WO2024108637A1 - 一种具有异型管段的管道力学计算方法及装置、分析方法及装置 - Google Patents

一种具有异型管段的管道力学计算方法及装置、分析方法及装置 Download PDF

Info

Publication number
WO2024108637A1
WO2024108637A1 PCT/CN2022/135739 CN2022135739W WO2024108637A1 WO 2024108637 A1 WO2024108637 A1 WO 2024108637A1 CN 2022135739 W CN2022135739 W CN 2022135739W WO 2024108637 A1 WO2024108637 A1 WO 2024108637A1
Authority
WO
WIPO (PCT)
Prior art keywords
special
node
pipeline
displacement
shaped pipe
Prior art date
Application number
PCT/CN2022/135739
Other languages
English (en)
French (fr)
Inventor
刘树斌
刘诗华
刘宝君
陈丽
刘健
白国宇
Original Assignee
中国核电工程有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 中国核电工程有限公司 filed Critical 中国核电工程有限公司
Publication of WO2024108637A1 publication Critical patent/WO2024108637A1/zh

Links

Images

Classifications

    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06FELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06FELECTRIC DIGITAL DATA PROCESSING
    • G06F30/00Computer-aided design [CAD]
    • G06F30/20Design optimisation, verification or simulation
    • G06F30/23Design optimisation, verification or simulation using finite element methods [FEM] or finite difference methods [FDM]
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06FELECTRIC DIGITAL DATA PROCESSING
    • G06F2113/00Details relating to the application field
    • G06F2113/14Pipes
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06FELECTRIC DIGITAL DATA PROCESSING
    • G06F2119/00Details relating to the type or aim of the analysis or the optimisation
    • G06F2119/14Force analysis or force optimisation, e.g. static or dynamic forces

Definitions

  • the present invention relates to the technical field of pipeline design, and in particular to a pipeline mechanics calculation method and device, and an analysis method and device with special-shaped pipe sections.
  • the current pipeline calculation software uses one-dimensional pipeline beam units for model calculation, including straight pipe beam units and curved pipe beam units, which are both line units.
  • pipeline and equipment calculations are usually performed separately. First, the pipeline calculation is performed to obtain the thrust of the pipeline on the equipment, and then the load combination calculation is performed. Then, the combined load is used to perform stress analysis and evaluation on the equipment.
  • Some programs can also use shell units to calculate special components. However, the method of establishing shell unit components is relatively complicated. Some require input node coordinates one node at a time, and then a detailed description of each shell unit is made. Some need to use a separate modeling module to create a shell unit model, and then the main program makes this shell unit component into a stiffness matrix and brings it into the pipeline model for calculation.
  • the shell unit model can only obtain the displacement and internal force of the connection points at both ends. After obtaining the pipeline solution, the force on the component is added to the equipment to calculate the shell unit component separately. It can be seen that the inability of existing pipeline calculation software to conveniently establish shell unit components is a major technical problem.
  • the method of directly placing the shell unit component model into the pipeline problem is not problematic in principle.
  • all common finite element programs can do this, but the problem is that the work efficiency is extremely low, including: modeling efficiency, technical methods for connecting pipelines and shell components, standard processing requirements during the process, and implementation of standard requirements during evaluation.
  • the technologies involved here include: user interaction, or definition of pipeline description methods, pipeline program calculations, including support requirements limited by standards, correspondence between calculation methods required by specifications and pipeline loads, modeling methods for pipeline components, especially special-shaped pipes, and the correspondence between pipeline units and shell units.
  • the technical problem to be solved by the present invention is to provide a pipeline mechanics calculation method and device that can complete the calculation and evaluation of pipelines and special-shaped pipe shell components at one time, thereby greatly improving the efficiency of pipeline design work.
  • the present invention provides a pipeline mechanics calculation method with a special-shaped pipe section, comprising:
  • a pipeline beam model consisting of multiple pipeline beam units and the node information of each pipeline beam unit is generated, wherein the components correspond to the pipeline beam units one by one.
  • the mesh model of the special-shaped pipe section is used to replace the pipe beam unit at the corresponding position in the pipe beam model to form a hybrid model.
  • the hybrid model is subjected to finite element calculation to obtain the displacement of each node of the hybrid model.
  • the node displacement of the pipeline beam unit the node internal force of the pipeline beam unit is calculated.
  • the stress of each shell unit is calculated.
  • the stress of the pipe beam unit is calculated based on the internal force of the nodes of the pipe beam unit.
  • the special-shaped pipe section includes a bend pipe.
  • Calculating the material density of the elbow specifically includes:
  • the axial reduced density coefficient fac a ′ of the elbow is calculated.
  • the elbow forms n elbow segments.
  • w a ′′ wa ′ ⁇ fac a ⁇ fac a ′.
  • the special-shaped pipe section includes a tee pipe
  • Calculating the material density of the tee pipe specifically includes:
  • the area conversion coefficient fac b of the main pipe or branch pipe is calculated.
  • A′ is the area calculated after the main pipe or branch pipe model is replaced, taking into account the missing or excess area.
  • A′ is specifically the sum of the shell unit areas of the main pipe or branch pipe calculated based on the grid node information of the main pipe or branch pipe in the grid model.
  • the special-shaped pipe section comprises a tapered pipe.
  • Calculating the material density of the cone includes:
  • R c is the radius of the large end of the cone tube
  • r c is the radius of the small end of the cone tube
  • L c is the length of the cone tube
  • N c is the number of circumferential segments of the cone tube
  • a node of the pipeline beam unit at the connection between the grid model of the special-shaped pipe section and the pipeline beam unit is set as a master node, and each node of the grid model of the special-shaped pipe section corresponding to the master node at the connection between the grid model of the special-shaped pipe section and the pipeline beam unit is set as a slave node,
  • Finite element calculation is performed on the hybrid model to obtain the displacement of each node of the hybrid model, including: at the connection between the grid model of the special-shaped pipe section and the pipeline beam unit, only the displacement of the main node is calculated,
  • the method of calculating the stress of each shell unit according to the grid node displacement of the grid model of the special-shaped pipe section specifically includes:
  • the displacement of each slave node corresponding to the master node is calculated
  • the displacement of each slave node and the displacement of other grid nodes of the grid model of the special-shaped pipe section obtained in the finite element calculation constitute the grid node displacement of the grid model of the special-shaped pipe section.
  • the stress of each shell unit is calculated according to the mesh node displacement of the mesh model of the special-shaped pipe section.
  • the method before calculating the displacement of each slave node corresponding to the master node according to the displacement of the master node, the method further includes: determining whether the working condition is a non-temperature working condition or a temperature working condition,
  • the displacement of each slave node corresponding to the master node is calculated using the following formula according to the displacement of the master node:
  • d is the displacement of the master node
  • d′ is the displacement of the slave node corresponding to the master node
  • a is the conversion matrix for converting the master node displacement to the slave node displacement
  • the displacement of each slave node corresponding to the master node is calculated using the following formula according to the displacement of the master node:
  • alf is the thermal expansion coefficient of the pipe material.
  • the present invention also provides a pipeline mechanics analysis method having a special-shaped pipe section, comprising:
  • the above pipeline mechanics calculation method with special-shaped pipe sections is used to calculate the stress of each shell unit and the stress of each pipeline beam unit.
  • the present invention also provides a pipeline mechanics calculation device having a special-shaped pipe section, comprising:
  • the pipeline beam generation module is used to generate a pipeline beam model composed of multiple pipeline beam units and the node information of each pipeline beam unit according to the parameter information of each component in the pipeline, wherein the components correspond to the pipeline beam units one by one.
  • the shell generation module is used to obtain the mesh division information of the special-shaped pipe section to be analyzed in detail, as well as its node information in the pipe beam model, generate a mesh model of the special-shaped pipe section formed by splicing multiple shell units, and the mesh node information in the mesh model,
  • a replacement module is used to replace the pipe beam unit at the corresponding position in the pipe beam model with the grid model of the special-shaped pipe segment to form a hybrid model.
  • the shell parameter forming module is used to calculate the material density of the special-shaped pipe segment and replace the line density in the parameter information of the special-shaped pipe segment to form the updated parameter information of the special-shaped pipe segment.
  • the finite element calculation module is used to perform finite element calculation on the hybrid model according to the working condition information of the pipeline to be calculated and the parameter information of each component in the pipeline, obtain the displacement of each node of the hybrid model, calculate the node internal force of the pipeline beam unit according to the node displacement of the pipeline beam unit, and calculate the stress of each shell unit according to the grid node displacement of the grid model of the special-shaped pipe section.
  • the stress calculation module calculates the stress of the pipeline beam unit according to the node internal force of the pipeline beam unit.
  • an interface module is further included, which is used to receive the working condition information of the pipeline to be calculated and the parameter information of each component and transmit them to the pipeline beam generation module and the finite element calculation module, and also transmit the parameter information of the special-shaped pipe section to the shell generation module and the shell parameter formation module respectively;
  • the special-shaped pipe section includes a bend pipe.
  • the shell parameter forming module calculates the material density of the elbow, specifically including:
  • the axial reduced density coefficient fac a ′ of the elbow is calculated.
  • the elbow forms n elbow segments.
  • w a ′′ wa ′ ⁇ fac a ⁇ fac a ′.
  • the special-shaped pipe section includes a tee pipe
  • the shell parameter forming module is also electrically connected to the shell generating module, which calculates the material density of the tee pipe, specifically including:
  • the area conversion coefficient fac b of the main pipe or branch pipe is calculated.
  • A′ is the area calculated after the main pipe or branch pipe model is replaced, taking into account the missing or excess area.
  • A′ is specifically the sum of the shell unit areas of the main pipe or branch pipe calculated based on the grid node information of the main pipe or branch pipe in the grid model.
  • the special-shaped pipe section comprises a tapered pipe.
  • the shell parameter forming module is also electrically connected to the shell generating module, which calculates the material density of the cone tube, specifically including:
  • R c is the radius of the large end of the cone tube
  • r c is the radius of the small end of the cone tube
  • L c is the length of the cone tube
  • N c is the number of circumferential segments of the cone tube
  • the shell parameter forming module includes a material density calculation module and a parameter updating module,
  • the material density calculation module is electrically connected to the interface module and is used to calculate the material density of the special-shaped pipe section according to the parameter information of the special-shaped pipe section.
  • the parameter updating module is electrically connected to the material density calculating module, and is used to replace the line density in the parameter information of the special-shaped pipe segment with the material density of the special-shaped pipe segment to form updated parameter information of the special-shaped pipe segment.
  • a node of the pipeline beam unit at the connection between the grid model of the special-shaped pipe section and the pipeline beam unit is set as a master node, and each node of the grid model of the special-shaped pipe section corresponding to the master node at the connection between the grid model of the special-shaped pipe section and the pipeline beam unit is set as a slave node,
  • the finite element calculation module includes a total node displacement calculation module, a grid node displacement formation module, a beam unit internal force calculation module and a shell unit stress calculation module.
  • the total node displacement calculation module is used to perform finite element calculation on the hybrid model to obtain the displacement of each node of the hybrid model, which includes: at the connection between the grid model of the special-shaped pipe section and the pipeline beam unit, only the displacement of the main node is calculated,
  • the grid node displacement forming module is electrically connected to the total node displacement calculating module, and is used to calculate the displacement of each slave node corresponding to the master node according to the displacement of the master node, and is also used to aggregate the displacement of each slave node and other grid node displacements of the grid model of the special-shaped pipe section obtained in the finite element calculation to form the grid node displacement of the grid model of the special-shaped pipe section.
  • the beam unit internal force calculation module is electrically connected to the total node displacement calculation module and is used to calculate the node internal force of the pipeline beam unit according to the node displacement of the pipeline beam unit.
  • the shell unit stress calculation module is electrically connected to the grid node displacement forming module, and is used to calculate the stress of each shell unit according to the grid node displacement of the grid model of the special-shaped pipe section.
  • the finite element calculation module further includes a judgment module, which is electrically connected between the interface module and the grid node displacement forming module and is used to judge whether the working condition is a non-temperature working condition or a temperature working condition.
  • the grid node displacement forming module is triggered to calculate the displacement of each slave node corresponding to the master node according to the displacement of the master node using the following formula:
  • d is the displacement of the master node
  • d′ is the displacement of the slave node corresponding to the master node
  • a is the conversion matrix for converting the master node displacement to the slave node displacement
  • the grid node displacement forming module is triggered to calculate the displacement of each slave node corresponding to the master node according to the displacement of the master node using the following formula:
  • alf is the thermal expansion coefficient of the pipe material.
  • the mesh node displacement forming module includes a shell slave node displacement calculation module and a shell node displacement summary module.
  • the shell slave node displacement calculation module is electrically connected to the total node displacement calculation module, and is used to calculate the displacement of each slave node corresponding to the master node according to the displacement of the master node.
  • the shell node displacement summary module is electrically connected to the shell slave node displacement calculation module and the total node displacement calculation module, respectively, and is used to summarize the displacement of each slave node and the displacement of other grid nodes of the grid model of the special-shaped pipe section obtained in the finite element calculation to form the grid node displacement of the grid model of the special-shaped pipe section.
  • the present invention also provides a pipeline mechanics analysis device with a special-shaped pipe section, comprising the above-mentioned pipeline mechanics calculation device with a special-shaped pipe section and a stress assessment module.
  • the stress assessment module is electrically connected to the finite element calculation module and the stress calculation module of the pipeline mechanics calculation device with the special-shaped pipe section, and is used to perform stress assessment on the pipeline with the special-shaped pipe section according to the stress of each shell unit and the stress of each pipeline beam unit.
  • a finite element mesh model is generated (after meshing, each adjacent four nodes constitute a shell unit), and the pipe beam unit at the corresponding position in the pipe beam model is replaced.
  • the formed hybrid model is solved by finite element calculation to obtain the displacement of each node in the hybrid model.
  • the node displacement of the beam unit in the hybrid model the node internal force of the pipe beam unit can be calculated, and then the stress of the pipe beam unit is calculated.
  • the internal force (i.e., stress) of each shell unit can be calculated.
  • the present invention completes the calculation and evaluation of the pipe beam unit and the special-shaped pipe shell parts at one time, and there is no unnecessary conservative combination processing process in the middle, which greatly improves the work efficiency of the pipeline design. And compared with the method of using one-dimensional pipe beam units for model calculation, the calculation accuracy of the present invention is greatly improved.
  • FIG1 is a flow chart of a pipeline mechanics calculation method with a special-shaped pipe section provided in Example 1 of the present invention
  • FIG2 is a schematic diagram of a cross-sectional grid of a pipeline
  • FIG3 is a schematic diagram of axial segmentation and meshing of a bent pipe
  • Fig. 4 is a cross-sectional view of a-a in Fig. 3;
  • FIG5 is a schematic diagram of the structure of a three-way pipe
  • FIG6 is a schematic diagram showing the calculation of the actual area of a three-way main pipe
  • FIG7 is a schematic diagram of a gridded cone
  • FIG8 is a schematic diagram of the master and slave nodes of the connection surface between the tube beam unit and the shell unit;
  • FIG9 is a block diagram of a pipeline mechanics calculation device with a special-shaped pipe section provided in Example 2 of the present invention.
  • FIG10 is a diagram of a pipeline model with a special-shaped shell and tube component established by the pipeline program of the present invention.
  • FIG. 11 is a statement diagram of the pipeline beam topic in the pipeline program of the present invention.
  • this embodiment provides a pipeline mechanics calculation method with a special-shaped pipe section, including:
  • a pipeline beam model consisting of multiple pipeline beam units and the node information of each pipeline beam unit is generated, wherein the components correspond to the pipeline beam units one by one.
  • the mesh model of the special-shaped pipe section is used to replace the pipe beam unit at the corresponding position in the pipe beam model to form a hybrid model.
  • the hybrid model is subjected to finite element calculation to obtain the displacement of each node of the hybrid model.
  • the node displacement of the pipeline beam unit the node internal force of the pipeline beam unit is calculated.
  • the stress of each shell unit is calculated.
  • the stress of the pipe beam unit is calculated based on the internal force of the nodes of the pipe beam unit.
  • the technology of the present invention is one of the multiple processes in the computer program algorithm for pipeline calculation.
  • Most of the previous pipeline programs used one-dimensional beam units to simulate pipelines, including straight pipe beam units and special-shaped pipe (including elbows, tees, tapered pipes, etc.) beam units, which are all line units.
  • the technology of the present invention is a technical means that needs to be adopted when converting special-shaped pipe beam units into three-dimensional shell unit models to meet the requirements of the mixed model of pipeline beam and shell unit components in finite element calculation.
  • a finite element mesh model is generated (after meshing, each adjacent four nodes constitute a shell unit) to replace the pipe beam unit at the corresponding position in the pipe beam model.
  • the formed hybrid model is solved by finite element calculation to obtain the displacement of each node in the hybrid model.
  • the node displacement of the beam unit in the hybrid model the node internal force of the pipe beam unit can be calculated, and then the stress of the pipe beam unit can be calculated.
  • the internal force (i.e. stress) of each shell unit can be calculated.
  • the present invention completes the calculation and evaluation of the pipe beam unit and the special-shaped pipe shell parts at one time, and there is no unnecessary conservative combination processing process in the middle, which greatly improves the work efficiency of pipeline design. And compared with the method of using one-dimensional pipe beam unit for model calculation, the calculation accuracy of the present invention is greatly improved.
  • the present invention proposes the above-mentioned pipeline mechanics calculation method, which can automatically convert heterogeneous pipe sections such as one-dimensional curved beam unit elbows (note: although it is a one-dimensional line unit, it actually describes a partial ring of a pipe with a known bending radius) into a three-dimensional shell unit model by adding simple input requirements to the original pipeline calculation problem data.
  • the original curved pipe unit has only three nodes (starting point, end point and reference point). After the conversion, it may become hundreds or thousands of nodes. Every four adjacent nodes are connected end to end in sequence to form a shell unit, and multiple shell units are spliced to form a three-dimensional shell unit model.
  • the process of discretizing a smooth circular pipe into a finite number of three-dimensional shell units is a pre-processing meshing technology of the finite element program, which is a well-known technology in the technical field.
  • the end of the beam unit is a node
  • the end of the shell unit is a surface composed of multiple nodes.
  • the technology of associating a point with a surface composed of multiple points is also a well-known technology in the field.
  • the present invention integrates these technologies into the modeling module of the pipeline calculation program.
  • the model automatically established by this method can automatically complete the calculation of the pipeline beam unit and the shell unit at the same time during the pipeline calculation process.
  • the structure of the program needs to meet the functional requirements of multiple units, and here it must meet various requirements for pipeline and shell unit calculations. It includes the pipe-beam processing and its connection method with the shell component, and also includes an accurate method for converting the mass density when the components in the pipeline are converted into shell units.
  • the material density of the target shell part needs to be determined.
  • all programs on the market require the linear density of the pipe, which includes the material weight of the pipe, generally steel, the weight of the working medium, and the weight of the insulation material.
  • the material density of the target shell part needs to be given.
  • the program usually multiplies the area of the shell by the thickness and then by the material density to get the weight of the shell element.
  • the general algorithm is to divide the linear density per unit length by the circumference of the pipeline and the thickness of the pipeline as the material density of the target shell part.
  • the cross section of the pipeline is shown in Figure 2:
  • the circle in the figure is a schematic diagram of the mid-surface of the pipeline, where the wall thickness of the pipeline is ignored, and the radius of the mid-surface is R.
  • the figure when the pipeline is divided into six segments in the circumferential direction is as follows.
  • the length L is the length of one side of the shell element, that is, the length of the broken line after segmentation.
  • the algorithm for converting the straight pipe material density from the given pipeline line density w after generalization to any number of circumferential segments is:
  • Shell element density: w′′ w′ ⁇ fac.
  • the applicant's preliminary research shows that the straight tube shell unit density processed in this way, no matter how many sections the pipeline is divided into circumferentially, the calculated pipe weight is correct.
  • this processing method has defects, and the weight of the converted model is different from the weight of the pipe beam model at the beginning.
  • the reason for the difference in the weight of the elbow shell unit model is that the weight of the curved pipe unit is equal to the linear weight of the pipeline multiplied by the arc length of the elbow.
  • the shell unit density calculated according to the above processing method after considering the shell unit area, the shell unit elbow weight obtained is less than the actual weight of the elbow.
  • the special-shaped pipe section includes a curved pipe.
  • the parameter information of the elbow includes:
  • the node information of the elbow in the pipeline beam model includes the node numbers and coordinate values of the start and end nodes and the reference nodes.
  • Calculating the material density of the elbow specifically includes:
  • the axial reduced density coefficient fac a ′ of the elbow is calculated.
  • the elbow forms n elbow segments.
  • w a ′′ wa ′ ⁇ fac a ⁇ fac a ′.
  • the special-shaped pipe section includes a three-way pipe.
  • the parameter information of the three-way pipe includes:
  • the node information of the tee pipe in the pipeline beam model includes the node numbers and coordinate values of the nodes where the branch pipe and the two main pipes intersect and the respective end nodes.
  • Calculating the material density of the special-shaped pipe section specifically includes:
  • the area conversion coefficient fac b of the main pipe or branch pipe is calculated.
  • A′ is the area calculated after the main pipe or branch pipe model is replaced, taking into account the missing or excess area.
  • A′ is specifically the sum of the shell unit areas of the main pipe or branch pipe calculated based on the grid node information of the main pipe or branch pipe in the grid model.
  • the number of segments of the branch pipe needs to be considered, as shown in Figure 6.
  • the figure shows that the main pipe is divided into 6 circumferential sections (only three sections are shown in the figure). Their influence should be considered when calculating the area of the main pipe later. There is a lack of material at the connection between the main pipe and the branch pipe, and this influence needs to be considered when calculating the area.
  • the entire branch pipe is divided into 12 sections, and only 6 sections need to be considered in the figure (the other 6 sections intersect with another main pipe).
  • the pipeline can be divided into two parts, a part with a length of L1 and a part with a length of l1 .
  • the area of the L part is calculated according to the ordinary straight pipe (circumferential hexagon perimeter ⁇ L1 ), and the part below r of the l1 part is also calculated according to the ordinary straight pipe ((circumferential hexagon perimeter/2) ⁇ l1 ).
  • the part below r needs to calculate the coordinates of the vertices of each shell unit point by point to obtain the average height and area of each trapezoid. It is also possible to directly call the coordinate values of each node of the main pipe to calculate the sum of the areas of each shell unit of the main pipe.
  • the tee uses the same method as the straight pipe to describe the pipeline linear density.
  • the calculation of the tee weight in the question is relatively simple, multiplying the length by the linear weight.
  • A D ⁇ ⁇ ⁇ (L 1 + l 1 )
  • the algorithm for A' is calculated according to the above two methods.
  • calculation method refers to the above two calculation methods for the main pipe, and will not be repeated here.
  • the special-shaped pipe section includes a tapered pipe.
  • the parameter information of the cone tube includes:
  • the node information of the tapered tube in the pipeline beam model includes the node numbers and coordinate values of the start and end nodes.
  • Calculating the material density of the cone tube specifically includes:
  • R c is the radius of the large end of the cone tube
  • r c is the radius of the small end of the cone tube
  • L c is the length of the cone tube
  • N c is the number of circumferential segments of the cone tube
  • tapered pipes also called tapered pipes
  • the algorithm for tapered pipes seems to be the same as that for straight pipes, but it is not.
  • its length is not the length of the reducer and reducer pipe elements input by the user, that is, L c in Figure 7.
  • the number of circumferential segments has an impact on the results.
  • the volume of each segment is calculated by multiplying the area of each segment by the average wall thickness.
  • the width of each segment should be calculated using the average width b.
  • the segment length is not L c , nor the length of the intersection of the two segments. It should be the length C of the center line in the middle of the dividing section in the figure (drawn with a dotted line in the figure). Its length:
  • H R c cos (360/2N)
  • h r c cos (360/2N)
  • the node of the pipeline beam unit at the connection between the grid model of the special-shaped pipe section and the pipeline beam unit is set as the main node
  • each node of the grid model of the special-shaped pipe section corresponding to the main node at the connection between the grid model of the special-shaped pipe section and the pipeline beam unit is set as the slave node.
  • Finite element calculation is performed on the hybrid model to obtain the displacement of each node of the hybrid model, including: at the connection between the grid model of the special-shaped pipe section and the pipeline beam unit, only the displacement of the main node is calculated,
  • the method of calculating the stress of each shell unit according to the grid node displacement of the grid model of the special-shaped pipe section specifically includes:
  • the displacement of each slave node corresponding to the master node is calculated
  • the displacement of each slave node and the displacement of other grid nodes of the grid model of the special-shaped pipe section obtained in the finite element calculation constitute the grid node displacement of the grid model of the special-shaped pipe section.
  • the stress of each shell unit is calculated based on the mesh node displacement of the mesh model of the special-shaped pipe section.
  • Nodes 8 and 9 constitute the pipeline beam unit, which is a one-dimensional line unit.
  • 21 to 26 are a circle of nodes on the boundary of the shell unit.
  • the displacement solutions of these nodes are not in the displacement unknowns of the structural equation of the finite element model. They are indirectly obtained from the displacement of node 9.
  • the usual solution process generally stops here. However, this result is not complete for temperature loads, and the effect of thermal expansion of rigid surfaces is missing.
  • the length R corresponding to each subordinate node affected by thermal expansion changes.
  • each slave node corresponding to the master node before calculating the displacement of each slave node corresponding to the master node according to the displacement of the master node, it also includes: judging whether the working condition is a non-temperature working condition or a temperature working condition,
  • the displacement of each slave node corresponding to the master node is calculated using the following formula according to the displacement of the master node:
  • d is the displacement of the master node
  • d′ is the displacement of the slave node corresponding to the master node
  • a is the conversion matrix for converting the master node displacement to the slave node displacement
  • the displacement of each slave node corresponding to the master node is calculated using the following formula according to the displacement of the master node:
  • alf is the thermal expansion coefficient of the pipe material.
  • the main node and its slave nodes mentioned above form a rigid surface. Because this rigid surface will not deform, this is correct for general load solutions, but it will cause problems for temperature loads.
  • the program only considers the thermal expansion along the axis when calculating, and cannot obtain the thermal expansion of the pipe in the circumferential direction.
  • the shell unit component after applying the temperature load, the shell unit component can obtain both the thermal expansion displacement in the axial direction and the thermal expansion displacement in the circumferential direction. At this time, unrealistic results will appear at the connection between the pipe beam unit and the shell unit component, because of this rigid surface. For this reason, it is necessary to consider the influence of the thermal displacement of each slave node.
  • the current pipeline calculation and analysis software cannot directly put the pipeline unit and the pipeline components described by the shell unit together for analysis and calculation.
  • it is necessary to divide it into multiple calculation conditions, such as self-weight conditions, temperature conditions, and earthquake conditions.
  • Different working conditions and different operating levels have different evaluation standards, which are reflected in different standard formulas.
  • many coefficients are used in the formula.
  • the bending moment of the pipeline beam obtained by the pipeline calculation is directly brought into the standard formula. Therefore, the pipeline beam unit does not need to directly obtain the actual stress.
  • the limit value required by the standard evaluation is the allowable stress.
  • the program must consider various factors (such as welding, component type, number of loading, etc.) The corresponding calculation.
  • Some of the influences of these conditions are considered by the coefficients given in the specification, such as the weld coefficient, which is related to the welding process and the connecting parts. There are some conservative factors here, which are inevitable when using the pipeline beam for calculation.
  • This technology can ensure that the weight calculated by these components is consistent with the pipeline subject and meet the calculation requirements of the entire subject.
  • the requirements for pipeline assessment can naturally be met, and the shell unit can directly obtain the unit stress, including membrane stress and bending stress.
  • the effect of the software developed by these two technologies is that the local results obtained by the usual software are more realistic, and the calculation and assessment of pipelines and equipment components can be completed at one time. Because the program is very simple to use, the work efficiency is greatly improved. At the same time, it eliminates a lot of conservatism in the design, making the design and construction of the pipeline and the entire project more economical and efficient.
  • the conventional pipeline calculation is to generate the pipeline beam unit according to the pipeline problem to be calculated.
  • This step is a conventional step in pipeline calculation and has nothing to do with the present invention. However, it is the basic condition of the present invention.
  • the problem includes elbows, tees and/or tapered pipes.
  • it is necessary to first specify how to determine the shell unit components in the problem, and to be able to distinguish the inlet and outlet of the elbow, tee and branch pipe.
  • the software needs to determine the original start and end nodes of this unit, the reference node number, the coordinate values of each node, and the diameter, bending radius, material, temperature, pressure and other information of this pipe unit.
  • the next step is to make a finite element solution model file, which should include various information of the shell unit, and cancel the corresponding curved pipe beam unit.
  • tee it should be defined whether it is a main pipe or a branch pipe, and the number of units required for the three parts. The three units must be logically connected. In the question, the three tee pipe beam units need to be cancelled.
  • the shell unit here can be described, the shell unit component type can be marked, and the straight pipe or curved pipe unit can be distinguished, and the main and branch pipes of the tee can also be distinguished.
  • the algorithm for the tee branch is similar.
  • Embodiment 2 is a diagrammatic representation of Embodiment 1:
  • This embodiment provides a pipeline mechanics analysis method with a special-shaped pipe section, including:
  • the stress of each shell unit and the stress of each pipe beam unit are calculated by using the pipeline mechanics calculation method with special-shaped pipe sections in Example 1.
  • Embodiment 3 is a diagrammatic representation of Embodiment 3
  • the present invention further provides a pipeline mechanics calculation device having a special-shaped pipe section, comprising:
  • the pipeline beam generation module 1 is used to generate a pipeline beam model composed of multiple pipeline beam units and node information of each pipeline beam unit according to the parameter information of each component in the pipeline, wherein the components correspond to the pipeline beam units one by one.
  • Shell generation module 2 is used to obtain the mesh division information of the special-shaped pipe section to be analyzed in detail, as well as its node information in the pipeline beam model, and generate a mesh model of the special-shaped pipe section formed by splicing multiple shell units, as well as the mesh node information in the mesh model.
  • the replacement module 3 is used to replace the pipe beam unit at the corresponding position in the pipe beam model with the grid model of the special-shaped pipe segment to form a hybrid model.
  • the shell parameter forming module 6 is used to calculate the material density of the special-shaped pipe segment and replace the line density in the parameter information of the special-shaped pipe segment to form the updated parameter information of the special-shaped pipe segment.
  • the finite element calculation module 4 is used to perform finite element calculation on the hybrid model according to the working condition information of the pipeline to be calculated and the parameter information of each component in the pipeline, obtain the displacement of each node of the hybrid model, calculate the node internal force of the pipeline beam unit according to the node displacement of the pipeline beam unit, and calculate the stress of each shell unit according to the grid node displacement of the grid model of the special-shaped pipe section.
  • the stress calculation module 5 calculates the stress of the pipeline beam unit according to the node internal force of the pipeline beam unit.
  • an interface module 7 is also included, which is used to receive the working condition information of the pipeline to be calculated and the parameter information of each component and transmit them to the pipeline beam generation module 1 and the finite element calculation module 4, and also transmit the parameter information of the special-shaped pipe section to the shell generation module 2 and the shell parameter formation module 6 respectively;
  • the special-shaped pipe section includes a curved pipe.
  • the parameter information of the elbow includes:
  • the node information of the elbow in the pipeline beam model includes the node numbers and coordinate values of the start and end nodes and the reference nodes.
  • the shell parameter forming module 6 calculates the material density of the elbow, specifically including:
  • the axial reduced density coefficient fac a ′ of the elbow is calculated.
  • the elbow forms n elbow segments.
  • w a ′′ wa ′ ⁇ fac a ⁇ fac a ′.
  • the special-shaped pipe section includes a three-way pipe.
  • the parameter information of the three-way pipe includes:
  • the node information of the tee pipe in the pipeline beam model includes the node numbers and coordinate values of the nodes where the branch pipe and the two main pipes intersect and the respective end nodes.
  • the shell parameter forming module 6 is also electrically connected to the shell generating module 2, and calculates the material density of the tee pipe, specifically including:
  • the circumferential reduced density coefficient fac b of the main pipe or branch pipe is calculated.
  • the area conversion coefficient fac b ′ of the main pipe or branch pipe is calculated.
  • A′ is the area calculated after the main pipe or branch pipe model is replaced, taking into account the missing or excess area.
  • A′ is specifically the sum of the shell unit areas of the main pipe or branch pipe calculated based on the grid node information of the main pipe or branch pipe in the grid model.
  • w b ′′ w b ′ ⁇ fac b ⁇ fac b ′.
  • the special-shaped pipe section includes a tapered pipe.
  • the parameter information of the cone tube includes:
  • the node information of the tapered tube in the pipeline beam model includes the node numbers and coordinate values of the start and end nodes.
  • the shell parameter forming module 6 calculates the material density of the cone tube, specifically including:
  • R c is the radius of the large end of the cone tube
  • r c is the radius of the small end of the cone tube
  • L is the length of the cone tube
  • N c is the number of circumferential segments of the cone tube
  • the shell parameter forming module 6 includes a material density calculation module 61 and a parameter updating module 62.
  • the material density calculation module 61 is electrically connected to the interface module 7 and is used to calculate the material density of the special-shaped pipe segment according to the parameter information of the special-shaped pipe segment.
  • the parameter updating module 62 is electrically connected to the material density calculating module 61 and is used to replace the line density in the parameter information of the special-shaped pipe segment with the material density of the special-shaped pipe segment to form updated parameter information of the special-shaped pipe segment.
  • the node of the pipeline beam unit at the connection between the grid model of the special-shaped pipe section and the pipeline beam unit is set as the main node
  • each node of the grid model of the special-shaped pipe section corresponding to the main node at the connection between the grid model of the special-shaped pipe section and the pipeline beam unit is set as the slave node.
  • the finite element calculation module 4 includes a total node displacement calculation module 41, a grid node displacement formation module 42, a beam unit internal force calculation module 44 and a shell unit stress calculation module 43.
  • the total node displacement calculation module 41 is used to perform finite element calculation on the hybrid model to obtain the displacement of each node of the hybrid model, which includes: at the connection between the grid model of the special-shaped pipe section and the pipeline beam unit, only the displacement of the main node is calculated,
  • the grid node displacement forming module 42 is electrically connected to the total node displacement calculating module 41, and is used to calculate the displacement of each slave node corresponding to the master node according to the displacement of the master node, and is also used to aggregate the displacement of each slave node and other grid node displacements of the grid model of the special-shaped pipe section obtained in the finite element calculation to form the grid node displacement of the grid model of the special-shaped pipe section.
  • the beam unit internal force calculation module 44 is electrically connected to the total node displacement calculation module 41 and is used to calculate the node internal force of the pipeline beam unit according to the node displacement of the pipeline beam unit.
  • the shell unit stress calculation module 43 is electrically connected to the grid node displacement forming module 42, and is used to calculate the internal force of each shell unit according to the grid node displacement of the grid model of the special-shaped pipe section to obtain the stress of the special-shaped pipe.
  • the finite element calculation module 4 further includes a judgment module 45, which is electrically connected between the interface module 7 and the grid node displacement forming module 42, and is used to judge whether the working condition is a non-temperature working condition or a temperature working condition.
  • the grid node displacement forming module is triggered to calculate the displacement of each slave node corresponding to the master node according to the displacement of the master node using the following formula:
  • d is the displacement of the master node
  • d′ is the displacement of the slave node corresponding to the master node
  • a is the conversion matrix for converting the master node displacement to the slave node displacement
  • the grid node displacement forming module is triggered to calculate the displacement of each slave node corresponding to the master node according to the displacement of the master node using the following formula:
  • alf is the thermal expansion coefficient of the pipe material.
  • the mesh node displacement forming module 42 includes a shell slave node displacement calculation module 421 and a shell node displacement summary module 422.
  • the shell slave node displacement calculation module 421 is electrically connected to the total node displacement calculation module 41, and is used to calculate the displacement of each slave node corresponding to the master node according to the displacement of the master node.
  • the shell node displacement summary module 422 is electrically connected to the shell slave node displacement calculation module 421 and the total node displacement calculation module 41, respectively, and is used to summarize the displacement of each slave node and the other grid node displacements of the grid model of the special-shaped pipe section obtained in the finite element calculation to form the grid node displacement of the grid model of the special-shaped pipe section.
  • Embodiment 4 is a diagrammatic representation of Embodiment 4:
  • This embodiment provides a pipeline mechanics analysis device with a special-shaped pipe section, including the pipeline mechanics calculation device with a special-shaped pipe section of embodiment 3, and a stress assessment module.
  • the stress assessment module is electrically connected to the finite element calculation module and the stress calculation module of the pipeline mechanics calculation device with special-shaped pipe sections, and is used to perform stress assessment on the pipeline with special-shaped pipe sections according to the stress of each shell unit and the stress of each pipeline beam unit.
  • the questions established using the technology of the present invention can very conveniently generate calculations of shell units of various equipment and components, as shown in FIG10 , and these calculations are completed at one time.
  • the total weight calculated by this shell unit model is exactly the same as the mass of the pipe beam. Moreover, the calculation of each working condition here is completed at one time, and the stress assessment of the pipe beam unit and shell unit under each working condition can be completed automatically at one time.

Landscapes

  • Engineering & Computer Science (AREA)
  • Theoretical Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • General Engineering & Computer Science (AREA)
  • General Physics & Mathematics (AREA)
  • Computer Hardware Design (AREA)
  • Evolutionary Computation (AREA)
  • Geometry (AREA)
  • Human Computer Interaction (AREA)
  • Management, Administration, Business Operations System, And Electronic Commerce (AREA)

Abstract

一种具有异型管段的管道力学计算方法及装置,方法包括:根据管道中各部件的参数信息,生成由多个管道梁单元连接组成的管道梁模型,获取需详细分析的异型管段的网格划分信息,以及其在管道梁模型中的节点信息,生成由多个壳单元拼接形成的异型管段的网格模型,采用所述异型管段的网格模型替换管道梁模型中对应位置的管道梁单元,以形成混合模型,计算异型管段的材料密度,并替换异型管段参数信息中的线密度,形成更新后的异型管段的参数信息,对混合模型进行有限元计算,得到混合模型的各节点的位移,进而分别计算管道梁单元和目标壳部件的应力。该方法能够一次完成管道和异型管壳部件的计算和评定,大大提高了管道设计效率及准确性。

Description

一种具有异型管段的管道力学计算方法及装置、分析方法及装置
本公开要求申请日为2022年11月23日、申请号为CN 202211472307.2、名称为“一种具有异型管段的管道力学计算方法及装置”的中国专利申请的优先权,该申请的全部内容通过引用结合在本公开中。
技术领域
本发明涉及管道设计技术领域,具体涉及一种具有异型管段的管道力学计算方法及装置、分析方法及装置。
背景技术
目前的管道计算软件,都是采用一维的管道梁单元做模型计算的,包括直管梁单元和曲管梁单元,它们都是线单元。且管道和设备计算通常都是分开进行的,先做管道计算,得到管道对设备的推力后,再做载荷组合计算,然后再用组合后载荷对设备作应力分析计算和评定。也有些程序可以用壳单元进行特殊部件的计算。但建立壳单元部件的方法比较复杂,有的需要一个节点一个节点的输入节点坐标,再对每一个壳单元做详细描述。有的需要采用单独的建模模块创建壳单元模型,然后主程序把此壳单元部件做成一个刚度矩阵,带入管道模型中进行计算,该计算结果中,壳单元模型只能得到两端连接点的位移和内力。得到管道解后,再将部件上的力加到设备上对壳单元部件单独做计算。可见现有的管道计算软件不能方便的建立起壳单元部件是一个最主要的技术问题。
将壳单元部件模型直接放到管道题目中的方法,在原理上没有问题。目前通用的有限元程序都可以做到,但问题是工作效率极低,这里包括:建模效率,管道与壳部件的连接技术方法,过程中的规范处理要 求,评定时的规范要求的实施,这些问题是通用有限元软件不能满足工程设计计算分析应用需求的原因。这里牵扯的技术有:用户交互,或称管道描述方法定义,管道程序计算,包括标准限制的支撑要求,规范要求的计算方法和管道载荷的对应,管道部件尤其是异型管的模型化方法,管道单元与壳单元的对应关系等。
发明内容
本发明所要解决的技术问题是针对现有技术中存在的上述不足,提供一种能够一次完成管道和异型管壳部件的计算和评定,从而大大提高管道设计工作效率的管道力学计算方法及装置。
解决本发明技术问题所采用的技术方案是:
本发明提供一种具有异型管段的管道力学计算方法,包括:
根据管道中各部件的参数信息,生成由多个管道梁单元连接组成的管道梁模型,以及各管道梁单元的节点信息,其中,部件与管道梁单元一一对应,
获取需详细分析的异型管段的网格划分信息,以及其在管道梁模型中的节点信息,生成由多个壳单元拼接形成的异型管段的网格模型,以及所述网格模型中的网格节点信息,
采用所述异型管段的网格模型替换管道梁模型中对应位置的管道梁单元,以形成混合模型,
计算异型管段的材料密度,并替换异型管段参数信息中的线密度,形成更新后的异型管段的参数信息,
根据待计算的管道的工况信息,以及管道中各部件的参数信息,对所述混合模型进行有限元计算,得到混合模型的各节点的位移,根据管道梁单元的节点位移,计算管道梁单元的节点内力,根据异型管段的网格模型的网格节点位移,计算各壳单元的应力,
根据管道梁单元的节点内力,计算管道梁单元的应力。
可选地,所述异型管段包括弯管,
计算所述弯管的材料密度,具体包括:
根据弯管的线密度w a,确定弯管的理论材料密度w a′,其计算公式为:w a′=w a/g a/t a,其中,对弯管环向分段后,端面圆形成N段圆弧,g a为圆弧的长度,g a=πD a/N,t a为弯管的壁厚,D a为弯管的管径,
根据弯管的环向划分段数,计算弯管的环向折算密度系数fac a,其计算公式为:fac a=g a/g a′,其中,g a′为对弯管环向分段后,圆弧对应的折线段的长度,g a′=2D a×sin(180/N),
根据弯管的轴向划分段数,计算弯管的轴向折算密度系数fac a′,对弯管轴向分段后,弯管形成n个弯管分段,设弯管分段始末端面中心点连线的长度为L,其中,L=2R×sin(β/2n),R为弯管的弯曲半径,β为弯管的转弯角度,弯管分段的轴向中心点所在的断面椭圆周长为l,其中,断面椭圆的长轴长度a=r,断面椭圆的短轴长度b=r×cos(β/2n),轴向折算密度系数fac a′的计算公式为:fac a′=s/(n×L×l),其中,s为弯管的表面积,
再根据下式计算弯管的材料密度w a″:
w a″=w a′×fac a×fac a′。
可选地,所述异型管段包括三通管,
计算所述三通管的材料密度,具体包括:
根据主管或支管的线密度w b,确定主管或支管的理论材料密度w b′,其计算公式为:w b′=w b/g b/t b,其中,对主管或支管环向分段后,端面圆形成多段圆弧,g b为圆弧的长度,t b为主管或支管的壁厚,
根据主管或支管模型替换前后的面积,计算主管或支管的面积折算系数fac b,其计算公式为:fac b=A/A′,其中,
A为主管或支管模型替换前,不考虑面积的缺失或多出,所计算得到的面积,其中,A=π×D b×L b,D为主管或支管的管径,L b为主管或支管的端部圆中心至三通管的三管中心轴线相交点的连线长度,
A′为主管或支管模型替换后,考虑面积的缺失或多出,所计算得到的面积,所述A′具体为根据所述网格模型中主管或支管的网格节点信息,计算得到的主管或支管的壳单元面积之和,
再根据下式计算主管或支管的材料密度:
w b″=w b′×fac b
可选地,所述异型管段包括锥管,
计算所述锥管的材料密度,具体包括:
计算锥管的重量W=w c×L c
根据锥管的平均壁厚,其计算公式为t c=(T+t)/2,其中,T为锥管大端壁厚,t为锥管小端壁厚,
计算锥管网格化后的表面积,其计算公式为
Figure PCTCN2022135739-appb-000001
Figure PCTCN2022135739-appb-000002
其中,R c为锥管大端半径,r c为锥管小端半径,L c为锥管长度,N c为锥管环向分段数,
根据锥管的平均壁厚,以及锥管网格化后的表面积,计算锥管的体积V=A c×t c
再根据下式计算锥管的材料密度w c′:
w c′=W/V。
可选地,设异型管段的网格模型与管道梁单元连接处的管道梁单元的节点为主节点,设异型管段的网格模型与管道梁单元连接处与所述主节点对应的异型管段的网格模型的各节点为从节点,
对所述混合模型进行有限元计算,得到混合模型的各节点的位移,包括:在异型管段的网格模型与管道梁单元连接处,只计算主节点的位移,
所述根据异型管段的网格模型的网格节点位移,计算各壳单元的应力,具体包括:
根据主节点的位移,计算与所述主节点对应的各从节点的位移,
所述各从节点的位移,以及有限元计算中得到的异型管段的网格模型的其他网格节点位移,构成异型管段的网格模型的网格节点位移,
根据所述异型管段的网格模型的网格节点位移,计算各壳单元的应力。
可选地,在根据主节点的位移,计算与所述主节点对应的各从节点的位移之前,还包括:判断工况为非温度工况还是温度工况,
若判断工况为非温度工况,根据主节点的位移,采用下式计算与所述主节点对应的各从节点的位移:
d′=d×a
其中,d为主节点的位移,d′为所述主节点对应的从节点的位移,a为将主节点位移转换到从节点位移的转换矩阵;
若判断工况为温度工况,根据主节点的位移,采用下式计算与所述主节点对应的各从节点的位移:
d′=d×(a×(1+alf))
其中,alf为管道材料的热膨胀系数。
本发明还提供一种具有异型管段的管道力学分析方法,包括:
采用上述的具有异型管段的管道力学计算方法计算得到各壳单元的应力和各管道梁单元的应力,
根据各壳单元的应力和各管道梁单元的应力,对所述具有异型管段的管道进行应力评定。
本发明还提供一种具有异型管段的管道力学计算装置,包括:
管道梁生成模块,用于根据管道中各部件的参数信息,生成由多个管道梁单元连接组成的管道梁模型,以及各管道梁单元的节点信息,其中,部件与管道梁单元一一对应,
壳生成模块,用于获取需详细分析的异型管段的网格划分信息,以及其在管道梁模型中的节点信息,生成由多个壳单元拼接形成的异型 管段的网格模型,以及所述网格模型中的网格节点信息,
替换模块,用于采用所述异型管段的网格模型替换管道梁模型中对应位置的管道梁单元,以形成混合模型,
壳参数形成模块,用于计算异型管段的材料密度,并替换异型管段参数信息中的线密度,形成更新后的异型管段的参数信息,
有限元计算模块,用于根据待计算的管道的工况信息,以及管道中各部件的参数信息,对所述混合模型进行有限元计算,得到混合模型的各节点的位移,根据管道梁单元的节点位移,计算管道梁单元的节点内力,根据异型管段的网格模型的网格节点位移,计算各壳单元的应力,
应力计算模块,根据管道梁单元的节点内力,计算管道梁单元的应力。
可选地,还包括接口模块,用于接收待计算管道的工况信息和各部件的参数信息并传输至管道梁生成模块和有限元计算模块,且还将异型管段的参数信息分别传输至壳生成模块和壳参数形成模块;
还用于接收异型管段的编号信息和网格划分信息并传输至壳生成模块,还将异型管段的编号信息传输至壳参数形成模块。
可选地,所述异型管段包括弯管,
所述壳参数形成模块计算弯管的材料密度,具体包括:
根据弯管的线密度w a,确定弯管的理论材料密度w a′,其计算公式为:w a′=w a/g a/t a,其中,对弯管环向分段后,端面圆形成N段圆弧,g a为圆弧的长度,g a=πD a/N,t a为弯管的壁厚,D a为弯管的管径,
根据弯管的环向划分段数,计算弯管的环向折算密度系数fac a,其计算公式为:fac a=g a/g a′,其中,g a′为对弯管环向分段后,圆弧对应的折线段的长度,g a′=2D a×sin(180/N),
根据弯管的轴向划分段数,计算弯管的轴向折算密度系数fac a′,对弯管轴向分段后,弯管形成n个弯管分段,设弯管分段始末端面中心点连线的长度为L,其中,L=2R×sin(β/2n),R为弯管的弯曲半径, β为弯管的转弯角度,弯管分段的轴向中心点所在的断面椭圆周长为l,其中,断面椭圆的长轴长度a=r,断面椭圆的短轴长度b=r×cos(β/2n),轴向折算密度系数fac a′的计算公式为:fac a′=s/(n×L×l),其中,s为弯管的表面积,
再根据下式计算弯管的材料密度w a″:
w a″=w a′×fac a×fac a′。
可选地,所述异型管段包括三通管,
所述壳参数形成模块还与壳生成模块电连接,其计算三通管的材料密度,具体包括:
根据主管或支管的线密度w b,确定主管或支管的理论材料密度w b′,其计算公式为:w b′=w b/g b/t b,其中,对主管或支管环向分段后,端面圆形成多段圆弧,g b为圆弧的长度,t b为主管或支管的壁厚,
根据主管或支管模型替换前后的面积,计算主管或支管的面积折算系数fac b,其计算公式为:fac b=A/A′,其中,
A为主管或支管模型替换前,不考虑面积的缺失或多出,所计算得到的面积,其中,A=π×D b×L b,D为主管或支管的管径,L b为主管或支管的端部圆中心至三通管的三管中心轴线相交点的连线长度,
A′为主管或支管模型替换后,考虑面积的缺失或多出,所计算得到的面积,所述A′具体为根据所述网格模型中主管或支管的网格节点信息,计算得到的主管或支管的壳单元面积之和,
再根据下式计算主管或支管的材料密度:
w b″=w b′×fac b
可选地,所述异型管段包括锥管,
所述壳参数形成模块还与壳生成模块电连接,其计算锥管的材料密度,具体包括:
计算锥管的重量W=w c×L c
根据锥管的平均壁厚,其计算公式为t c=(T+t)/2,其中,T为锥管 大端壁厚,t为锥管小端壁厚,
计算锥管网格化后的表面积,其计算公式为
Figure PCTCN2022135739-appb-000003
Figure PCTCN2022135739-appb-000004
其中,R c为锥管大端半径,r c为锥管小端半径,L c为锥管长度,N c为锥管环向分段数,
根据锥管的平均壁厚,以及锥管网格化后的表面积,计算锥管的体积V=A c×t c
再根据下式计算锥管的材料密度w c′:
w c′=W/V。
可选地,所述壳参数形成模块包括材料密度计算模块和参数更新模块,
所述材料密度计算模块与接口模块电连接,用于根据异型管段的参数信息,计算异型管段的材料密度,
所述参数更新模块与材料密度计算模块电连接,用于采用所述异型管段的材料密度替换替换异型管段参数信息中的线密度,形成更新后的异型管段的参数信息。
可选地,设异型管段的网格模型与管道梁单元连接处的管道梁单元的节点为主节点,设异型管段的网格模型与管道梁单元连接处与所述主节点对应的异型管段的网格模型的各节点为从节点,
所述有限元计算模块包括总节点位移计算模块、网格节点位移形成模块、梁单元内力计算模块和壳单元应力计算模块,
所述总节点位移计算模块用于对所述混合模型进行有限元计算,得到混合模型的各节点的位移,其包括:在异型管段的网格模型与管道梁单元连接处,只计算主节点的位移,
所述网格节点位移形成模块与总节点位移计算模块电连接,用于根据主节点的位移,计算与所述主节点对应的各从节点的位移,还用于 将所述各从节点的位移,以及有限元计算中得到的异型管段的网格模型的其他网格节点位移汇总,构成异型管段的网格模型的网格节点位移,
所述梁单元内力计算模块与总节点位移计算模块电连接,用于根据管道梁单元的节点位移,计算管道梁单元的节点内力,
所述壳单元应力计算模块与网格节点位移形成模块电连接,用于根据所述异型管段的网格模型的网格节点位移,计算各壳单元的应力。
可选地,所述有限元计算模块还包括判断模块,所述判断模块电连接于接口模块和网格节点位移形成模块之间,用于判断工况为非温度工况还是温度工况,
若判断工况为非温度工况,则触发网格节点位移形成模块根据主节点的位移,采用下式计算与所述主节点对应的各从节点的位移:
d′=d×a
其中,d为主节点的位移,d′为所述主节点对应的从节点的位移,a为将主节点位移转换到从节点位移的转换矩阵;
若判断工况为温度工况,则触发网格节点位移形成模块根据主节点的位移,采用下式计算与所述主节点对应的各从节点的位移:
d′=d×(a×(1+alf))
其中,alf为管道材料的热膨胀系数。
可选地,所述网格节点位移形成模块包括壳从节点位移计算模块和壳节点位移汇总模块,
壳从节点位移计算模块与总节点位移计算模块电连接,用于根据主节点的位移,计算与所述主节点对应的各从节点的位移,壳节点位移汇总模块分别与壳从节点位移计算模块和总节点位移计算模块电连接,用于将所述各从节点的位移,以及有限元计算中得到的异型管段的网格模型的其他网格节点位移汇总,构成异型管段的网格模型的网格节点位移。
本发明还提供一种具有异型管段的管道力学分析装置,包括上述 的具有异型管段的管道力学计算装置,以及应力评定模块,
所述应力评定模块分别与具有异型管段的管道力学计算装置的有限元计算模块和应力计算模块电连接,用于根据各壳单元的应力和各管道梁单元的应力,对所述具有异型管段的管道进行应力评定。
本发明中,对于需要进行详细力学分析的异型管部件,通过生成有限元网格模型(网格划分后,每相邻四个节点构成一个壳单元),代替管道梁模型中对应位置的管道梁单元,在确定异型管段材料密度后,对形成的混合模型进行有限元计算求解,得到混合模型中各节点的位移,根据混合模型中梁单元的节点位移,即可计算管道梁单元的节点内力,继而再计算管道梁单元的应力,根据异型管段网格模型的网格节点位移,即可计算各壳单元的内力(即应力)。从而本发明一次性完成了管道梁单元和异型管壳部件的计算和评定,中间不存在不必要的保守性组合处理过程,大大提高了管道设计的工作效率。并且与采用一维管道梁单元做模型计算的方法相比,本发明的计算准确性大幅提高。
附图说明
图1为本发明实施例1提供的具有异型管段的管道力学计算方法的流程图;
图2为管道的截面网格化分的示意图;
图3为弯管轴向分段及网格化的示意图;
图4为图3中的a-a截面图;
图5为三通管的结构示意图;
图6为三通主管实际面积计算的示意图;
图7为锥管网格化示意图;
图8为管梁单元和壳单元连接面的主从节点示意图;
图9为本发明实施例2提供的具有异型管段的管道力学计算装置 的框图;
图10为本发明的管道程序建立的带异型管壳部件的管道模型图;
图11为本发明的管道程序中管道梁题目的语句说明图。
具体实施方式
为使本领域技术人员更好地理解本发明的技术方案,下面结合附图和实施例对本发明作进一步详细描述。
实施例1
如图1所示,本实施例提供一种具有异型管段的管道力学计算方法,包括:
根据管道中各部件的参数信息,生成由多个管道梁单元连接组成的管道梁模型,以及各管道梁单元的节点信息,其中,部件与管道梁单元一一对应,
获取需详细分析的异型管段的网格划分信息,以及其在管道梁模型中的节点信息,生成由多个壳单元拼接形成的异型管段的网格模型,以及所述网格模型中的网格节点信息,
采用所述异型管段的网格模型替换管道梁模型中对应位置的管道梁单元,以形成混合模型,
计算异型管段的材料密度,并替换异型管段参数信息中的线密度,形成更新后的异型管段的参数信息,
根据待计算的管道的工况信息,以及管道中各部件的参数信息,对所述混合模型进行有限元计算,得到混合模型的各节点的位移,根据管道梁单元的节点位移,计算管道梁单元的节点内力,根据异型管段的网格模型的网格节点位移,计算各壳单元的应力,
根据管道梁单元的节点内力,计算管道梁单元的应力。
在工程设计过程中,无论是核电站、火电站、石化工项目中通常 都有大量的管道,对管道的分析计算占工厂设计工作的很大一部分。需要采用计算机软件对管道的布置做力学分析计算,证明其设计的合理性。本发明技术是管道计算的计算机程序算法中的多个过程之一。以往的管道程序多数都是用一维的梁单元模拟管道的,包括直管梁单元和异型管(包括弯管、三通管、锥管等)梁单元,它们都是线单元。本发明技术是在把异型管梁单元转换为三维的壳单元模型时,为满足管道梁和壳单元部件的混合模型在有限元计算的要求,需要采用的技术手段。
对于需要进行详细力学分析计算的异型管部件,通过生成有限元网格模型(网格划分后,每相邻四个节点构成一个壳单元),代替管道梁模型中对应位置的管道梁单元,在确定异型管段材料密度后,对形成的混合模型进行有限元计算求解,得到混合模型中各节点的位移,根据混合模型中梁单元的节点位移,即可计算管道梁单元的节点内力,继而再计算管道梁单元的应力,根据异型管段网格模型的网格节点位移,即可计算各壳单元的内力(即应力)。从而本发明一次性完成了管道梁单元和异型管壳部件的计算和评定,中间不存在不必要的保守性组合处理过程,大大提高了管道设计的工作效率。并且与采用一维管道梁单元做模型计算的方法相比,本发明的计算准确性大幅提高。
针对前述目前管道程序中普遍存在的弱点,本发明提出了上述的管道力学计算方法,可以通过在原有管道计算题目数据中加进简单输入要求,由管道程序自动的将异性管段如一维曲梁单元弯头(注意:虽然是一维线单元,它实际描述的是一个已知弯曲半径的有直径管道的部分圆环)转换为三维壳单元模型,原来的曲管单元只有三个节点(始点、末点和参考点),转换后,可能成为几百,几千个节点,每相邻四个节点首尾依次相连构成一个壳单元,多个壳单元拼接形成三维壳单元模型。
这里的由一个光滑的圆环管道,离散化分为有限个三维壳单元过程,是有限元程序的前处理网格划分技术,这是本技术领域的公知技术。梁单元的端部是一个节点,壳单元端部是多个节点构成的一个面,把一 个点和由多个点构成的一个面关联的技术也是本领域的公知技术。本发明将这些技术集成至管道计算程序的建模模块中,以此方法自动建立的模型,可以在管道计算过程中,同时自动地把管道梁单元和壳单元计算完成。实现此功能,程序的结构需要满足多种单元的功能要求,而且这里要满足管道和壳单元计算的各种要求。包括管梁处理以及它和壳部件的连接方法,还包括对管道中部件转换为壳单元时做质量密度换算的精确方法。
在由管道转换成壳单元时需要确定目标壳部件的材料密度。对于管道模型,市场上的所有程序都需要给定管道的线密度,其中包括管道的材料重量,一般为钢材,工作介质重量,保温材料重量。而对于壳单元的计算,有所不同,需要给定的是目标壳部件的材料密度,在做重量计算时,程序通常是由壳的面积乘以厚度再乘以材料密度得到壳单元的重量。
在由管道提供的线重量计算目标壳部件的材料密度时,一般的算法是将单位长度的线密度除以管道周长和管道厚度作为目标壳部件的材料密度,这样做的问题是结果不够准确,尤其是当划分段数不大时,会产生较大误差。申请人一开始提出了以下处理方法:
管道断面如图2所示:图中的圆是管道中面示意图,这里忽略了管道的壁厚,中面半径为R。将此管道在圆周方向上分为六段时的图形如下。其中长度L是壳单元的一个边长,也就是分割后的折线长度。
一圆管如在圆周方向把它划分为六段,360/6=60,α=60度一段。由图中可以看出,实际管道中的一段折线长度g′要小于对应的弧线长度g,弧长g=2×r×π×60/360=r×π/3。折线长g′=r×sin(30)×2=r。弧长与折线长之比为π/3=1.047198。推广到任意圆周分段数后的由给定的管道线密度w换算直管道材料密度算法是:
对圆弧段其折算密度:w′=w/g/t,这里的w为给定管道线密度,t是管道壁厚;
圆弧段弧长为:g=D×π/N,D是管道直径,N是分段数,π=3.1415926;
对应的折线段长度:g′=(D/2×sin(2×π/N/2))×2=D/sin(π/N);
根据g,g′的关系:fac=g/g′=D×π/N/(D/sin(π/N))=π/N/sin(π/N);
壳单元密度:w″=w′×fac。
申请人的前期研究表明,这样处理的直管壳单元密度,无论周向把管道划分为多少段,计算得到的管重都是正确的。然而对于异型管,如弯头、三通、锥管等,此处理方法存在缺陷,转换完模型的重量和开始时的管道粱模型重量有所改变。经分析研判,造成弯头壳单元模型重量差别的原因是曲管单元的重量等于管道的线重量乘以弯头弧线长度。而按照上述处理方法计算得到的壳单元密度,在考虑壳单元面积后得到的壳单元弯头重量小于弯头的实际重量。造成此误差的原因是将弯管离散化为小矩形平面单元时,除了周向(环向)曲线变为折线外,轴线方向也要由曲线变为折线,而对于弯头,这时将弯头管道的弯曲轨迹由光滑曲线变为折线时,管道的截面也随之改变了,在做壳单元密度换算时,必须考虑这个因素的影响。而对于锥管(也称渐缩管)、三通等部件也需要做适应性修改,不能直接采用上述处理方法。
本实施例中,所述异型管段包括弯管,
所述弯管的参数信息包括:
所述弯管在管道梁模型中的节点信息包括始末节点和参考节点的节点号和坐标值,
计算所述弯管的材料密度,具体包括:
根据弯管的线密度w a,确定弯管的理论材料密度w a′,其计算公式为:w a′=w a/g a/t a,其中,对弯管环向分段后,端面圆形成N段圆弧,g a为圆弧的长度,g a=πD a/N,t a为弯管的壁厚,D a为弯管的管径,
根据弯管的环向划分段数,计算弯管的环向折算密度系数fac a,其 计算公式为:fac a=g a/g a′,其中,g a′为对弯管环向分段后,圆弧对应的折线段的长度,g a′=2D a×sin(180/N),
根据弯管的轴向划分段数,计算弯管的轴向折算密度系数fac a′,对弯管轴向分段后,弯管形成n个弯管分段,设弯管分段始末端面中心点连线的长度为L,其中,L=2R×sin(β/2n),R为弯管的弯曲半径,β为弯管的转弯角度,弯管分段的轴向中心点所在的断面椭圆周长为l,其中,断面椭圆的长轴长度a=r,断面椭圆的短轴长度b=r×cos(β/2n),轴向折算密度系数fac a′的计算公式为:fac a′=s/(n×L×l),其中,s为弯管的表面积,
再根据下式计算弯管的材料密度w a″:
w a″=w a′×fac a×fac a′。
上述弯管的材料密度w a″计算分析过程如下:
在由弯曲管道转换成壳单元时需要确定壳单元的材料密度。对于管道模型,市场上的所有程序都给定了管道的线密度,其中包括管道的材料重量,一般为钢材,工作介质重量,保温材料的重量。而对于壳单元,有所不同,需要给定的是壳单元的材料密度,在做重量计算时,程序通常是由壳的面积乘以厚度再乘以材料密度得到一个壳单元的重量。在由管道提供的线重量计算壳单元的材料密度时,一般的算法是将单位长度的线密度除以管道周长和管道厚度作为壳单元的材料密度,这样做的结果不够准确,尤其是当划分段数不大时,会产生较大误差,对于弯曲管道,问题更加复杂。假如弯曲管道如图3所示:
若将这个旋转了180度的弯曲管道,分为三段处理,如图3,首先对于环向的分段(假设分为六段,图中没有示出),在图2的分析中已经考虑,那是管道环向分段的情况。这里只分析轴线方向分段的情况。假设这个180度的弯头,把它分三段做壳单元模型。程序在网格划分时,环向的分段假设要分为6段,只在0-0和1-1两个断面求得节点坐标,0-0和1-1断面是圆形的,而对于a-a断面就不再是圆形截面了,它变 成了椭圆,如图4所示。椭圆的长半轴就是管道的半径r,而短半轴长度和轴向分段数有关。
L=2R×sin(β/2n),a=r,b=r×cos(β/2n)。
图3中,每段轴向折线长度L:2R×sin(60/2)=R,其对应的弧长=R×π/3。
Figure PCTCN2022135739-appb-000005
因而弯管的材料密度还应有一个系数fac a′=光滑面积/折线面积=光滑面积/(椭圆周长×折线总长)。
椭圆的周长没有简单的初等数学表达式描述。可以用精度较高的如下表达式,求得弯头a-a处的截面椭圆周长:
椭圆周长
Figure PCTCN2022135739-appb-000006
其中:q a+b,
Figure PCTCN2022135739-appb-000007
综合起来,第一步:如上述直管的分析得出壳单元材料密度:w a″=w a′×fac a
这是上述对直管壳单元密度的分析结果。
第二步,再加上前边关于管道断面变成椭圆后的处理,弯头壳单元的密度:w a″=w a′×fac a×fac a′:
fac a′=弯头光滑面积s/弯头折线面积=光滑面积s/(椭圆周长l×折线总长n×L)==s/(n×L×l)。
本实施例中,所述异型管段包括三通管,
所述三通管的参数信息包括:
所述三通管在管道梁模型中的节点信息包括支管和两根主管相交的节点以及各自的端部节点的节点号和坐标值,
计算所述异型管段的材料密度,具体包括:
根据主管或支管的线密度w b,确定主管或支管的理论材料密度w b′,其计算公式为:w b′=w b/g b/t b,其中,对主管或支管环向分段后,端面圆形成多段圆弧,g b为圆弧的长度,t b为主管或支管的壁厚,
根据主管或支管模型替换前后的面积,计算主管或支管的面积折算系数fac b,其计算公式为:fac b=A/A′,其中,
A为主管或支管模型替换前,不考虑面积的缺失或多出,所计算得到的面积,其中,A=π×D b×L b,D为主管或支管的管径,L b为主管或支管的端部圆中心至三通管的三管中心轴线相交点的连线长度,
A′为主管或支管模型替换后,考虑面积的缺失或多出,所计算得到的面积,所述A′具体为根据所述网格模型中主管或支管的网格节点信息,计算得到的主管或支管的壳单元面积之和,
再根据下式计算主管或支管的材料密度:
w b″=w b′×fac b
对于三通,如图5所示,由于做成壳单元模型后,支管和主管连接处缺少了材料,采用前述两种(直管和弯头)计算方法都不能正确的描述管道三通的重量。必须根据模型制作的条件,考虑壳单元的分段数计算壳单元密度。这里有两个问题,一是在离散化时,主、支管连接处的曲线变成了直线,二是主管和支管的分段数可能不同,在做面积计算时都要考虑到。
对于主管需要考虑支管的分段数,如图6所示,为便于说明,图中标出主管环向分了6(图中只示出三段),后边计算主管面积时应考虑它们的影响。主管与支管连接处缺少了材料,计算面积时还需考虑这个影响,整个支管按12段划分,图中需考虑的只有6段(另6段与另一主管相交)。在计算主管面积时,可以把管道分成两部分,长度为L 1的部分和长度为l 1的部分,用支管直径确定分界点,l 1=d/2。L部分的面积按照普通直管进行计算(环向六边形周长×L 1),l 1部分在r以下部分也按普通直管进行计算((环向六边形周长/2)×l 1)。r以下部分要对每个壳单元的顶点逐点计算坐标,以求得每个梯形的平均高度和它的面积。还可以直接调用主管各节点坐标值,计算得到主管的各壳单元面积之和。
在任何以往管道程序的题目中三通都是采用与直管相同的方法描述的管道线密度,对题目的三通重量的计算比较简单,长度乘以线重量。而在做三通壳单元密度计算时,将根据按管道粱单元计算得到的面积A,A=D×π×(L 1+l 1),考虑本次的主、支管壳单元的划分个数后计算的实际总面积A′,则壳单元的材料密度w b″=w b′×A/A′。A′的算法按前述两种方法计算得到。
对于支管而言,支管与主管连接处增加了材料,计算时也需考虑这个影响,计算方法参照主管的上述两种计算方法,在此不再赘述。
本实施例中,所述异型管段包括锥管,
所述锥管的参数信息包括:
所述锥管在管道梁模型中的节点信息包括始末节点的节点号和坐标值,
计算所述锥管的材料密度,具体包括:
计算锥管的重量W=w c×L c
根据锥管的平均壁厚,其计算公式为t c=(T+t)/2,其中,T为锥管大端壁厚,t为锥管小端壁厚,
计算锥管网格化后的表面积,其计算公式为
Figure PCTCN2022135739-appb-000008
Figure PCTCN2022135739-appb-000009
其中,R c为锥管大端半径,r c为锥管小端半径,L c为锥管长度,N c为锥管环向分段数,
根据锥管的平均壁厚,以及锥管网格化后的表面积,计算锥管的体积V=A c×t c
再根据下式计算锥管的材料密度w c′:
w c′=W/V。
对于锥管(也称渐缩管)原则上看起来和直管的算法一致,实际不然。除了需要按照平均壁厚和平均直径考虑外,计算壳单元的长度时, 其长度并不是用户输入的大小头管道单元的长度,即图7中的L c
如图7所示,该渐缩管的壁厚可按照大头壁厚和小头壁厚的平均值考虑t c=(T+t)/2。在管道程序的输入数据中都会给出本部件的线重量,它的计算重量W等于线重量和部件长度的乘积:W=w c×L c。在转换为壳单元材料密度时,要求的壳单元的总体积V,壳单元密度=W/V。划分为壳单元时,环向的分段数对结果有影响。按照求出每个分段的面积乘以平均壁厚做每一段的体积计算。每个分段的宽度要用平均宽度b计算,分段长度不是L c,也不是两个分段的交线棱长,应该是图中划分断面中间的中线(图中用虚线绘出)长度C。其长度:
Figure PCTCN2022135739-appb-000010
其中,H=R ccos(360/2N),h=r ccos(360/2N),
A=a c×N,a c=b c×C,b=(R c+r c)sin(360/2N),a c为一个分段的面积,N为锥管环向分段数,
所以,对于大小头,已知其重量W,计算得到划分为壳后的大小头体积:V=A c×t c,其材料密度:壳单元密度=W/V。
本实施例中,设异型管段的网格模型与管道梁单元连接处的管道梁单元的节点为主节点,设异型管段的网格模型与管道梁单元连接处与所述主节点对应的异型管段的网格模型的各节点为从节点,
对所述混合模型进行有限元计算,得到混合模型的各节点的位移,包括:在异型管段的网格模型与管道梁单元连接处,只计算主节点的位移,
所述根据异型管段的网格模型的网格节点位移,计算各壳单元的应力,具体包括:
根据主节点的位移,计算与所述主节点对应的各从节点的位移,
所述各从节点的位移,以及有限元计算中得到的异型管段的网格模型的其他网格节点位移,构成异型管段的网格模型的网格节点位移,
根据所述异型管段的网格模型的网格节点位移,计算各壳单元的 应力。
在制作管道模型时,如需对其中一段管道做壳单元部件处理,那么要对和它两端相连管道连接作处理。假设管道任意位置的断面始终是一个平面,这个平面是刚性的,这是按梁单元计算管道题目的基本假设。所以一维管道的端点,这里只有一个节点的位置(设为节点n),和与它连接的是改成了壳单元部件,这里没有节点,但在此位置的沿管道外径上有一圈节点,而且这一圈节点并不独立,它们的位移完全是由节点n确定的。例如,图8展示了管梁和壳单元连接部位的情况,8和9节点构成了管道梁单元,这是一个一维的线单元。21到26是壳单元边界上的一圈节点,这些节点的位移解不在有限元模型结构方程位移未知数中,它是由节点9的位移间接得到的。通常的求解过程一般都到此为止。但对于温度载荷此结果不够完整,缺少了刚性面热胀的效果。可以在计算从属节点的位移时,考虑热胀作用的影响,每个从属节点都受到热胀影响对应的长度R有所改变。
本实施例中,在根据主节点的位移,计算与所述主节点对应的各从节点的位移之前,还包括:判断工况为非温度工况还是温度工况,
若判断工况为非温度工况,根据主节点的位移,采用下式计算与所述主节点对应的各从节点的位移:
d′=d×a
其中,d为主节点的位移,d′为所述主节点对应的从节点的位移,a为将主节点位移转换到从节点位移的转换矩阵;
若判断工况为温度工况,根据主节点的位移,采用下式计算与所述主节点对应的各从节点的位移:
d′=d×(a×(1+alf))
其中,alf为管道材料的热膨胀系数。
上述提到的主节点和其从节点构成了一个刚性面,因为这个刚性面不会变形,对一般载荷解这是正确的,但对于温度载荷,会产生问题。 对于管道梁模型,程序计算时,只考虑沿轴线方向的热膨胀,无法求得管道环向的热胀,而对于壳单元部件,施加温度载荷后,壳单元部件部分即可以得到轴线方向的热胀位移,也得到环向的热胀位移。这时在管道梁单元和壳单元部件的连接部就会出现不真实的结果,原因就是这个刚性面。为此需要考虑各个从属节点的热位移影响。不考虑温度效应时,辅助节点的位移等于主节点的位移转移到对应位置上的值:d′=d×a,当需要考虑热胀位移时:d′=d×(a×(1+alf)),alf是材料的热膨胀系数。
目前的管道计算分析软件都无法直接把管道单元和由壳单元描述的管道部件直接放到一起进行分析计算。在管道计算时要分为多种计算工况,如自重工况、温度工况、地震工况。工况不同,运行级别不同评定的标准也不同,这表现在不同的规范公式上。在评定管道时公式中采用了很多系数,直接带到规范公式中的是管道计算得到的管道梁的弯矩,因此,管道梁单元不用直接得到实际应力。而规范评定要求的限值是许用应力,程序要做考虑各种因素(如焊接、如部件类型,加载次数等)对应的计算,这些条件的影响,有些是靠规范给定的系数考虑的,如焊缝系数,它和焊接工艺,连接部件有关。这里存在一些保守因素,用管道梁做计算,这是不可避免的。
对于由壳单元做成的设备,直接用应力进行评定。但它要分为薄膜应力、弯曲应力、薄膜加弯曲应力等,它除了和载荷性质有关外,还和评定位置有关。采用此技术完成的管道计算程序可以非常方便地一次把管道和设备部件计算完成。采用此技术得到的弯头壳单元部件模型的重量和管道梁的重量完全一致,不存在计算差距,这一点对动态分析非常重要,因为题目动态响应(通常采用响应谱法作分析)的结果是和模态振型紧密相关的。而管道题目的模态与模型质量分布密切相关。另一项技术是把异型管梁单元和壳单元密度等效的技术。此技术可以保证由这些部件计算得到的重量与管道题目一致,满足整个题目的计算要求。对于管道评定的要求自然可以满足,而壳单元可以直接得到单元应力, 包括薄膜应力和弯曲应力。采用这两项技术研发的软件的效果是,比通常软件得到的局部结果更加真实,而且可以一次完成管道和设备部件的计算和评定。因为程序的使用方法非常简单,工作效率大大地提高了。同时去掉了设计时的很多保守性,使得管道以及整个工程项目的设计和建造更加经济、高效。
具体的实施要由计算机软件来辅助实现,下面的实施步骤是指采用本发明技术的任何计算机管道设计计算软件的实施过程。
1)首先是常规的管道计算,要根据需要计算的管道题目,生成管道梁单元,这个步骤是管道计算的常规步骤,与本发明无关。但它是本发明技术的基础条件。题目中包括弯头、三通和/或锥管,采用本发明技术要首先规定好如何确定题目中的壳单元部件,要能区分弯头、三通的出入口以及支管。
2)对有将弯管单元要按照壳单元作计算要求时,软件需要确定此单元原来的始末点节点、参考节点号、各节点坐标值,以及本管道单元的直径、弯曲半径、材料、温度、压力等各种信息。下一步是做出有限元求解的模型文件,其中要包括壳单元各种信息,而且要把对应的弯管梁单元取消。
3)对于三通,应该定义是主管还是支管,以及三个部分的单元划分个数要求,三个单元逻辑上必须是连在一起的。在题目中需要取消这三个三通管道梁单元。
4)对第二步骤的始末点坐标间要生成壳单元网格节点坐标和单元号组可以描述这里的壳单元,对壳单元部件类型做标记,区分出直管或曲管单元,还要区分三通的主、支管。
5)对弯管单元分别按照周向分段N和轴向分段n划分单元网格,求得质量修正系数fac a和fac a′。在常规管道描述文件中都会定义管道截面时定义管道的线密度,通常的量纲是单位长度的质量,如每米公斤。而在壳单元计算时需要的是壳单元的材料密度,在这个模型转换过程中, 要保证的原则是:转换完壳单元的部件重量与原来输入的管道单元的重量一致。原来的管道重量是W=管道长度×管道线重量。这个管道的壳模型,其壳面积的总和理论上应该等于本管道单元圆柱侧面积。弯管则需增加质量修正系数fac a和fac a′。
6)对于三通分别按照三通入口、出口和支管求出各部分壳单元的材料密度,w b″=w b′×A/A′。
7)准备好管道计算有限元文件,对每一个计算工况启动有限元计算,程序求解有限元方程组。
8)一起完成管道单元和壳单元的应力计算,并依次分别按照管道和设备规范进行各自的应力评定。
上述第5)步骤,可以得到弯管壳单元的材料密度理论值。但实际上因为每个壳单元都是一个平面,它与管道圆柱面的曲面存在差别。所以可以计算得到对管道表面的理论密度:w a′=w a/(D×π)/t,考虑壳单元因为按平面代替曲面的关系,上述理论密度需要乘以系数fac a,其中fac a=π/N/sin(π/N)。系数fac a是做成壳单元时,因为表面积的减小,需要把管道密度做放大处理。除此之外,还要考虑管道截面变成椭圆的影响,最终,:w a″=w a′×fac a′:
fac a′=弯头光滑面积/弯头折线面积=光滑面积/(椭圆周长×折线总长)。
步骤6)中,求三通的材料密度时,分别按照三通的管道粱面积和壳单元总面积做计算。然后把根据管道线重量换算的材料密度折算为壳单元三通的材料密度w b″=w b′×A/A′,其中A是三通主管粱的圆柱侧面积,A′是划分为壳单元后的实际三通主管的总面积。对于三通支管算法类似。
实施例2:
本实施例提供一种具有异型管段的管道力学分析方法,包括:
采用实施例1的具有异型管段的管道力学计算方法计算得到各壳单元的应力和各管道梁单元的应力,
根据各壳单元的应力和各管道梁单元的应力,对所述具有异型管段的管道进行应力评定。
实施例3:
如图9所示,本发明还提供一种具有异型管段的管道力学计算装置,包括:
管道梁生成模块1,用于根据管道中各部件的参数信息,生成由多个管道梁单元连接组成的管道梁模型,以及各管道梁单元的节点信息,其中,部件与管道梁单元一一对应,
壳生成模块2,用于获取需详细分析的异型管段的网格划分信息,以及其在管道梁模型中的节点信息,生成由多个壳单元拼接形成的异型管段的网格模型,以及所述网格模型中的网格节点信息,
替换模块3,用于采用所述异型管段的网格模型替换管道梁模型中对应位置的管道梁单元,以形成混合模型,
壳参数形成模块6,用于计算异型管段的材料密度,并替换异型管段参数信息中的线密度,形成更新后的异型管段的参数信息,
有限元计算模块4,用于根据待计算的管道的工况信息,以及管道中各部件的参数信息,对所述混合模型进行有限元计算,得到混合模型的各节点的位移,根据管道梁单元的节点位移,计算管道梁单元的节点内力,根据异型管段的网格模型的网格节点位移,计算各壳单元的应力,
应力计算模块5,根据管道梁单元的节点内力,计算管道梁单元的应力。
本实施例中,还包括接口模块7,用于接收待计算管道的工况信息和各部件的参数信息并传输至管道梁生成模块1和有限元计算模块4,且还将异型管段的参数信息分别传输至壳生成模块2和壳参数形成模 块6;
还用于接收异型管段的编号信息和网格划分信息并传输至壳生成模块,还将异型管段的编号信息传输至壳参数形成模块6。
本实施例中,所述异型管段包括弯管,
所述弯管的参数信息包括:
所述弯管在管道梁模型中的节点信息包括始末节点和参考节点的节点号和坐标值,
所述壳参数形成模块6计算弯管的材料密度,具体包括:
根据弯管的线密度w a,确定弯管的理论材料密度w a′,其计算公式为:w a′=w a/g a/t a,其中,对弯管环向分段后,端面圆形成N段圆弧,g a为圆弧的长度,g a=πD a/N,t a为弯管的壁厚,D a为弯管的管径,
根据弯管的环向划分段数,计算弯管的环向折算密度系数fac a,其计算公式为:fac a=g a/g a′,其中,g a′为对弯管环向分段后,圆弧对应的折线段的长度,g a′=2D a×sin(180/N),
根据弯管的轴向划分段数,计算弯管的轴向折算密度系数fac a′,对弯管轴向分段后,弯管形成n个弯管分段,设弯管分段始末端面中心点连线的长度为L,其中,L=2R×sin(β/2n),R为弯管的弯曲半径,β为弯管的转弯角度,弯管分段的轴向中心点所在的断面椭圆周长为l,其中,断面椭圆的长轴长度a=r,断面椭圆的短轴长度b=r×cos(β/2n),轴向折算密度系数fac a′的计算公式为:fac a′=s/(n×L×l),其中,s为弯管的表面积,
再根据下式计算弯管的材料密度w a″:
w a″=w a′×fac a×fac a′。
本实施例中,所述异型管段包括三通管,
所述三通管的参数信息包括:
所述三通管在管道梁模型中的节点信息包括支管和两根主管相交的节点以及各自的端部节点的节点号和坐标值,
所述壳参数形成模块6还与壳生成模块2电连接,其计算三通管的材料密度,具体包括:
根据主管或支管的线密度w b,确定主管或支管的理论材料密度w b′,其计算公式为:w b′=w b/g b/t b,其中,对主管或支管环向分段后,端面圆形成多段圆弧,g b为圆弧的长度,t b为主管或支管的壁厚,
根据主管或支管的环向划分段数,计算主管或支管的环向折算密度系数fac b,其计算公式为:fac b=g b/g b′,其中,g b′为对主管或支管环向分段后,圆弧对应的折线段的长度,
根据主管或支管模型替换前后的面积,计算主管或支管的面积折算系数fac b′,其计算公式为:fac b′=A/A′,其中,
A为主管或支管模型替换前,不考虑面积的缺失或多出,所计算得到的面积,其中,A=π×D b×L b,D为主管或支管的管径,L b为主管或支管的端部圆中心至三通管的三管中心轴线相交点的连线长度,
A′为主管或支管模型替换后,考虑面积的缺失或多出,所计算得到的面积,所述A′具体为根据所述网格模型中主管或支管的网格节点信息,计算得到的主管或支管的壳单元面积之和,
再根据下式计算主管或支管的材料密度:
w b″=w b′×fac b×fac b′。
本实施例中,所述异型管段包括锥管,
所述锥管的参数信息包括:
所述锥管在管道梁模型中的节点信息包括始末节点的节点号和坐标值,
所述壳参数形成模块6计算锥管的材料密度,具体包括:
计算锥管的重量W=w c×L,
根据锥管的平均壁厚,其计算公式为t c=(T+t)/2,其中,T为锥管大端壁厚,t为锥管小端壁厚,
计算锥管网格化后的表面积,其计算公式为
Figure PCTCN2022135739-appb-000011
Figure PCTCN2022135739-appb-000012
其中,R c为锥管大端半径,r c为锥管小端半径,L为锥管长度,N c为锥管环向分段数,
根据锥管的平均壁厚,以及锥管网格化后的表面积,计算锥管的体积V=A c×t c
再根据下式计算锥管的材料密度w c′:
w c′=W/V。
本实施例中,所述壳参数形成模块6包括材料密度计算模块61和参数更新模块62,
所述材料密度计算模块61与接口模块7电连接,用于根据异型管段的参数信息,计算异型管段的材料密度,
所述参数更新模块62与材料密度计算模块61电连接,用于采用所述异型管段的材料密度替换替换异型管段参数信息中的线密度,形成更新后的异型管段的参数信息。
本实施例中,设异型管段的网格模型与管道梁单元连接处的管道梁单元的节点为主节点,设异型管段的网格模型与管道梁单元连接处与所述主节点对应的异型管段的网格模型的各节点为从节点,
所述有限元计算模块4包括总节点位移计算模块41、网格节点位移形成模块42、梁单元内力计算模块44和壳单元应力计算模块43,
所述总节点位移计算模块41用于对所述混合模型进行有限元计算,得到混合模型的各节点的位移,其包括:在异型管段的网格模型与管道梁单元连接处,只计算主节点的位移,
所述网格节点位移形成模块42与总节点位移计算模块41电连接,用于根据主节点的位移,计算与所述主节点对应的各从节点的位移,还用于将所述各从节点的位移,以及有限元计算中得到的异型管段的网格模型的其他网格节点位移汇总,构成异型管段的网格模型的网格节点位 移,
所述梁单元内力计算模块44与总节点位移计算模块41电连接,用于根据管道梁单元的节点位移,计算管道梁单元的节点内力,
所述壳单元应力计算模块43与网格节点位移形成模块42电连接,用于根据所述异型管段的网格模型的网格节点位移,计算各壳单元的内力,以得到异型管的应力。
本实施例中,所述有限元计算模块4还包括判断模块45,所述判断模块45电连接于接口模块7和网格节点位移形成模块42之间,用于判断工况为非温度工况还是温度工况,
若判断工况为非温度工况,则触发网格节点位移形成模块根据主节点的位移,采用下式计算与所述主节点对应的各从节点的位移:
d′=d×a
其中,d为主节点的位移,d′为所述主节点对应的从节点的位移,a为将主节点位移转换到从节点位移的转换矩阵;
若判断工况为温度工况,则触发网格节点位移形成模块根据主节点的位移,采用下式计算与所述主节点对应的各从节点的位移:
d′=d×(a×(1+alf))
其中,alf为管道材料的热膨胀系数。
本实施例中,所述网格节点位移形成模块42包括壳从节点位移计算模块421和壳节点位移汇总模块422,
壳从节点位移计算模块421与总节点位移计算模块41电连接,用于根据主节点的位移,计算与所述主节点对应的各从节点的位移,壳节点位移汇总模块422分别与壳从节点位移计算模块421和总节点位移计算模块41电连接,用于将所述各从节点的位移,以及有限元计算中得到的异型管段的网格模型的其他网格节点位移汇总,构成异型管段的网格模型的网格节点位移。
实施例4:
本实施例提供一种具有异型管段的管道力学分析装置,包括实施例3的具有异型管段的管道力学计算装置,以及应力评定模块,
其中,应力评定模块分别与具有异型管段的管道力学计算装置的有限元计算模块和应力计算模块电连接,用于根据各壳单元的应力和各管道梁单元的应力,对所述具有异型管段的管道进行应力评定。
应用案例
采用本发明技术建立的题目,可以非常方便的生成各种设备和部件的带壳单元的计算,如图10所示,这些计算是一次性完成的。
本带壳单元模型计算得到的总重量与管道梁题目质量完全一致。而且这里的各个工况的计算是一次性完成的,各工况下对管道粱单元和壳单元的应力评定可以一次自动完成。
实现壳单元部件的生成和计算,只需简单的一个语句说明。去掉这个语句,就是管道梁的题目,加上它,题目中就有了壳单元部件。如一个题目中的部分数据如下,下边第二和第五个语句:RSHL,LX=1说明这是个直管,要按壳单元计算。而第八个语句,RSHL,LX=2要求把前边的弯头单元用壳单元做计算。而去掉这三个语句,或加注释符号“*”,这个题目完全就是一个管道梁题目,不用做任何修改,如图11所示。
非常重要的是,现有可以做壳单元的程序中转换为刚度矩阵的壳模型无法做温度和内压的计算,而且静力和动力计算,只用一个刚度矩阵是没法实现的,它的优势是计算速度快。每次整体计算时,除了考虑那个刚度矩阵,不用再做和壳单元有关的工作。但它也存在很大的缺陷,如计算机时间的节省,却给分析人员带来了麻烦,建模型要作分析,评定需分步骤进行,还要做载荷简化等。而本发明很好地解决了上述问题。
可以理解的是,以上实施方式仅仅是为了说明本发明的原理而采用的示例性实施方式,然而本发明并不局限于此。对于本领域内的普通技术人员而言,在不脱离本发明的精神和实质的情况下,可以做出各种变型和改进,这些变型和改进也视为本发明的保护范围。

Claims (17)

  1. 一种具有异型管段的管道力学计算方法,其特征在于,包括:
    根据管道中各部件的参数信息,生成由多个管道梁单元连接组成的管道梁模型,以及各管道梁单元的节点信息,其中,部件与管道梁单元一一对应,
    获取需详细分析的异型管段的网格划分信息,以及其在管道梁模型中的节点信息,生成由多个壳单元拼接形成的异型管段的网格模型,以及所述网格模型中的网格节点信息,
    采用所述异型管段的网格模型替换管道梁模型中对应位置的管道梁单元,以形成混合模型,
    计算异型管段的材料密度,并替换异型管段参数信息中的线密度,形成更新后的异型管段的参数信息,
    根据待计算的管道的工况信息,以及管道中各部件的参数信息,对所述混合模型进行有限元计算,得到混合模型的各节点的位移,根据管道梁单元的节点位移,计算管道梁单元的节点内力,根据异型管段的网格模型的网格节点位移,计算各壳单元的应力,
    根据管道梁单元的节点内力,计算管道梁单元的应力。
  2. 根据权利要求1所述的具有异型管段的管道力学计算方法,其特征在于,
    所述异型管段包括弯管,
    计算所述弯管的材料密度,具体包括:
    根据弯管的线密度w a,确定弯管的理论材料密度w a′,其计算公式为:w a′=w a/g a/t a,其中,对弯管环向分段后,端面圆形成N段圆弧,g a为圆弧的长度,g a=πD a/N,t a为弯管的壁厚,D a为弯管的管径,
    根据弯管的环向划分段数,计算弯管的环向折算密度系数fac a,其计算公式为:fac a=g a/g a′,其中,g a′为对弯管环向分段后,圆弧对应的折线段的长度,g a′=2 D a×sin(180/N),
    根据弯管的轴向划分段数,计算弯管的轴向折算密度系数fac a′,对弯管轴向分段后,弯管形成n个弯管分段,设弯管分段始末端面中心点连线的长度为L,其中,L=2R×sin(β/2n),R为弯管的弯曲半径,β为弯管的转弯角度,弯管分段的轴向中心点所在的断面椭圆周长为l,其中,断面椭圆的长轴长度a=r,断面椭圆的短轴长度b=r×cos(β/2n),轴向折算密度系数fac a′的计算公式为:fac a′=s/(n×L×l),其中,s为弯管的表面积,
    再根据下式计算弯管的材料密度w a″:
    w a″=w a′×fac a×fac a′。
  3. 根据权利要求1所述的具有异型管段的管道力学计算方法,其特征在于,所述异型管段包括三通管,
    所述三通管的参数信息包括:
    计算所述三通管的材料密度,具体包括:
    根据主管或支管的线密度w b,确定主管或支管的理论材料密度w b′,其计算公式为:w b′=w b/g b/t b,其中,对主管或支管环向分段后,端面圆形成多段圆弧,g b为圆弧的长度,t b为主管或支管的壁厚,
    根据主管或支管模型替换前后的面积,计算主管或支管的面积折算系数fac b,其计算公式为:fac b=A/A′,其中,
    A为主管或支管模型替换前,不考虑面积的缺失或多出,所计算得到的面积,其中,A=π×D b×L b,D为主管或支管的管径,L b为主管或支管的端部圆中心至三通管的三管中心轴线相交点的连线长度,
    A′为主管或支管模型替换后,考虑面积的缺失或多出,所计算得到的面积,所述A′具体为根据所述网格模型中主管或支管的网格节点 信息,计算得到的主管或支管的壳单元面积之和,
    再根据下式计算主管或支管的材料密度:
    w b″=w b′×fac b
  4. 根据权利要求1所述的具有异型管段的管道力学计算方法,其特征在于,所述异型管段包括锥管,
    计算所述锥管的材料密度,具体包括:
    计算锥管的重量W=w c×L c
    根据锥管的平均壁厚,其计算公式为t c=(T+t)/2,其中,T为锥管大端壁厚,t为锥管小端壁厚,
    计算锥管网格化后的表面积,其计算公式为
    Figure PCTCN2022135739-appb-100001
    Figure PCTCN2022135739-appb-100002
    其中,R c为锥管大端半径,r c为锥管小端半径,L c为锥管长度,N c为锥管环向分段数,
    根据锥管的平均壁厚,以及锥管网格化后的表面积,计算锥管的体积V=A c×t c
    再根据下式计算锥管的材料密度w c′:
    w c′=W/V。
  5. 根据权利要求1-4任一项所述的具有异型管段的管道力学计算方法,其特征在于,设异型管段的网格模型与管道梁单元连接处的管道梁单元的节点为主节点,设异型管段的网格模型与管道梁单元连接处与所述主节点对应的异型管段的网格模型的各节点为从节点,
    对所述混合模型进行有限元计算,得到混合模型的各节点的位移,包括:在异型管段的网格模型与管道梁单元连接处,只计算主节点的位移,
    所述根据异型管段的网格模型的网格节点位移,计算各壳单元的应力,具体包括:
    根据主节点的位移,计算与所述主节点对应的各从节点的位移,
    所述各从节点的位移,以及有限元计算中得到的异型管段的网格模型的其他网格节点位移,构成异型管段的网格模型的网格节点位移,
    根据所述异型管段的网格模型的网格节点位移,计算各壳单元的应力。
  6. 根据权利要求5所述的具有异型管段的管道力学计算方法,其特征在于,在根据主节点的位移,计算与所述主节点对应的各从节点的位移之前,还包括:判断工况为非温度工况还是温度工况,
    若判断工况为非温度工况,根据主节点的位移,采用下式计算与所述主节点对应的各从节点的位移:
    d′=d×a
    其中,d为主节点的位移,d′为所述主节点对应的从节点的位移,a为将主节点位移转换到从节点位移的转换矩阵;
    若判断工况为温度工况,根据主节点的位移,采用下式计算与所述主节点对应的各从节点的位移:
    d′=d×(a×(1+alf))
    其中,alf为管道材料的热膨胀系数。
  7. 一种具有异型管段的管道力学分析方法,其特征在于,包括:采用权利要求1-6任一项所述的具有异型管段的管道力学计算方法计算得到各壳单元的应力和各管道梁单元的应力,
    根据各壳单元的应力和各管道梁单元的应力,对所述具有异型管段的管道进行应力评定。
  8. 一种具有异型管段的管道力学计算装置,其特征在于,包括:
    管道梁生成模块,用于根据管道中各部件的参数信息,生成由多个管道梁单元连接组成的管道梁模型,以及各管道梁单元的节点信息,其中,部件与管道梁单元一一对应,
    壳生成模块,用于获取需详细分析的异型管段的网格划分信息,以及其在管道梁模型中的节点信息,生成由多个壳单元拼接形成的异型管段的网格模型,以及所述网格模型中的网格节点信息,
    替换模块,用于采用所述异型管段的网格模型替换管道梁模型中对应位置的管道梁单元,以形成混合模型,
    壳参数形成模块,用于计算异型管段的材料密度,并替换异型管段参数信息中的线密度,形成更新后的异型管段的参数信息,
    有限元计算模块,用于根据待计算的管道的工况信息,以及管道中各部件的参数信息,对所述混合模型进行有限元计算,得到混合模型的各节点的位移,根据管道梁单元的节点位移,计算管道梁单元的节点内力,根据异型管段的网格模型的网格节点位移,计算各壳单元的应力,
    应力计算模块,根据管道梁单元的节点内力,计算管道梁单元的应力。
  9. 根据权利要求8所述的具有异型管段的管道力学计算装置,其特征在于,还包括接口模块,用于接收待计算管道的工况信息和各部件的参数信息并传输至管道梁生成模块和有限元计算模块,且还将异型管段的参数信息分别传输至壳生成模块和壳参数形成模块;
    还用于接收异型管段的编号信息和网格划分信息并传输至壳生成模块,还将异型管段的编号信息传输至壳参数形成模块。
  10. 根据权利要求9所述的具有异型管段的管道力学计算装置,其特征在于,
    所述异型管段包括弯管,
    所述壳参数形成模块计算弯管的材料密度,具体包括:
    根据弯管的线密度w a,确定弯管的理论材料密度w a′,其计算公式为:w a′=w a/g a/t a,其中,对弯管环向分段后,端面圆形成N段圆弧,g a为圆弧的长度,g a=πD a/N,t a为弯管的壁厚,D a为弯管的管径,
    根据弯管的环向划分段数,计算弯管的环向折算密度系数fac a,其计算公式为:fac a=g a/g a′,其中,g a′为对弯管环向分段后,圆弧对应的折线段的长度,g a′=2 D a×sin(180/N),
    根据弯管的轴向划分段数,计算弯管的轴向折算密度系数fac a′,对弯管轴向分段后,弯管形成n个弯管分段,设弯管分段始末端面中心点连线的长度为L,其中,L=2R×sin(β/2n),R为弯管的弯曲半径,β为弯管的转弯角度,弯管分段的轴向中心点所在的断面椭圆周长为l,其中,断面椭圆的长轴长度a=r,断面椭圆的短轴长度b=r×cos(β/2n),轴向折算密度系数fac a′的计算公式为:fac a′=s/(n×L×l),其中,s为弯管的表面积,
    再根据下式计算弯管的材料密度w a″:
    w a″=w a′×fac a×fac a′。
  11. 根据权利要求9所述的具有异型管段的管道力学计算装置,其特征在于,所述异型管段包括三通管,
    所述三通管的参数信息包括:
    所述壳参数形成模块还与壳生成模块电连接,其计算三通管的材料密度,具体包括:
    根据主管或支管的线密度w b,确定主管或支管的理论材料密度w b′,其计算公式为:w b′=w b/g b/t b,其中,对主管或支管环向分段后,端面圆形成多段圆弧,g b为圆弧的长度,t b为主管或支管的壁厚,
    根据主管或支管模型替换前后的面积,计算主管或支管的面积折 算系数fac b,其计算公式为:fac b=A/A′,其中,
    A为主管或支管模型替换前,不考虑面积的缺失或多出,所计算得到的面积,其中,A=π×D b×L b,D为主管或支管的管径,L b为主管或支管的端部圆中心至三通管的三管中心轴线相交点的连线长度,
    A′为主管或支管模型替换后,考虑面积的缺失或多出,所计算得到的面积,所述A′具体为根据所述网格模型中主管或支管的网格节点信息,计算得到的主管或支管的壳单元面积之和,
    再根据下式计算主管或支管的材料密度:
    w b″=w b′×fac b
  12. 根据权利要求9所述的具有异型管段的管道力学计算装置,其特征在于,所述异型管段包括锥管,
    所述壳参数形成模块还与壳生成模块电连接,其计算弯管的材料密度,具体包括:
    计算所述锥管的材料密度,具体包括:
    计算锥管的重量W=w c×L c
    根据锥管的平均壁厚,其计算公式为t c=(T+t)/2,其中,T为锥管大端壁厚,t为锥管小端壁厚,
    计算锥管网格化后的表面积,其计算公式为
    Figure PCTCN2022135739-appb-100003
    Figure PCTCN2022135739-appb-100004
    其中,R c为锥管大端半径,r c为锥管小端半径,L c为锥管长度,N c为锥管环向分段数,
    根据锥管的平均壁厚,以及锥管网格化后的表面积,计算锥管的体积V=A c×t c
    再根据下式计算锥管的材料密度w c′:
    w c′=W/V。
  13. 根据权利要求8-12任一项所述的具有异型管段的管道力学计算装置,
    所述壳参数形成模块包括材料密度计算模块和参数更新模块,
    所述材料密度计算模块与接口模块电连接,用于根据异型管段的参数信息,计算异型管段的材料密度,
    所述参数更新模块与材料密度计算模块电连接,用于采用所述异型管段的材料密度替换替换异型管段参数信息中的线密度,形成更新后的异型管段的参数信息。
  14. 根据权利要求8-12任一项所述的具有异型管段的管道力学计算装置,其特征在于,
    设异型管段的网格模型与管道梁单元连接处的管道梁单元的节点为主节点,设异型管段的网格模型与管道梁单元连接处与所述主节点对应的异型管段的网格模型的各节点为从节点,
    所述有限元计算模块包括总节点位移计算模块、网格节点位移形成模块、梁单元内力计算模块和壳单元应力计算模块,
    所述总节点位移计算模块用于对所述混合模型进行有限元计算,得到混合模型的各节点的位移,其包括:在异型管段的网格模型与管道梁单元连接处,只计算主节点的位移,
    所述网格节点位移形成模块与总节点位移计算模块电连接,用于根据主节点的位移,计算与所述主节点对应的各从节点的位移,还用于将所述各从节点的位移,以及有限元计算中得到的异型管段的网格模型的其他网格节点位移汇总,构成异型管段的网格模型的网格节点位移,
    所述梁单元内力计算模块与总节点位移计算模块电连接,用于根据管道梁单元的节点位移,计算管道梁单元的节点内力,
    所述壳单元应力计算模块与网格节点位移形成模块电连接,用于 根据所述异型管段的网格模型的网格节点位移,计算各壳单元的应力。
  15. 根据权利要求14所述的具有异型管段的管道力学计算装置,其特征在于,所述有限元计算模块还包括判断模块,所述判断模块电连接于接口模块和网格节点位移形成模块之间,用于判断工况为非温度工况还是温度工况,
    若判断工况为非温度工况,则触发网格节点位移形成模块根据主节点的位移,采用下式计算与所述主节点对应的各从节点的位移:
    d′=d×a
    其中,d为主节点的位移,d′为所述主节点对应的从节点的位移,a为将主节点位移转换到从节点位移的转换矩阵;
    若判断工况为温度工况,则触发网格节点位移形成模块根据主节点的位移,采用下式计算与所述主节点对应的各从节点的位移:
    d′=d×(a×(1+alf))
    其中,alf为管道材料的热膨胀系数。
  16. 根据权利要求14所述的具有异型管段的管道力学计算装置,其特征在于,
    所述网格节点位移形成模块包括壳从节点位移计算模块和壳节点位移汇总模块,
    壳从节点位移计算模块与总节点位移计算模块电连接,用于根据主节点的位移,计算与所述主节点对应的各从节点的位移,壳节点位移汇总模块分别与壳从节点位移计算模块和总节点位移计算模块电连接,用于将所述各从节点的位移,以及有限元计算中得到的异型管段的网格模型的其他网格节点位移汇总,构成异型管段的网格模型的网格节点位移。
  17. 一种具有异型管段的管道力学分析装置,其特征在于,包括如权利要求8-16任一项所述的具有异型管段的管道力学计算装置,以及应力评定模块,
    所述应力评定模块分别与具有异型管段的管道力学计算装置的有限元计算模块和应力计算模块电连接,用于根据各壳单元的应力和各管道梁单元的应力,对所述具有异型管段的管道进行应力评定。
PCT/CN2022/135739 2022-11-23 2022-12-01 一种具有异型管段的管道力学计算方法及装置、分析方法及装置 WO2024108637A1 (zh)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202211472307.2A CN115795951A (zh) 2022-11-23 2022-11-23 一种具有异型管段的管道力学计算方法及装置
CN202211472307.2 2022-11-23

Publications (1)

Publication Number Publication Date
WO2024108637A1 true WO2024108637A1 (zh) 2024-05-30

Family

ID=85440410

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2022/135739 WO2024108637A1 (zh) 2022-11-23 2022-12-01 一种具有异型管段的管道力学计算方法及装置、分析方法及装置

Country Status (2)

Country Link
CN (1) CN115795951A (zh)
WO (1) WO2024108637A1 (zh)

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008108242A (ja) * 2006-09-26 2008-05-08 Toray Ind Inc 有限要素解析モデルの作成方法、作成装置、プログラムおよび記録媒体
CN101826117A (zh) * 2009-03-04 2010-09-08 中国核电工程有限公司 一种管道系统有限单元法力学计算模型制作方法
CN102819632A (zh) * 2012-07-26 2012-12-12 苏州工业园区设计研究院股份有限公司 一种钢框架结构节点多尺度有限元模型建模方法
CN106021644A (zh) * 2016-05-06 2016-10-12 西北工业大学 确定混合维模型界面约束方程系数的方法
CN110705169A (zh) * 2019-10-12 2020-01-17 中国电建集团成都勘测设计研究院有限公司 一种改进的贴边岔管计算模型
CN111209038A (zh) * 2020-01-02 2020-05-29 中广核工程有限公司 核级管道力学计算前处理文件格式转换系统、方法及设备
CN111428403A (zh) * 2020-03-18 2020-07-17 黄冈师范学院 基于全局寻优迭代算法的埋地柔性管道有限元简化方法
CN115329619A (zh) * 2022-06-29 2022-11-11 中国核电工程有限公司 一种核工程设备有限单元法力学综合分析系统及方法

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008108242A (ja) * 2006-09-26 2008-05-08 Toray Ind Inc 有限要素解析モデルの作成方法、作成装置、プログラムおよび記録媒体
CN101826117A (zh) * 2009-03-04 2010-09-08 中国核电工程有限公司 一种管道系统有限单元法力学计算模型制作方法
CN102819632A (zh) * 2012-07-26 2012-12-12 苏州工业园区设计研究院股份有限公司 一种钢框架结构节点多尺度有限元模型建模方法
CN106021644A (zh) * 2016-05-06 2016-10-12 西北工业大学 确定混合维模型界面约束方程系数的方法
CN110705169A (zh) * 2019-10-12 2020-01-17 中国电建集团成都勘测设计研究院有限公司 一种改进的贴边岔管计算模型
CN111209038A (zh) * 2020-01-02 2020-05-29 中广核工程有限公司 核级管道力学计算前处理文件格式转换系统、方法及设备
CN111428403A (zh) * 2020-03-18 2020-07-17 黄冈师范学院 基于全局寻优迭代算法的埋地柔性管道有限元简化方法
CN115329619A (zh) * 2022-06-29 2022-11-11 中国核电工程有限公司 一种核工程设备有限单元法力学综合分析系统及方法

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
GAO QI; NIU HAI-ZHONG; ZHAO BIN; YANG MING; YOU ZE-GUANG: "Optimization Analysis of Hole Taper Groove Tee in High Steel Grade Natural Gas Pipeline Station", PETRO-CHEMICAL EQUIPMENT, vol. 51, no. 1, 31 January 2022 (2022-01-31), pages 34 - 39, 72, XP009554828, ISSN: 1000-7466 *

Also Published As

Publication number Publication date
CN115795951A (zh) 2023-03-14

Similar Documents

Publication Publication Date Title
CN106383955B (zh) 管道设计中应力分析与三维模型的数据相互转换方法
MX2012006530A (es) Metodo de diseño para equipo submarino sujeto a agrietamiento por esfuerzo inducido por hidrógeno.
Rukavishnikov et al. Mathematical model of the pipeline with angular joint of elements
Ji et al. Optimization of aero-engine pipeline for avoiding vibration based on length adjustment of straight-line segment
Huang et al. Large-scale welding process simulation by GPU parallelized computing
CN112052616A (zh) 一种含任意腐蚀缺陷钢制管道外压临界弹塑性屈曲压力计算方法
Bathe et al. A simple and effective pipe elbow element—pressure stiffening effects
WO2024108637A1 (zh) 一种具有异型管段的管道力学计算方法及装置、分析方法及装置
US20050285855A1 (en) Method of rapidly building multiple three-dimensional pipes
Larsen et al. Optimization of welded K-node in offshore jacket structure including the stochastic size effect
CN111597648B (zh) 一种航空发动机机匣弧面管路的参数化建模方法
Attia et al. Numerical assessment of elbow element response under internal pressure
Jiang et al. Finite element predictions of temperature distributions in a multipass welded piping branch junction
CN108959702A (zh) 一种基于面偏差传递的火箭贮箱偏差分析方法
Sobel In-plane bending of elbows
WO2024108636A1 (zh) 一种管道力学计算方法及装置、分析方法及装置
Zheng et al. An interactive geometry utility environment for multi‐disciplinary computational engineering
Jeanclos et al. Derivation of minimum required model for augmented reality based stepwise construction assembly control
Wu et al. An Improvement of Probabilistic Feasible Region Method for Reliablity-Based Design Optimization
Liu et al. Geometric deformation prediction of a centrifugal impeller considering welding distortion and fluid-structure interaction
Gao Key parameter design and optimization for aviation corrugated pipe with finite element method
Rouse et al. A method to approximate the steady-state creep response of three-dimensional pipe bend finite element models under internal pressure loading using Two-dimensional axisymmetric models
Creates et al. Alignment of Stress Intensification and Flexibility Factors for The B31 Book Sections
Huang et al. Shakedown strength based parameter optimization technique and its application on designing an airtight module
CN117150673A (zh) 压力容器局部应力自动分析方法、装置及系统和存储介质

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 22966322

Country of ref document: EP

Kind code of ref document: A1