A high-efficiency modeling method for pipeline structure based on mesh deformation method

Abstract

A kind of pipeline structure high-efficiency modeling method based on mesh deformation method, creates pipeline geometric model, carries out mesh division, defines control body and control point, determines mesh deformation area, uses free deformation FFD method to carry out local mesh deformation, RBF method carries out global mesh deformation, imports the pipeline model after deformation into numerical simulation software, carries out analysis in fluid flow, aerodynamic performance, structural strength etc., calculates the performance of the pipeline after deformation under different working conditions, carries out multi-objective optimization to the design of pipeline in combination with optimization algorithm, evaluates the performance of pipeline model after deformation, if the performance of some parts does not meet the design requirement, then the position of control point is further adjusted, and finally the output result is obtained.The present application avoids the tedious process of re-meshing after each modification, significantly improves the calculation efficiency, reduces the artificial intervention in the reconstruction process by directly modifying the mesh model, saves the design and calculation time, and reduces the cost.

Description

Technical Field

[0001] This invention belongs to the field of marine ship construction and design, and specifically relates to an efficient modeling method for pipeline structures based on mesh deformation. Background Technology

[0002] As the scale of ship pipeline systems continues to expand, traditional pipeline structure modeling methods can no longer meet the demands for real-time optimization and efficient computation. Traditional methods require re-meshing every time the pipeline model is modified, resulting in high computational complexity and low efficiency. Therefore, an efficient and flexible pipeline structure modeling method is needed that can avoid re-meshing while achieving high-precision model deformation and optimization.

[0003] To avoid the drawbacks of mesh reconstruction, relatively simple and fast mesh deformation techniques are increasingly favored by researchers. Mesh deformation is a technique that allows direct modification of the mesh on the model. It is a model modification method that allows for certain deformations without changing the mesh topology. Generally, any mesh deformation will lead to a decrease in mesh quality. Therefore, it is necessary to minimize this negative impact while allowing for specific modifications to the mesh model. This requires that different models with different degrees of mesh deformation must have corresponding deformation methods that can meet their respective mesh quality requirements. Summary of the Invention

[0004] To address the aforementioned problems, this invention provides an efficient pipeline structure modeling method based on mesh deformation. The aim is to rapidly adjust the pipeline geometry without altering the mesh topology, thereby improving computational efficiency and optimizing pipeline performance. The technical solution employed is as follows: An efficient modeling method for pipeline structures based on mesh deformation is proposed, and the specific operation process is as follows: S1: Create the pipeline geometry model.

[0005] S2: Perform mesh generation to produce a preliminary mesh.

[0006] S3: Define the control volume and control points, and determine the mesh deformation region.

[0007] S4: Use the Free Deformation (FFD) method for local mesh deformation and the RBF method for global mesh deformation.

[0008] S5: Performance simulation analysis.

[0009] The deformed pipe model is imported into numerical simulation software to analyze fluid flow, aerodynamic performance, structural strength, etc., and to calculate the performance of the deformed pipe under different working conditions.

[0010] S6: Combine optimization algorithms to perform multi-objective optimization of pipeline design.

[0011] S7: Based on the simulation analysis and optimization results, evaluate the performance of the pipeline model after deformation. If the performance of certain parts does not meet the design requirements, further adjust the position of the control points.

[0012] S8: Final output result.

[0013] Furthermore, in step S4, the above-mentioned efficient pipeline structure modeling method based on mesh deformation is further improved by using the free deformation (FFD) method to define a surrounding control volume around the pipeline model, selecting the boundary of the control volume and the distribution of internal control points, and the control points covering the key parts of the pipeline.

[0014] Furthermore, in the above-mentioned efficient pipeline structure modeling method based on mesh deformation, the control volume is a three-dimensional cube or polyhedron.

[0015] Furthermore, the aforementioned efficient pipeline structure modeling method based on mesh deformation further includes key components such as elbows, joints, and deformation-sensitive areas of the pipes.

[0016] Furthermore, in step S5, the numerical simulation software used in the above-mentioned efficient pipeline structure modeling method based on mesh deformation is CFD or FEA.

[0017] Furthermore, in step S5, the performance of the deformed pipeline under different operating conditions includes flow velocity, pressure loss, and thermal expansion effects.

[0018] Furthermore, in step S6, the optimization objectives of the above-mentioned efficient pipeline structure modeling method based on mesh deformation include reducing fluid resistance, increasing flow velocity, increasing structural strength, and reducing material consumption.

[0019] This invention presents a pipeline structure modeling method based on mesh deformation, providing an efficient and flexible tool to address the challenges in pipeline structure design and optimization. By avoiding mesh reconstruction, it can significantly improve design efficiency, and further enhance the performance of the pipeline system through optimization algorithms, demonstrating broad application prospects.

[0020] This avoids the tedious process of re-meshing after each modification, significantly improving computational efficiency, especially in the modeling and optimization of complex pipeline systems. By directly modifying the mesh model, manual intervention during the reconstruction process is reduced, saving design and calculation time and lowering costs. Flexible geometric adjustments can be made to specific parts of the pipeline or the entire pipeline to meet design requirements under different operating conditions.

[0021] The beneficial effects of this invention are as follows: 1. Advantages of efficient iteration: It adopts mesh deformation technology instead of mesh reconstruction, only updating the mesh coordinates without changing the topology, which greatly reduces the computational cost and time consumption of large-scale pipeline models, and realizes rapid shape adjustment and optimization iteration.

[0022] 2. Advantages of parametric design: By combining free deformation (FFD) and radial basis function (RBF) interpolation, parametric control of pipeline shape can be achieved, which facilitates shape and component sensitivity analysis and adapts to the complex and ever-changing design requirements of ship pipelines.

[0023] 3. Precision Guarantee Advantage: It does not destroy the original mesh topology, avoids mesh reconstruction errors, ensures the calculation accuracy and stability of CFD and FEM numerical simulations, and provides reliable support for pipeline performance optimization.

[0024] 4. Engineering Adaptability Advantages: It can be seamlessly integrated into the existing ship piping design process without the need for additional mesh system reconstruction. It improves modeling efficiency while optimizing the hydraulic and structural performance of pipelines, making it suitable for the rapid design of high-density piping systems. Attached Figure Description

[0025] Figure 1 This is a flowchart of the operation of the present invention.

[0026] Figure 2 This is a three-dimensional geometric model of the original fuel pipeline structure in the engine room.

[0027] Figure 3 This is a schematic diagram of the entire process of fluid simulation mesh and structural simulation mesh deformation. Detailed Implementation

[0028] The invention will be further described with reference to the accompanying drawings, such as... Figure 1 As shown, an efficient pipeline structure modeling method based on mesh deformation is proposed. This method allows for flexible modeling and optimization of pipeline structures without re-meshing the mesh. By combining free deformation (FFD) technology, radial basis function (RBF) interpolation technology, and optimization algorithms, this method can quickly adjust the pipeline geometry without altering the mesh topology, thereby improving computational efficiency and optimizing pipeline performance.

[0029] The specific steps adopted in the technical solution of the present invention are as follows: Step 1. Mesh Generation (1) Create a preliminary pipeline geometry model Use CAD tools to create a 3D geometric model of the piping system. Ensure the piping model includes all design parameters, such as diameter, length, elbows, and joints.

[0030] (2) Generate mesh Based on the complexity of the pipeline geometry model, select an appropriate mesh type: hexahedral mesh, tetrahedral mesh, or hybrid mesh. Use numerical simulation software (such as CFD or FEA) to mesh the pipeline model and generate a preliminary mesh model.

[0031] Step 2. Mesh Deformation Preparation (1) Define the control body Using the Free Deformation (FFD) method, define a bounding control volume around the pipe model. The control volume can be a 3D cube or other polyhedron. Choose the boundaries and internal control point distribution of the control volume; typically, these control points should cover critical parts of the pipe, such as elbows, joints, or other deformation-sensitive areas.

[0032] (2) Control point adjustment Set the control points and their initial positions within the control body. The movement of each control point will directly affect the deformation of the pipeline mesh.

[0033] Step 3. Apply mesh deformation (1) Local mesh deformation The FFD method is used to locally deform the pipe mesh by moving control points. Local deformation is suitable for areas requiring precise control, such as bends, joints, or support areas in the pipe. Appropriate displacement is applied to each control point to ensure that the quality of the deformed mesh is similar to that of the original mesh.

[0034] (2) Global mesh deformation Global deformation of the entire pipeline is achieved using the radial basis function (RBF) method to apply large-scale geometric deformation to the pipeline model. Global deformation is suitable for situations requiring optimization or adjustment of the entire pipeline. The distribution and position adjustment of control points can affect the overall shape of the pipeline, such as increasing or decreasing the pipeline diameter or changing the pipeline curvature.

[0035] Step 4. Optimization and Performance Analysis (1) Performance Simulation and Analysis The deformed pipe model is imported into numerical simulation software (such as CFD or FEA) for analysis of fluid flow, aerodynamic performance, and structural strength. The performance of the deformed pipe under different operating conditions is calculated, including flow velocity, pressure loss, and the effects of thermal expansion.

[0036] (2) Combination of optimization algorithms Multi-objective optimization of pipeline design is achieved by combining optimization algorithms (such as genetic algorithms and response surface methodology). Optimization objectives may include reducing fluid resistance, increasing flow velocity, increasing structural strength, or reducing material consumption.

[0037] Step 5. Results Analysis and Adjustment (1) Result Evaluation Based on simulation and optimization results, evaluate the performance of the pipeline model after deformation. If the performance of certain parts does not meet design requirements, further adjustments are made to the control point locations.

[0038] (2) Result Output As needed, multiple iterations and adjustments are performed to optimize each part of the pipeline until the design goals are met. The final optimization and modeling of the pipeline structure is completed, and the final design document is output. It is ensured that the deformed pipeline model meets performance requirements in practical applications and can cope with various load conditions and environmental changes.

[0039] This example focuses on the lubricating oil pipeline in the engine room of an ocean-going bulk carrier. This pipeline, located between the double bottom of the engine room and the sidewall of the engine cylinder, is responsible for supplying lubricating oil to the ship's auxiliary machinery. The original design of the pipeline suffered from excessive local lubricating oil pressure loss at bends and excessive structural stress due to the combined loads of oil pressure and engine room vibration. The modeling and optimization were carried out using the complete process described in steps 1-5 of this invention, relying entirely on FFD local mesh deformation + RBF global mesh deformation technology. This eliminates the need for repeated mesh re-division, and each key node is accompanied by accompanying figure titles. The steps correspond one-to-one with the patented technical solution.

[0040] First, a geometric model of the engine room fuel lines was created, such as... Figure 2 As shown.

[0041] The original geometric model of the fuel pipeline was constructed using 3D software. Basic pipeline parameters: nominal inner diameter of the main pipe 45mm, total pipeline length 12.72m; the pipeline includes 5 90° arc stamped elbows, 1 tee joint, and 8 straight steel pipe sections. The pipeline ends connect to the lubricating oil day tank outlet and the auxiliary engine lubricating oil inlet, respectively. Design operating medium: 45℃ ambient marine lubricating oil, rated supply flow rate 0.4 m³ / h, pipeline working oil pressure 0.4 MPa. The pipeline installation constraint boundaries (bulwark fixed support positions, suspended pipe section lengths) were completely replicated, completing full-size geometric modeling.

[0042] Next, the entire pipeline area is meshed to generate the initial computational mesh. The simulation preprocessing software was used for mesh generation. A structured hexahedral mesh with a basic mesh size of 5 mm was used for straight pipe sections. Mesh refinement was applied to flow- and stress-sensitive areas such as elbows and reducers, with a refinement mesh size of 1 mm. The final initial mesh count was 1.132 million. The same initial mesh topology was used for both fluid CFD simulation and structural FEA strength simulation, meeting the numerical computation acceptance criteria. Then, FFD control volumes were defined, control points were set up, and mesh deformation regions were delineated. Next, the coordinates of control points within each elbow and joint control volume were moved individually to change the elbow curvature, achieving local pipeline profile optimization. Only the mesh node coordinates were changed, without altering the original mesh topology. Finally, based on the control points of the outer polyhedral control volume, global fine-tuning was performed on the entire straight section of the fuel pipeline, slightly optimizing the straight pipe routing and elbow node positions.

[0043] After deformation, the mesh distortion rate of the entire pipeline is <0.15, meeting the mesh quality requirements for CFD and FEA simulations. The entire deformation process is as follows: Figure 3 As shown.

[0044] The fuel pipeline calculation example in this engine compartment adopts the mesh deformation technology of this patent throughout. Compared with the traditional method of repeatedly reconstructing the mesh, it saves 6 full pipeline mesh re-division processes, significantly shortens the modeling and optimization cycle of a single pipeline, and reduces the amount of manual modeling work by 65%, fully verifying the high efficiency and low cost technical advantages of this invention.

Claims

1. An efficient modeling method for pipeline structures based on mesh deformation, characterized in that, The specific operation process is as follows: S1: Create the pipeline geometry model; S2: Perform mesh generation to produce a preliminary mesh; S3: Define the control volume and control points, and determine the mesh deformation region; S4: Use the Free Deformation (FFD) method for local mesh deformation and the RBF method for global mesh deformation; S5: Performance simulation analysis; The deformed pipe model is imported into numerical simulation software to analyze fluid flow, aerodynamic performance, and structural strength, and to calculate the performance of the deformed pipe under different working conditions. S6: Combine optimization algorithms to perform multi-objective optimization of pipeline design; S7: Based on the simulation analysis and optimization results, evaluate the performance of the pipeline model after deformation. If the performance of some parts does not meet the design requirements, further adjust the position of the control points. S8: Final output result.

2. The efficient pipeline structure modeling method based on mesh deformation according to claim 1, characterized in that, In step S4, the Free Deformation (FFD) method is used to define a bounding control volume around the pipe model, select the boundary of the control volume and the distribution of internal control points, and cover the key parts of the pipe with the control points.

3. The efficient pipeline structure modeling method based on mesh deformation according to claim 2, characterized in that, The control volume is a three-dimensional cube or polyhedron.

4. The efficient pipeline structure modeling method based on mesh deformation method according to claim 2, characterized in that, Key areas include elbows, joints, and deformation-sensitive areas of pipes.

5. The efficient pipeline structure modeling method based on mesh deformation according to claim 1, characterized in that, In step S5, the numerical simulation software is CFD or FEA.

6. The efficient pipeline structure modeling method based on mesh deformation according to claim 1, characterized in that, In step S5, the performance of the deformed pipeline under different operating conditions includes flow velocity, pressure loss, and the effect of thermal expansion.

7. The efficient pipeline structure modeling method based on mesh deformation method according to claim 1, characterized in that, In step S6, the optimization objectives include reducing fluid resistance, increasing flow velocity, increasing structural strength, and reducing material consumption.

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