A batch open water numerical simulation method based on complete modeling of propeller model

Abstract

This invention provides a batch open-water numerical simulation method based on complete propeller modeling. Step S1 determines whether the propeller's basic data includes complete blade root and tip data and supplements any missing data. Step S2 uses VB programming language to convert the propeller's two-dimensional cross-sectional coordinates to three-dimensional coordinates, achieving complete and rapid propeller blade modeling. It realizes the overall modeling of multiple components, including the hub, the front transition region of the hub, the rear transition region of the hub, and multiple blades, providing reliable model input for numerical simulation. Step S3 automatically builds the complete propeller model. Step S4 calls the OpenFOAM simulation tool in batches, applying the unsteady calculation pimpleDyMFoam model and the kOmegaSST model as turbulence models to achieve batch propeller open-water performance simulation, improving time and computer hardware utilization. This invention achieves complete and rapid creation of a three-dimensional simulation model of the propeller.

Description

Technical Field

[0001] This invention relates to the field of three-dimensional modeling of marine propellers, and in particular to a batch open-water numerical simulation method based on complete propeller modeling. Background Technology

[0002] Propellers are the primary form of ship propulsion, and in the current context of energy conservation, emission reduction, and the creation of green ship designs, in-depth research on them is necessary. Accurately and quickly constructing a 3D model helps in understanding related performance, laying the foundation for optimization and improvement. The propeller's shape is a complex geometry based on a helix. The general approach to model building is to convert the coordinates of various radii and cross-sections into 3D coordinate points, then import them into 3D modeling software. Through point-to-line and line-to-surface processing, the final model is built. There are two key points in this process: first, converting basic data into 3D coordinate data; and second, converting points into surfaces in the modeling software. This requires a high level of expertise from personnel, who must not only be familiar with the geometry of propellers but also convert data from the propeller's cylindrical coordinate system to Cartesian coordinates, and finally operate the modeling software to construct surfaces or solids from points. Manually completing this process would be time-consuming and prone to errors, affecting subsequent processing or computational analysis. Furthermore, open-water numerical simulations also need automation and templates to avoid discrepancies in results due to different software users.

[0003] Current methods exist to automate the above modeling process, but they have the following limitations:

[0004] 1. A complete propeller consists of blades and a hub. Existing methods mainly focus on the blade construction process without considering the integrity of the hub and blades. Numerical simulation of open-water propellers includes the hub and the transition area before and after the hub. Simulating individual blades is not realistic and requires additional work.

[0005] 2. In practice, in some cases, the basic data provided by the propeller designer alone is insufficient to construct a complete and accurate propeller. This is mainly due to the potential lack of necessary data on the blade tips and roots. Therefore, proper processing of the basic data is necessary before modeling. Data preprocessing is crucial, as it determines the completeness and accuracy of the constructed model, but it is not clearly reflected in existing solutions.

[0006] 3. The number of basic curves constructed for the propeller blades is limited. The curves constructed by the current method for the blade surface are tangential curves of the radius profile. The surface control lacks radial curves, which may lead to the blade shape not matching reality or being uneven.

[0007] 4. The level of automation can still be improved. In terms of numerical simulation, there is no batch processing involved, which makes it impossible to efficiently complete the full numerical simulation of open water. Summary of the Invention

[0008] To address the technical problems of existing automated modeling processes that fail to consider the integrity of the propeller hub and blades, do not address data defects before modeling, have limited basic curves for the constructed propeller blades, and lack batch processing capabilities leading to inaccurate and inefficient propeller simulation model creation, this invention proposes a batch open-water numerical simulation method based on complete propeller modeling. This method enables the complete and rapid creation of a three-dimensional simulation model of the propeller.

[0009] The specific plan is as follows:

[0010] A batch open-water numerical simulation method based on complete propeller modeling.

[0011] S1: Determine whether the propeller basic data contains complete blade root and blade tip data and supplement any missing blade root and blade tip data; if the blade and hub do not intersect, determine that there is no blade root data; if the blade tip position lacks profile value, determine that there is no blade tip data.

[0012] S2: Based on the VB conversion program, convert the propeller basic data supplemented in S1 into three-dimensional point cloud data of the propeller and obtain the three-dimensional coordinate file of the propeller.

[0013] S3: Automatically build a complete propeller model: Based on Rhino software, the Grasshopper plugin is used as a modeling tool to automatically build the geometric model. The construction of the geometric model includes: the construction of the tangential and radial curves of the propeller blades, the construction of the hub, and the construction of the front and rear transition areas.

[0014] S4: Batch Open Water Numerical Simulation: Based on OpenFOAM, batch continuous calculations are performed for multiple operating conditions. Specifically, in one simulation process, the turbulence model is set as the kOmegaSST model, and the propeller speed is kept constant. Different operating conditions are controlled by different advance speeds. After computational domain meshing and unsteady calculation, the simulation results of propeller thrust and torque are obtained. The specific configuration in OpenFOAM includes: the unsteady calculation uses the pimpleDyMFoam solver, the propeller rotation region is set as a rotating reference frame, and the variables are the propeller speed and advance speed.

[0015] Preferably, the method for supplementing the missing leaf root data in S1 is as follows:

[0016] Determine if there is a missing region without data description between 0.2 times the propeller radius R and the propeller hub (i.e., the blade root region). If so, interpolate the missing region based on the data of the known radius near the blade root.

[0017] Preferably, the method for supplementing the missing leaf tip data in S1 is as follows:

[0018] Based on the radius profile near the leaf tip, construct the profile shape value at the leaf tip; if the radius near the leaf tip is x, then the chord length at the leaf tip is 0.2 of the chord length at x; the profile shape value is proportionally changed according to the ratio of the maximum thickness at the leaf tip to that at x.

[0019] Preferably, the conversion formula in S2 for converting the basic propeller data supplemented in S1 into 3D point cloud data of the propeller according to the VB conversion program is as follows:

[0020]

[0021]

[0022]

[0023]

[0024]

[0025]

[0026] in:

[0027] , , These are the coordinates of the leaf back.

[0028] , , These are the leaf surface coordinates;

[0029] The above are the coordinates of the desired three-dimensional coordinate points. The variables below are the known basic propeller data:

[0030] The radius is ;

[0031] Pitch angle;

[0032] ;

[0033] : Pitch;

[0034] Distance from the guide edge to the reference line;

[0035] : Chord coordinates of the blade profile;

[0036] : Longitudinal coordinates of the blade back in the blade profile;

[0037] : Longitudinal coordinates of the blade profile;

[0038] It is the vertical oblique angle.

[0039] Preferably, the method for constructing the propeller blades in S3 is as follows: Grasshopper reads in a file containing the three-dimensional coordinates of the propeller and the number of blades, and automatically completes the following process:

[0040] S31: For each radius profile, starting from the trailing edge on the blade back, connect each point to the trailing edge on the blade surface one by one with a curve to form a profile curve. Since there is a repeating point on the leading edge of the blade, remove the repeating point during the connection process, and repeat the above process from the smallest radius to the blade tip;

[0041] S32: The leading edge of each radius profile curve is interrupted at this point, dividing the radius profile curve into two parts: the back of the blade and the front of the blade, thus completing the construction of the tangential curve at each radius.

[0042] S33: In the direction of the blade radius, connect the points at the same position in each radial section with curves. Each curve connects the blade root to the blade tip, thus completing the construction of the blade radial curve.

[0043] S34: Use tangential and radial curves to generate the surfaces on the underside and upper surface of the leaf, respectively;

[0044] S35: Finally, close the root section, tip section, and edge surface of the blade, and combine the back and front of the blade to form a closed whole, completing the drawing of a complete blade.

[0045] S36: Copy other blades along the propeller rotation direction according to the shape of blade S35 to complete the modeling of the complete propeller blades.

[0046] Preferably, the method for constructing the propeller hub in S3 is as follows:

[0047] In Grasshopper, enter the following parameters: front diameter of the propeller hub, front distance of the propeller hub, rear diameter of the propeller hub, and rear distance of the propeller hub; the following process will be completed automatically: the front section of the propeller hub will be drawn based on the front diameter and distance of the propeller hub, the rear section of the propeller hub will be drawn based on the rear diameter and distance of the propeller hub, and the circumferential surface of the propeller hub will be generated by lofting; the front section, rear section, and circumferential surface of the propeller hub will be combined into a closed surface to complete the modeling of the propeller hub.

[0048] Preferably, the method for constructing the transition region between the front and rear ends of the propeller in S3 is as follows:

[0049] In Grasshopper, enter the following parameters: front-end transition length, back-end transition length;

[0050] Modeling process of the front transition zone: Take a point on the edge of the front section of the propeller hub and name it point 1. Copy this point and move it forward by one-fifth of the length of the front transition zone of the propeller hub and name it point 2. On the X-axis, draw a point at a position with a length equal to the sum of the distance from the front of the propeller hub and the length of the front transition zone and name it point 3. Connect the above points 1, 2 and 3 with a spline curve. Rotate this curve 360° along the X-axis to draw a surface of revolution to complete the modeling of the front transition zone.

[0051] Modeling process of the rear transition section: Copy the edge curve of the rear section of the propeller hub and move it backward by the length of the rear transition area. Use this curve and the edge curve of the rear section of the propeller hub to form a surface by lofting. Close the rear end of the transition area and combine it with the rear section of the propeller hub to form a closed surface. This completes the modeling of the rear transition area.

[0052] Preferably, the step of numerical simulation of batch open water in S4 further includes:

[0053] Name the folders for each working condition with speed, and each folder uses the same calculation template. Modify the speed and rotation speed in the calculation template using the sed command to complete the mesh generation of the calculation domain.

[0054] The beneficial effects of the present invention are as follows:

[0055] This invention provides a batch open-water numerical simulation method based on complete propeller modeling. In step S1, considering the integrity of the propeller hub and blades, it determines whether the basic propeller data includes complete blade root and tip data and supplements any missing data. A method for supplementing missing data affecting propeller modeling is proposed. In step S2, VB is used as the programming language to convert the two-dimensional cross-sectional coordinates of the propeller into three-dimensional coordinates, enabling the complete and rapid construction of the propeller blades. In particular, compared to existing technologies, it achieves integrated modeling of multiple parts, including the hub, the front transition area of ​​the hub, the rear transition area of ​​the hub, and multiple blades, providing reliable model input for numerical simulation. In step S3, Grasshopper is used as the modeling tool to automatically build the complete propeller model, providing users with a flexible and convenient way to use and visualize the model. By adding basic curves to the constructed propeller blades, the leading edge of each radius cross-sectional curve is broken at a point, dividing the radius cross-sectional curve into two parts: the blade back and the blade front. This completes the construction of the tangential curve at each radius. In the blade radius direction, curves are used to connect points at the same position on each radius profile. Each curve connects the blade root to the blade tip, completing the construction of the blade radial curve. This makes the modeled blade shape more consistent with reality and smoother, thereby achieving tangential and radial control of propeller blade surface modeling, which is more in line with actual conditions. In step S4, the OpenFOAM simulation tool is called in batches, and the unsteady calculation pimpleDyMFoam solver is applied. The kOmegaSST model is used as the turbulence model to realize the batch simulation of propeller open water performance, improving the utilization of time and computer hardware. Attached Figure Description

[0056] Figure 1 Flowchart of a batch open water numerical simulation method based on complete propeller modeling.

[0057] Figure 2 -A typical basic data processing propeller profile diagram in embodiment A.

[0058] Figure 2 -B Embodiment: Propeller profile after blade root treatment.

[0059] Figure 3 The example uses an interactive diagram of a propeller-shaped value point generation program developed in VB.

[0060] Figure 4 The example shows the effect of constructing the tangential curve at the radius.

[0061] Figure 5 The example shows the effect of constructing the radial curve of the propeller blade.

[0062] Figure 6The curved surface effect diagram of the blade back and blade surface that constitute the blade in the embodiment.

[0063] Figure 7 The diagram shows the effect of constructing a propeller model for numerical simulation in the embodiment.

[0064] Figure 8 The diagram shows the effect of the computational domain grid partitioning in the embodiment. Detailed Implementation

[0065] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0066] like Figure 1 As shown, a batch open-water numerical simulation method based on complete propeller modeling is presented.

[0067] S1: Determine whether the propeller basic data contains complete blade root and blade tip data and supplement any missing blade root and blade tip data; if the blade and hub do not intersect, determine that there is no blade root data; if the blade tip position lacks profile value, determine that there is no blade tip data.

[0068] S2: Based on the VB conversion program, convert the propeller basic data supplemented in S1 into three-dimensional point cloud data of the propeller and obtain the three-dimensional coordinate file of the propeller.

[0069] S3: Automatically build a complete propeller model: Based on Rhino software, the Grasshopper plugin is used as a modeling tool to automatically build the geometric model. The construction of the geometric model includes the construction of the propeller blades, hub, and front and rear transition areas.

[0070] S4: Batch Open Water Numerical Simulation: Based on OpenFOAM, batch continuous calculations are performed for multiple operating conditions. Specifically, in one simulation process, the turbulence model is set as the kOmegaSST model, and the propeller speed is kept constant. Different operating conditions are controlled by different advance speeds. After computational domain meshing and unsteady calculation, the simulation results of propeller thrust and torque are obtained. The specific configuration in OpenFOAM includes: the unsteady calculation uses the pimpleDyMFoam solver, the propeller rotation region is set as a rotating reference frame, and the variables are the propeller speed and advance speed.

[0071] Data preprocessing methods in S1:

[0072] Data preprocessing mainly focuses on two parts, the first being the processing of leaf roots. Figure 2A is a typical propeller profile diagram. As can be seen from the diagram, there is a gap between the propeller hub and a point 0.2 times the propeller radius R (0.2R). This area lacks data description, is unrealistic, and affects the accuracy of the numerical simulation. Therefore, a set of data needs to be constructed in the region below 0.2R, such as at 0.13R, to realize the intersection of the blades and the hub. Figure 2 (B) Boolean operations facilitate subsequent modeling, making the blades and hub a unified whole. The data construction method involves extrapolation based on data from known radii near the blade root. Due to the small extrapolation range, the validity of the data is guaranteed, and the propeller shape constructed in this way will not change. This part of the data processing is integrated into the program that converts the basic data into a 3D point cloud.

[0073] The second part of the data preprocessing addresses the issue of missing blade tips. The basic propeller geometry data mainly includes two parts: one is characteristic data describing each radius profile, such as chord length, distance from the lead edge to the reference line, pitch, and pitch; the other is the detailed profile values ​​for each radius profile, generally composed of chord position, blade back height, and blade front height. In actual work, at the blade tip position, i.e., at 1.0R, the given chord length is 0, there are no profile values, but there are thickness values. Based on this data, it is impossible to construct a realistic propeller model to achieve the completeness of the propeller blade. According to the information provided by the basic data, without changing the geometric features, a very small profile is used to replace the original data, constructing a set of data with the same structure as other radii at the 1.0R radius. The specific method is as follows:

[0074] To maintain geometric smoothness at the propeller tip, the profile shape value at the blade tip is constructed based on the radius profile near the blade tip. For example, if the radius near the blade tip is known to be 0.975R in the basic data of a propeller, then the chord length at the blade tip is taken as 0.2 of the chord length at 0.975R. The profile shape value is then reduced accordingly based on the ratio of the maximum thickness at the blade tip to that at 0.975R. After the above steps, the profile shape value at the blade tip is constructed, achieving the completeness of the propeller modeling.

[0075] S2: Converting propeller geometry data into 3D point cloud data

[0076] Develop a data conversion program using VB as the tool ( Figure 3 The conversion formula used is as follows:

[0077]

[0078]

[0079]

[0080]

[0081]

[0082]

[0083] in:

[0084] , , These are the coordinates of the leaf back.

[0085] , , These are the leaf surface coordinates;

[0086] The above are the coordinates of the desired three-dimensional coordinate points. The variables below are the known basic propeller data:

[0087] The radius is ;

[0088] Pitch angle;

[0089] ;

[0090] : Pitch;

[0091] Distance from the guide edge to the reference line;

[0092] : Chord coordinates of the blade profile;

[0093] : Longitudinal coordinates of the blade back in the blade profile;

[0094] : Longitudinal coordinates of the blade profile;

[0095] It is the vertical oblique angle.

[0096] S3: Automatic creation of complete propeller model

[0097] Based on Rhino software, the Grasshopper plugin is used as a modeling tool to automatically create geometric models, including propeller blades, hub, and front and rear transition areas.

[0098] First, the propeller blades are constructed. Grasshopper reads the file containing the propeller's 3D coordinates and the number of blades, and automatically completes the following process: For each radius profile, starting from the trailing edge of the blade back, a curve is used to connect each point to the trailing edge of the blade front, forming a profile curve. Since there is a duplicate point on the leading edge of the blade, this duplicate point is removed during the connection process to ensure the uniqueness of the point. The above process is repeated from the smallest radius to the blade tip. Then, the leading edge of each radius profile curve is broken at this point, dividing the radius profile curve into two parts: the blade back and the blade front. This completes the construction of the tangential curve at each radius. Figure 4 Along the blade radius, points at the same location on each radial section are connected by curves, with each curve connecting the blade root to the blade tip, thus completing the construction of the blade radial curve. Figure 5 Using tangential and radial curves ( Figure 6 The process involves generating the surfaces on the blade's underside and upper side separately. Finally, the root section, tip section, and trailing edge surface are closed, and the blade's underside and upper side are combined to form a closed whole. After this process, a complete blade is drawn. Other blades are then copied along the propeller's rotation direction to create the complete propeller blade model. Points and lines created during surface creation are preserved for user inspection or other uses.

[0099] Next, construct the propeller hub. In Grasshopper, input the following parameters: front diameter of the hub, front distance of the hub, rear diameter of the hub, and rear distance of the hub. The system will automatically complete the following process: draw the front section of the hub based on the front diameter and distance; draw the rear section based on the rear diameter and distance of the hub; and generate the circumferential surface of the hub using a lofting method. Finally, combine the front section, rear section, and circumferential surface into a closed surface to complete the modeling of the propeller hub.

[0100] Finally, construct the front and rear transition regions. In Grasshopper, input the following parameters: front transition region length, rear transition region length. Front transition region modeling process: Take a point on the edge of the front section of the propeller hub, name it point 1. Copy this point and move it forward by one-fifth of the front transition region length, name it point 2. On the X-axis, draw a point at a position whose length is the sum of the distance from the front of the propeller hub and the front transition region length, name it point 3. Connect points 1, 2, and 3 with a spline curve. Rotate this curve 360° along the X-axis to draw a surface of revolution, completing the front transition region modeling. Rear transition region modeling process: Copy the rear section edge curve of the propeller hub and move it backward by the rear transition region length. Use this curve and the rear section edge curve of the propeller hub to form a surface using a lofting method, closing the rear of the transition region. Combine this with the rear section of the propeller hub to form a closed surface, completing the rear transition region modeling.

[0101] The propeller is constructed by following the steps described above. Figure 7 ).

[0102] S4: Numerical Simulation Method for Batch Open Water Projects

[0103] Once the 3D model of the propeller is constructed, open-water numerical simulation can begin. Considering the need to calculate multiple operating conditions in open-water numerical simulation, a batch processing approach is used to improve the level of automated calculation. OpenFOAM is used as the numerical simulation software, and the scripting language of the computer operating system is used as the control tool to achieve batch continuous calculation of multiple operating conditions. Specifically, the settings are: pimpleDyMFoam is selected as the calculation application, the kOmegaSST model is used as the turbulence model, the propeller's rotation region is set as a rotating reference frame, and the fvSchemes and fvSolution files for the discretization scheme and solution settings are explained.

[0104] fvSchemes file:

[0105]

[0106] fvSolution file:

[0107]

[0108] Batch processing uses a scripting language from the CentOS operating system as the execution language, where the variables are the propeller's rotational speed and advance speed. In a simulation, the rotational speed remains constant, while different advance speeds control different operating conditions. The processing script is as follows:

[0109]

[0110] Name the folders for each working condition with the same speed, and place the same calculation templates within them. Modify the speed and rotational speed in the templates using the sed command, and complete the conventional mesh generation in the main calculation unit. Figure 8 The calculation process, including the computational domain background mesh generation (blockMesh), geometric feature extraction (surfaceFeatureExtract), and geometry-fitting mesh generation (snappyHexMesh), is used to discretize the computational domain, serving as the basis for subsequent finite volume method simulations. The interface of the propeller rotation region is described (createPatch). The calculation process uses the OpenFOAM pimpleDyMFoam solver to simulate propeller rotation, and the results are the propeller thrust and torque.

[0111] The above embodiments are merely illustrative examples to clearly illustrate the present invention and are not intended to limit the implementation of the invention. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is impossible to exhaustively list all possible implementations here. All obvious variations or modifications derived from the technical solutions of this invention are still within the scope of this invention.

Claims

1. A batch open-water numerical simulation method based on complete propeller modeling, characterized in that, S1: Determine whether the propeller basic data contains complete blade root and blade tip data and supplement any missing blade root and blade tip data; if the blade and hub do not intersect, determine that there is no blade root data; if the blade tip position lacks profile value, determine that there is no blade tip data. S2: Based on the VB conversion program, convert the propeller basic data supplemented in S1 into three-dimensional point cloud data of the propeller and obtain the three-dimensional coordinate file of the propeller. S3: Automatically build a complete propeller model: Based on Rhino software and using the Grasshopper plugin as a modeling tool, automatically build the propeller geometric model. The content of building the geometric model includes the construction of the tangential and radial curves of the propeller blades, and the construction of the hub and the front and rear transition areas. S4: Batch Open Water Numerical Simulation: Based on OpenFOAM, batch continuous calculations are performed for multiple operating conditions. Specifically, in one simulation process, the turbulence model is set as the kOmegaSST model, and the propeller speed is kept constant. Different operating conditions are controlled by different advance speeds. After computational domain meshing and unsteady calculation, the simulation results of propeller thrust and torque are obtained. The specific configuration in OpenFOAM includes: the unsteady calculation uses the pimpleDyMFoam solver, the propeller rotation region is set as a rotating reference frame, and the variables are the propeller speed and advance speed.

2. The method for batch open water numerical simulation based on complete modeling of propeller according to claim 1, characterized in that, The method for supplementing the missing leaf root data in S1 is as follows: Determine if there is a missing region without data description between 0.2 times the propeller radius R and the propeller hub (i.e., the blade root region). If so, interpolate the missing region based on the data of the known radius near the blade root.

3. The batch open-water numerical simulation method based on complete propeller modeling as described in claim 1, characterized in that, The method for supplementing the missing leaf tip data in S1 is as follows: Based on the radius profile near the leaf tip, construct the profile shape value at the leaf tip; if the radius near the leaf tip is x, then the chord length at the leaf tip is 0.2 of the chord length at x; the profile shape value is proportionally changed according to the ratio of the maximum thickness at the leaf tip to that at x.

4. The batch open-water numerical simulation method based on complete propeller modeling as described in claim 1, characterized in that, In S2, the conversion formula for converting the basic propeller data supplemented in S1 into 3D point cloud data of the propeller using the VB conversion program is as follows: in: , , These are the coordinates of the leaf back. , , These are the leaf surface coordinates; The above are the coordinates of the desired three-dimensional coordinate points. The variables below are the known basic propeller data: The radius is ; Pitch angle; ； : Pitch; Distance from the guide edge to the reference line; : Chord coordinates of the blade profile; : Longitudinal coordinates of the blade back in the blade profile; : Longitudinal coordinates of the blade profile; It is the vertical oblique angle.

5. The batch open-water numerical simulation method based on complete propeller modeling as described in claim 1, characterized in that, In S3, the method for constructing propeller blades is as follows: Grasshopper reads in a file containing the propeller's 3D coordinates and the number of blades, and automatically completes the following process: S31: For each radius profile, starting from the trailing edge of the blade back, connect each point to the trailing edge of the blade surface one by one with a curve to form a profile curve; since there is a repeating point on the leading edge of the blade, remove the repeating point during the connection process, and repeat the above process from the smallest radius to the blade tip. S32: The leading edge of each radius profile curve is interrupted at this point, dividing the radius profile curve into two parts: the back of the blade and the front of the blade, thus completing the construction of the tangential curve at each radius. S33: In the direction of the blade radius, connect the points at the same position in each radial section with curves. Each curve connects the blade root to the blade tip, thus completing the construction of the blade radial curve. S34: Use tangential and radial curves to generate the surfaces on the back and front of the leaf, respectively; S35: Finally, close the root section, tip section, and edge surface of the blade, and combine the back and front of the blade to form a closed whole, completing the drawing of a complete blade. S36: Copy other blades along the propeller rotation direction according to the shape of blade S35 to complete the modeling of the complete propeller blades.

6. The batch open-water numerical simulation method based on complete propeller modeling as described in claim 1, characterized in that, The method for constructing the propeller hub in S3 is as follows: In Grasshopper, enter the following parameters: front diameter of the propeller hub, front distance of the propeller hub, rear diameter of the propeller hub, and rear distance of the propeller hub; the following process will be completed automatically: the front section of the propeller hub will be drawn based on the front diameter and distance of the propeller hub, the rear section of the propeller hub will be drawn based on the rear diameter and distance of the propeller hub, and the circumferential surface of the propeller hub will be generated by lofting; the front section, rear section, and circumferential surface of the propeller hub will be combined into a closed surface to complete the modeling of the propeller hub.

7. The batch open-water numerical simulation method based on complete propeller modeling as described in claim 1, characterized in that, The method for constructing the transition region between the front and rear ends of the propeller in S3 is as follows: In Grasshopper, enter the following parameters: front-end transition length, back-end transition length; Modeling process of the front transition zone: Take a point on the edge of the front section of the propeller hub and name it point 1. Copy this point and move it forward by one-fifth of the length of the front transition zone of the propeller hub and name it point 2. On the X-axis, draw a point at a position with a length equal to the sum of the distance from the front of the propeller hub and the length of the front transition zone and name it point 3. Connect the above points 1, 2 and 3 with a spline curve. Rotate this curve 360° along the X-axis to draw a surface of revolution to complete the modeling of the front transition zone. Modeling process of the rear transition section: Copy the edge curve of the rear section of the propeller hub and move it backward by the length of the rear transition area. Use this curve and the edge curve of the rear section of the propeller hub to form a surface by lofting. Close the rear end of the transition area and combine it with the rear section of the propeller hub to form a closed surface. This completes the modeling of the rear transition area.

8. The batch open-water numerical simulation method based on complete propeller modeling as described in claim 1, characterized in that, The steps for numerical simulation of batch open water in S4 also include: Name the folders for each working condition with speed, and each folder uses the same calculation template. Modify the speed and rotation speed in the calculation template using the sed command to complete the mesh generation of the calculation domain.

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