although the electrodeposition coating process has been described as an example, the simulation method and simulation program of the present invention may be applied to a simple dipping coating process, and plating that forms a metal film on a workpiece. You may apply with respect to a process.

10 Body (work)
11 Treatment tank 24 Front floor (panel member)
25 Center floor (panel material)
26 Rear floor (panel member)
α Predetermined distance I Panel analysis model (analysis model)
i1 to i15 Node elements (elements)
J Panel analysis model (analysis model)
j1 to j15 Node elements (elements)
K analysis model O panel analysis model (analysis model)
o1 to o5 Node elements (elements)
P Panel analysis model (analysis model)
p1 to p5 Node elements (elements)
Q Analysis model

Claims (4)

Simulation that is executed by a simulation device and predicts an air pool when a work constituted by a plurality of panel members is submerged in a processing tank in which processing liquid is stored, or a liquid pool when the work is lifted from the processing tank. A method,
A distance determination step for determining whether or not there is an element of another analysis model within a predetermined distance from an element of one analysis model, using an analysis model of each panel member composed of a plurality of elements;
A model integration step of connecting elements existing within the predetermined distance and integrating the one analysis model and the other analysis model;
Each element constituting the integrated analysis model, possess the treatment liquid and the gas-liquid determination step of determining whether in contact with any of the air, and
The simulation method according to claim 1, wherein the predetermined distance is set based on a viscosity of the processing liquid or air . In the simulation method of claim 1 Symbol placement,
The element constituting the analysis model is a plurality of surface elements that divide the surface shape of the panel member, or a plurality of node elements provided at the vertices of the surface elements. Simulation that is executed by a simulation device and predicts an air pool when a work constituted by a plurality of panel members is submerged in a processing tank in which processing liquid is stored, or a liquid pool when the work is lifted from the processing tank. A program,
A distance determination step for determining whether or not there is an element of another analysis model within a predetermined distance from an element of one analysis model, using an analysis model of each panel member composed of a plurality of elements;
A model integration step of connecting elements existing within the predetermined distance and integrating the one analysis model and the other analysis model;
Each element constituting the integrated analysis model, possess the treatment liquid and the gas-liquid determination step of determining whether in contact with any of the air, and
The simulation program characterized in that the predetermined distance is set based on the viscosity of the processing liquid or air . In the simulation program according to claim 3 ,
The simulation program characterized in that the elements constituting the analysis model are a plurality of surface elements that divide the surface shape of the panel member, or a plurality of node elements provided at the vertices of the surface elements.

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