A method and system for three-dimensional design of a ship for finite element analysis

Abstract

The application provides a ship three-dimensional design method and system for finite element analysis, comprising the following steps: S1, obtaining a ship design specification, wherein the ship design specification comprises design information such as ship length, ship width, ship height, ship speed and ship structure requirements; S2, constructing an entity model in a three-dimensional design software according to the ship design specification; S3, obtaining structure information of a plate, a profile, a knee plate and a hole in the entity model, generating a facet structure according to the structure information in the entity model, and combining corresponding material properties such as material density, elastic modulus, Poisson's ratio and yield limit in a model base library to generate a facet model for finite element analysis; and S4, performing finite element analysis on the facet model, and adjusting the constructed entity model in the three-dimensional design software according to the finite element analysis result. The method reduces the operation of a designer, improves the model design efficiency and shortens the ship design cycle.

Description

Technical Field

[0001] This application relates to the field of ship three-dimensional design technology, and more specifically, to a ship three-dimensional design method and system for finite element analysis. Background Technology

[0002] With the continuous advancement of intelligent shipbuilding, the application of 3D design in the shipbuilding field is becoming increasingly widespread. Before the 3D model design of a ship is finalized, the strength calculation of the ship structure is usually performed using a finite element mesh model. However, existing 3D design software does not yet have the function of converting solid models into finite element analysis models. Therefore, the mainstream 3D ship design mode often adopts a linear design mode of "ship design specifications - patch model - finite element analysis - solid model". That is, a patch model is first built according to the ship design specifications, finite element analysis is performed based on the patch model, and then a solid model is built after the finite element analysis is completed. This design mode often has the problem that the patch model cannot meet the accuracy requirements of finite element analysis, and the patch model often needs to be adjusted repeatedly, which increases the design time. In addition, in some cases, when building a ship collaborative design and generative design model, a solid model is directly built. Later, in order to meet the requirements of finite element analysis, the designer re-builds the patch model based on the ship design specifications, which also increases the design time.

[0003] Therefore, there is an urgent need to find a novel three-dimensional ship design method to solve the above problems. Summary of the Invention

[0004] The purpose of this application is to provide a method and system for three-dimensional ship design using finite element analysis, which solves the problems of repetitive design work, insufficient application of solid models, and single digital source of models in the design mode. At the same time, it reduces the designer's operation, improves the efficiency of model design, and shortens the ship design cycle.

[0005] In a first aspect, this application provides a three-dimensional design method for ships using finite element analysis, comprising:

[0006] S1. Obtain ship design specifications, which include design information such as ship length, ship width, ship height, speed, and ship structural requirements;

[0007] S2. Construct a solid model in 3D design software according to ship design specifications;

[0008] S3. Obtain the structural information of plates, profiles, elbows and holes in the solid model, generate patch structures based on the structural information in the solid model, and then combine the corresponding material properties such as material density, elastic modulus, Poisson's ratio and yield strength in the model base library to generate patch models for finite element analysis.

[0009] S4. Perform finite element analysis on the face model, and adjust the solid model already built in the 3D design software based on the finite element analysis results.

[0010] In one implementation, in S2, constructing the solid model in the 3D design software according to ship design specifications includes:

[0011] S21. Construct a coordinate system based on the ship's length, beam, and height;

[0012] S22. Based on the speed and structural strength requirements of the ship, perform solid modeling of the hull within the constructed coordinate system;

[0013] S23. Based on the ship's structural requirements, construct the internal structure of the hull and build a solid model. The ship's structural requirements include the material and specification requirements for profiles and plates.

[0014] In one implementation, step S3, obtaining the structural information of the sheet metal, profile, elbow plate, and holes in the solid model, includes:

[0015] Obtain the structural information of the plates within the node, including the plate's location, boundaries, thickness, orientation, and material;

[0016] Obtain the structural information of the profiles within the node, including the profile's location, boundaries, orientation, and material;

[0017] Obtain the structural information of the elbow plate within the node, including the elbow plate type, boundary, parameters, orientation, and material;

[0018] Obtain structural information about the holes inside the node, including the location, type, and parameters of the holes.

[0019] In one implementation, in step S3, generating the patch structure based on the structural information in the solid model includes:

[0020] Based on the obtained structural information of the board, the shape and spatial position of the board are calculated, and the surface structure of the board is generated.

[0021] Based on the obtained structural information of the profile, the length, spatial position and offset of the profile are calculated to generate the surface structure of the profile;

[0022] Based on the obtained structural information of the elbow plate, the outline and position offset of the elbow plate are calculated, and the surface structure of the elbow plate is generated.

[0023] Based on the obtained hole parameters, the hole area is calculated, and the holes to be made in the patch structure are selected according to the area. Then, the holes are made in the patch structure in combination with the hole structure information.

[0024] In one implementation, the step of selecting the holes to be created in the patch structure based on area includes:

[0025] Based on the accuracy requirements of finite element analysis, the process specifications of the holes, and the experience of the analysts, an area threshold is set.

[0026] Compare the calculated area of ​​all holes with the area threshold;

[0027] Holes with an area smaller than the area threshold are removed, and holes with an area greater than the area threshold are selected as the holes to be created in the patch structure.

[0028] In one implementation, the node is a point where plates, profiles, and elbows are intersected and connected.

[0029] Secondly, this application also provides a three-dimensional ship design system for finite element analysis, comprising:

[0030] The acquisition module is used to acquire ship design specifications, which include design information such as ship length, ship width, ship height, speed and ship structural requirements.

[0031] The solid model building module constructs solid models in 3D design software according to ship design specifications.

[0032] The patch model construction module obtains the structural information of plates, profiles, elbows and holes in the solid model, generates patch structures based on the structural information in the solid model, and then combines the corresponding material properties such as material density, elastic modulus, Poisson's ratio and yield strength in the model base library to generate patch models for finite element analysis.

[0033] The finite element analysis module is used to perform finite element analysis on the surface model and adjust the solid model already built in the 3D design software based on the finite element analysis results.

[0034] The beneficial effects of the ship three-dimensional design method and system for finite element analysis in this application are as follows:

[0035] 1. The design methodology provides a 3D design method for converting solid models into patch models, which addresses the issues of repetitive design work, insufficient application of solid models, and the single digital source of models in the design mode, thereby improving the efficiency of 3D design software for ship hull production design; improving production design efficiency and shortening the ship design cycle.

[0036] 2. Reduce repetitive modeling work, maximize the use of design models, reduce designer operations, and improve model design efficiency;

[0037] 3. It has promoted the development of knowledge engineering and digital design. Attached Figure Description

[0038] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1 This is a flowchart illustrating a three-dimensional ship design method for finite element analysis according to an embodiment of this application. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0041] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0042] Figure 1 This is a flowchart illustrating a three-dimensional ship design method for finite element analysis according to an embodiment of this application. See also... Figure 1 ,

[0043] S1. Obtain ship design specifications, which include design information such as ship length, ship width, ship height, speed, and ship structural requirements;

[0044] S2. Construct a solid model in 3D design software according to ship design specifications;

[0045] S3. Obtain the structural information of plates, profiles, elbows and holes in the solid model, generate patch structures based on the structural information in the solid model, and then combine the corresponding material properties such as material density, elastic modulus, Poisson's ratio and yield strength in the model base library to generate patch models for finite element analysis.

[0046] S4. Perform finite element analysis on the face model, and adjust the solid model already built in the 3D design software based on the finite element analysis results.

[0047] In the aforementioned implementation process, this application provides a novel 3D ship design model for finite element analysis, employing a cyclical design method of ship design specifications - solid model - patch model - finite element analysis - solid model. Specifically, based on ship design specifications, a solid model is first constructed; structural information from the solid model is used to construct a patch model; finite element analysis is performed based on the patch model; and the solid model is then fine-tuned using the finite element analysis results. This process of converting from a solid model to a patch model, and then fine-tuning the solid model based on the patch model, solves the problem of repetitive design work in traditional design models, avoids insufficient application of the solid model and the problem of a single digital source for the model, and also avoids the issue of patch models not meeting the accuracy requirements of finite element analysis, thus improving the efficiency of 3D design software for ship hull production design.

[0048] In one implementation, in S2, constructing a solid model in 3D design software according to ship design specifications includes:

[0049] S21. Construct a coordinate system based on the ship's length, beam, and height;

[0050] S22. Based on the speed and structural strength requirements of the ship, perform solid modeling of the hull within the constructed coordinate system;

[0051] S23. Based on the ship's structural requirements, construct the internal structure of the hull and build a solid model. The ship's structural requirements include the material and specification requirements for profiles and plates.

[0052] In the above implementation process, a solid model was first constructed based on the design specifications, and then a surface patch model was constructed based on the solid model. In this way, the constructed surface patch model can eliminate hole structures that would cause errors in the calculation results. The surface patch model constructed in this way not only meets the accuracy requirements of finite element analysis, but also guides the preceding solid model.

[0053] In one implementation, step S3, obtaining the structural information of the sheet metal, profile, elbow plate, and holes in the solid model, includes:

[0054] Obtain the structural information of the plates within the node, including the plate's location, boundaries, thickness, orientation, and material;

[0055] Obtain the structural information of the profiles within the node, including the profile's location, boundaries, orientation, and material;

[0056] Obtain the structural information of the elbow plate within the node, including the elbow plate type, boundary, parameters, orientation, and material;

[0057] Obtain structural information about the holes inside the node, including the location, type, and parameters of the holes.

[0058] Among them, the node can be a place where plates, profiles and elbows are intersected and connected.

[0059] In one implementation, in S3, generating the patch structure based on the structural information in the solid model includes:

[0060] Based on the obtained structural information of the board, the shape and spatial position of the board are calculated, and the surface structure of the board is generated.

[0061] Based on the obtained structural information of the profile, the length, spatial position and offset of the profile are calculated to generate the surface structure of the profile;

[0062] Based on the obtained structural information of the elbow plate, the outline and position offset of the elbow plate are calculated, and the surface structure of the elbow plate is generated.

[0063] Based on the obtained hole parameters, the hole area is calculated, and the holes to be made in the patch structure are selected according to the area. Then, the holes are made in the patch structure in combination with the hole structure information.

[0064] In the above implementation process, profile information is obtained from the solid model, the profile position and length are calculated, and the offset in the patch model is generated to create a profile patch model; elbow plate information is obtained from the solid model, the elbow plate's spatial position and contour are calculated, and an elbow plate model is generated in the patch model; hole information is obtained from the solid model, the hole contour and area are calculated, and a hole model is generated. By obtaining structural information from the solid model to calculate the patch structure of the structure, the designer's operations can be reduced, and the model design efficiency can be improved.

[0065] To avoid the impact of small holes on finite element analysis, in one implementation scheme, a patch model is constructed based on a solid model. Holes to be created in the patch structure can be selected based on their area, including:

[0066] Based on the accuracy requirements of finite element analysis, the process specifications of the holes, and the experience of the analysts, an area threshold is set.

[0067] Compare the calculated area of ​​all holes with the area threshold;

[0068] Holes with an area smaller than the area threshold are removed, and holes with an area greater than the area threshold are selected as the holes to be created in the patch structure.

[0069] On the other hand, this application also provides a three-dimensional ship design system for finite element analysis, comprising:

[0070] The acquisition module is used to acquire ship design specifications, which include design information such as ship length, ship width, ship height, speed and ship structural requirements.

[0071] The solid model building module constructs solid models in 3D design software according to ship design specifications.

[0072] The patch model construction module obtains the structural information of plates, profiles, elbows and holes in the solid model, generates patch structures based on the structural information in the solid model, and then combines the corresponding material properties such as material density, elastic modulus, Poisson's ratio and yield strength in the model base library to generate patch models for finite element analysis.

[0073] The finite element analysis module is used to perform finite element analysis on the surface model and adjust the solid model already built in the 3D design software based on the finite element analysis results.

[0074] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A three-dimensional design method for ships using finite element analysis, characterized in that, include: S1. Obtain ship design specifications, which include design information such as ship length, ship width, ship height, speed, and ship structural requirements; S2. Constructing a solid model in 3D design software according to ship design specifications, wherein S2, constructing a solid model in 3D design software according to ship design specifications includes: S21. Construct a coordinate system based on the ship's length, beam, and height; S22. Based on the speed and structural strength requirements of the ship, perform solid modeling of the hull within the constructed coordinate system; S23. Construct the internal structure of the hull according to the ship's structural requirements, and construct a solid model. The ship's structural requirements include the material and specification requirements for profiles and plates. S3. Obtain the structural information of plates, profiles, elbows and holes in the solid model, generate patch structures based on the structural information in the solid model, and then combine the corresponding material properties such as material density, elastic modulus, Poisson's ratio and yield strength in the model base library to generate patch models for finite element analysis. Obtain the structural information of the holes inside the node, including the location, type and parameters of the holes. Calculate the area of ​​the holes based on the obtained hole parameters. Filter out the holes to be opened in the patch structure based on the area, and then open the holes in the patch structure in combination with the hole structural information. The step of selecting the holes to be made in the patch structure based on area includes: Based on the accuracy requirements of finite element analysis, the process specifications of the holes, and the experience of the analysts, an area threshold is set. Compare the calculated area of ​​all holes with the area threshold; Holes with an area smaller than the area threshold are removed, and holes with an area greater than the area threshold are selected as the holes to be created in the patch structure. S4. Perform finite element analysis on the face model, and adjust the solid model already built in the 3D design software based on the finite element analysis results.

2. The three-dimensional ship design method for finite element analysis according to claim 1, characterized in that, In step S3, obtaining the structural information of the plate, profile, elbow plate, and hole in the solid model includes: Obtain the structural information of the plates within the node, including the plate's location, boundaries, thickness, orientation, and material; Obtain the structural information of the profiles within the node, including the profile's location, boundaries, orientation, and material; Obtain the structural information of the elbow plate within the node, including the elbow plate type, boundary, parameters, orientation, and material.

3. The three-dimensional ship design method for finite element analysis according to claim 2, characterized in that, In step S3, generating the patch structure based on the structural information in the solid model includes: Based on the obtained structural information of the board, the shape and spatial position of the board are calculated, and the surface structure of the board is generated. Based on the obtained structural information of the profile, the length, spatial position and offset of the profile are calculated to generate the surface structure of the profile; Based on the obtained structural information of the elbow plate, the contour and position offset of the elbow plate are calculated, and the surface structure of the elbow plate is generated.

4. The three-dimensional ship design method for finite element analysis according to claim 2, characterized in that, The node is the point where plates, profiles, and elbows intersect and connect with each other.

5. A three-dimensional ship design system for finite element analysis, employing the three-dimensional ship design method for finite element analysis as described in any one of claims 1-4, characterized in that, include: The acquisition module is used to acquire ship design specifications, which include design information such as ship length, ship width, ship height, speed and ship structural requirements. The solid model building module constructs solid models in 3D design software according to ship design specifications. The patch model construction module obtains the structural information of plates, profiles, elbows and holes in the solid model, generates patch structures based on the structural information in the solid model, and then combines the corresponding material properties such as material density, elastic modulus, Poisson's ratio and yield strength in the model base library to generate patch models for finite element analysis. The finite element analysis module is used to perform finite element analysis on the surface model and adjust the solid model already built in the 3D design software based on the finite element analysis results.

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