A pre-deformation design method for composite propeller with metal lining structure

Abstract

The present invention relates to a pre-deformation design method for a composite propeller with a metal lining structure. The metal blade geometry model is used as a design input. Finite element modeling of the entire blade composite laminate and the metal lining is performed on an ANSYS Workbench platform. In ACP (Post), a failure criterion is selected to perform failure evaluation on each ply unit of the blade to determine whether the strength requirement is met. A hydrodynamic calculation model is constructed according to the deformed blade geometry model. The blade performance and pressure distribution are obtained by solving a fluid dynamic analysis module, and convergence judgment is performed on the hydrodynamic performance calculation results. The blade hydrodynamic force and composite material strength calculation are realized by components such as Fluent, ACP and Static Structural. The data transmission operation is simple and the interaction is convenient based on the ANSYS Workbench platform, so that a comprehensive analysis of the composite propeller performance is completed.

Description

Technical Field

[0001] The invention relates to a design method for a composite material propeller blade in the field of ship power propulsion. Background Art

[0002] In the current design and calculation of composite propellers, all-composite solid structures are often used. For full-scale marine propellers, due to the difficulty of process molding, the solid structure blades prepared and molded are somewhat different from the expected appearance, which has a great impact on the hydrodynamic performance of the propeller. If the design is reasonable, the composite propeller can not only maintain the same hydrodynamic performance as the metal propeller, but also reduce the weight compared to the metal propeller, which will also bring improvements in vibration and noise. Summary of the invention

[0003] The purpose of the present invention is to solve the problems of poor feasibility and shape accuracy of the current composite propeller blade design, and to provide a design method for a composite propeller with a metal liner structure taking pre-deformation into consideration.

[0004] To achieve the above object, the technical solution of the present invention is: a pre-deformation design method for a composite propeller with a metal lining structure, which uses a metal blade geometry model as a design input and is implemented by the following steps:

[0005] Step 1: Extract the blade geometry pressure surface and suction surface sheet models in the 3D modeling software and import them into the ANSYS WORKBENCH platform ACP module;

[0006] Step 2: In the ACP (Pre) submodule, complete the definition of metal and composite properties, finite element meshing of the blade pressure and suction surfaces, and definition of the blade composite layer. When defining the composite layer, create different Stackups and Sub Laminates to establish the finite element model of the blade composite laminate and metal liner, and pass the mesh, geometry, material properties, and composite material definition defined in the ACP module to the Mechanical module.

[0007] Step 3: Build a hydrodynamic calculation model based on the blade geometry model, use the fluid dynamics analysis module to solve the blade performance and pressure distribution, and pass the calculation results to the Mechanical module;

[0008] Step 4: Add constraints to the blade finite element model in the Mechanical module, load the blade surface pressure distribution, obtain the blade deformation in all directions, and output the Cartesian coordinates (X0, Y0, Z0) of each characteristic node of the blade and the deformation result (U X ,U Y ,U Z), and obtain the Cartesian coordinates of each node after deformation (X0+U X , Y0+U Y , Z0+U Z );

[0009] Step 5: In ACP (Post), select the failure criteria and perform failure evaluation on each ply unit of the blade to determine whether the strength requirements are met. If not, return to the ACP (Pre) module to adjust the composite material plies, including ply thickness, ply angle, etc., until the strength requirements are met.

[0010] Step 6: Based on the data obtained in step 4, reconstruct the profiles of each radius of the blade to obtain a geometric model of the deformed composite blade;

[0011] Step 7: Construct a hydrodynamic calculation model based on the deformed blade geometry model, use the fluid dynamic analysis module to solve the blade performance and pressure distribution, and perform convergence judgment on the hydrodynamic performance calculation results. If converged, output the blade geometry model at this time and the coordinates of each node (X1, Y1, Z1); if not converged, repeat steps 3 to 7 until the hydrodynamic performance calculation results converge;

[0012] Step 8: Based on the blade geometry obtained in step 7 and the initial metal blade geometry in step 1, the Cartesian coordinates of the corresponding nodes are used to perform pre-deformation processing, that is, the node coordinates (2X0-X1, 2Y0-Y1, 2Z0-Z1) are taken to construct a pre-deformed blade geometry model, which is the natural state geometry of the pre-deformed blade;

[0013] Step 9: Based on the pre-deformed blade geometry obtained in step 8, repeat steps 1 to 7 to obtain the working state geometry of the pre-deformed composite propeller after the hydrodynamic performance calculation results converge;

[0014] Step 10: Assess the hydrodynamic efficiency of the composite propeller in working state obtained in step 9. If the hydrodynamic performance requirements are met, output the composite propeller layup plan and its natural state geometry value. If the hydrodynamic performance requirements are not met, adjust the layup thickness, layup angle, etc. in step 5 until the specified hydrodynamic performance requirements are met.

[0015] In step 2: the layer material loads the upstream material property information; Fabrics defines the material and thickness of the single-layer board, with a thickness of 0.3mm, and defines the aluminum alloy metal lining with a thickness of 5mm; Stackups defines the information of the multi-layer board, including the stacking order and symmetry rules of the single-layer board, and the angle of each single-layer board; Sub Laminates defines the sub-laminate information, including the stacking order and symmetry rules of the single-layer board and the multi-layer board; the multi-layer board laying angle is set to [30° / 30° / 0° / 0° / -30°]s, and different sub-laminates are used to lay each area of ​​the blade. According to the thickness change of the original metal blade, the blade is divided into 4 areas, namely 120 layers in the root section, two middle sections: 120 layers-80 layers gradient and 80 layers-60 layers gradient, and 60 layers in the tip section. Each area has a 5mm aluminum alloy lining layer.

[0016] In step 2: use Element Sets to define the blade regions; Edge Sets to define the boundaries of the blade regions; Rosettes to define the form of the laying coordinate system; Oriented Selection Sets to define the laying reference point and laminate laying direction for the selected region, and select the laying coordinate system.

[0017] In step 2: Use Modeling Groups to add sub-layer materials, angles, and number of layers to the selected Oriented Selection Sets.

[0018] In step five: select the Caiwu failure criterion, perform failure evaluation on each ply unit of the composite blade, and determine whether it meets the strength requirements. When the thickness of the aluminum alloy lining is 5 mm, there is an area where the inverse reserve factor is greater than 1 after judgment using the Caiwu failure criterion, that is, some blade units are damaged. Therefore, it is necessary to return to step two and adjust the ply structure in the Pre module of ACP. The thickness of the aluminum alloy lining is increased to 8 mm. After updating the blade finite element model information in step four, the maximum value of the inverse reserve factor of the blade unit obtained in step five is less than 1, which meets the strength requirements of the Caiwu failure criterion.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. The pre-deformation design method adopted in the present invention can perform finite element modeling of the entire blade composite laminate and metal liner on the ANSYS Workbench platform. The method is simple, time-saving and computationally intensive.

[0021] 2. The hydrodynamic calculation and composite material strength calculation of the blades involved in the present invention are implemented by components such as Fluent, ACP and Static Structural. The data transmission operation is simple and the interaction is convenient based on the ANSYS Workbench platform, which can complete the comprehensive analysis of the performance of composite propellers. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a geometrical schematic diagram of the blade in the natural state of the present invention;

[0023] Figure 2 is a schematic diagram of the ply design of the present invention;

[0024] Figure 3 It is a design flow chart of the present invention. DETAILED DESCRIPTION

[0025] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0026] like Figure 3 As shown, a pre-deformation design method for a metal lining structure composite propeller, the implementation steps are as follows:

[0027] Step 1: Extract the sheet models of the pressure surface and suction surface of the propeller blade geometric model in the 3D modeling software, and import them into the Geometry module of the ANSYS WORKBENCH platform. The suction surface and pressure surface sheets are combined into one component and transmitted to the Geometry submodule of the ACP module.

[0028] Step 2: Add the mechanical properties of T300 carbon fiber prepreg unidirectional composite materials and aluminum alloy material properties in the ACP (Pre) submodule Engineering Data, and perform finite element meshing on the blade in the submodule Model. Complete the definition of the blade composite material, area, laying direction, etc. in Setup.

[0029] Materials loads the upstream material property information; Fabrics defines the material and thickness of the single-layer board, with a thickness of 0.3mm, and defines the aluminum alloy metal lining, with a thickness of 5mm; Stackups defines the information of the multi-layer board, including the stacking order and symmetry rules of the single-layer board, the angle of each single-layer board, etc.; Sub Laminates defines the sub-laminate information, including the stacking order and symmetry rules of the single-layer board and the multi-layer board. The multi-layer board laying angle is set to [30° / 30° / 0° / 0° / -30°]s. Different sub-laminates can be used for laying in each area of ​​the blade. According to the thickness change of the original metal blade, the blade is divided into 4 areas, namely the root section with 120 layers, the middle section (two sections: 120 layers-80 layers gradient and 80 layers-60 layers gradient), and the tip section with 60 layers. Each area has a 5mm aluminum alloy lining layer.

[0030] Element Sets define the blade regions; Edge Sets define the boundary lines of the blade regions; Rosettes define the form of the laying coordinate system (parallel, radial, cylindrical, spherical, etc.); Oriented Selection Sets define the laying reference point and laminate laying direction for the selected area, and select the laying coordinate system.

[0031] Modeling Groups adds sub-layer materials (single-layer boards, multi-layer boards, and sub-laminates), angles, and number of layers to the selected Oriented Selection Sets. Here you can define the thickness gradient rules at the junction line.

[0032] Through the above steps, a finite element model of the composite laminate and metal liner of the blade is established, and the mesh, geometry, material properties and composite material definition defined in the ACP module are transferred to the Mechanical module.

[0033] Step 3: Construct a hydrodynamic calculation model based on the blade geometry model, use the fluid dynamics analysis module to solve the blade performance and surface pressure distribution, and pass the calculation results to the Mechanical module.

[0034] Step 4: Add constraints to the blade finite element model in the Mechanical module, load the blade surface pressure distribution, obtain the blade deformation in all directions, and output the Cartesian coordinates (X0, Y0, Z0) and deformation results (U X ,U Y ,U Z ), and obtain the Cartesian coordinates of each node after deformation (X0+U X , Y0+U Y , Z0+UZ ).

[0035] Step 5: In ACP (Post), select the Cai Wu failure criterion, and perform failure evaluation on each ply unit of the composite blade to determine whether it meets the strength requirements. When the thickness of the aluminum alloy liner is 5 mm, the inverse reserve factor (IRF) after judgment by the Cai Wu failure criterion exists in an area greater than 1, that is, some blade units have been damaged. Therefore, it is necessary to return to step 2 and adjust the ply structure in the ACP (Pre) module. The thickness of the aluminum alloy liner is increased to 8 mm. After updating the blade finite element model information in step 4, the maximum value of the blade unit inverse reserve factor obtained in step 5 is less than 1, which meets the strength requirements of the Cai Wu failure criterion.

[0036] Composite blade structure and layup design are attached. Figure 1 and attached Figure 2 The laying angle of the composite laminate is [30° / 30° / 0° / 0° / -30°]s, and the laying area is divided into 4 areas. Area I lays 120 layers, that is, [[30° / 30° / 0° / 0° / -30°]s]12, Area II lays 120-80 layers decreasingly, Area III lays 80-60 layers decreasingly, and Area IV lays 60 layers. The laminate is lined with 8mm aluminum alloy.

[0037] Step 6: Based on the blade data that meets the strength requirements obtained in step 4, reconstruct the profile lines of the blade 0.3R-0.95R as well as the leading edge and trailing edge to obtain the geometric model of the composite blade after deformation due to loading hydrodynamic force.

[0038] Step 7: Construct a hydrodynamic calculation model based on the deformed blade geometry model, use the fluid dynamics analysis module to solve the blade performance and pressure distribution, and perform convergence judgment on the hydrodynamic performance calculation results. The judgment standard is that the efficiency difference is less than 0.2%, which is convergence. Then output the blade geometry model and the coordinates of each node (X1, Y1, Z1) at this time; if it does not converge, repeat steps 3 to 7 until the hydrodynamic performance calculation results converge.

[0039] Step 8: For the blade geometry with converged hydrodynamic performance calculation results obtained in step 7, pre-deformation processing is performed using the Cartesian coordinates of the nodes corresponding to the initial metal propeller geometry in step 1, that is, the node coordinates (2X0-X1, 2Y0-Y1, 2Z0-Z1) are taken to construct the radius profiles, guide edges, and trailing edges of each section of the pre-deformed blade, and establish a pre-deformed blade geometry model.

[0040] Step 9: Repeat steps 1 to 6 to obtain the geometry of the composite propeller after the hydrodynamic performance calculation results converge. This is the geometry of the pre-deformed composite propeller in working state. Compare the hydrodynamic performance of the working blade geometry with the hydrodynamic performance of the initial metal propeller. If the hydrodynamic performance requirements are met, a composite propeller that meets the strength requirements and hydrodynamic requirements is obtained. If not, the layup scheme, especially the layup angle, needs to be adjusted in step 5.

Claims

1. A pre-deformation design method for a metal-lined composite propeller, characterized in that: The metal blade geometry model is used as the design input and the following steps are taken to achieve it: Step 1: Extract the blade geometry pressure surface and suction surface sheet models in the 3D modeling software and import them into the ACP module of the ANSYSWORKBENCH platform; Step 2: In the ACP (Pre) submodule, complete the definition of metal and composite properties, finite element meshing of the blade pressure and suction surfaces, and definition of the blade composite layer. When defining the composite layer, create different Stackups and Sub Laminates to establish the finite element model of the blade composite laminate and metal liner, and pass the mesh, geometry, material properties, and composite material definition defined in the ACP module to the Mechanical module. Step 3: Build a hydrodynamic calculation model based on the blade geometry model, use the fluid dynamics analysis module to solve the blade performance and pressure distribution, and pass the calculation results to the Mechanical module; Step 4: Add constraints to the blade finite element model in the Mechanical module, load the blade surface pressure distribution, obtain the blade deformation in all directions, and output the Cartesian coordinates (X0, Y0, Z0) of each characteristic node of the blade and the deformation result (U X ,U Y ,U Z ), and obtain the Cartesian coordinates of each node after deformation (X0+U X , Y0+U Y , Z0+U Z ); Step 5: In ACP (Post), select the failure criterion and perform failure evaluation on each ply unit of the blade to determine whether the strength requirements are met. If not, return to the ACP (Pre) module to adjust the composite material plies, including ply thickness and ply angle, until the strength requirements are met. Step 6: Based on the data obtained in step 4, reconstruct the profiles of each radius of the blade to obtain a geometric model of the deformed composite blade; Step 7: Construct a hydrodynamic calculation model based on the deformed blade geometry model, use the fluid dynamic analysis module to solve the blade performance and pressure distribution, and perform convergence judgment on the hydrodynamic performance calculation results. If converged, output the blade geometry model at this time and the coordinates of each node (X1, Y1, Z1); if not converged, repeat steps 3 to 7 until the hydrodynamic performance calculation results converge; Step 8: Based on the blade geometry obtained in step 7 and the initial metal blade geometry in step 1, the Cartesian coordinates of the corresponding nodes are used to perform pre-deformation processing, that is, the node coordinates (2X0-X1, 2Y0-Y1, 2Z0-Z1) are taken to construct a pre-deformed blade geometry model, which is the natural state geometry of the pre-deformed blade; Step 9: Based on the pre-deformed blade geometry obtained in step 8, repeat steps 1 to 7 to obtain the working state geometry of the pre-deformed composite propeller after the hydrodynamic performance calculation results converge; Step 10: Assess the hydrodynamic efficiency of the composite propeller in working state obtained in step 9. If the hydrodynamic performance requirements are met, output the composite propeller layup plan and its natural state geometry value; If the hydrodynamic performance requirements are not met, the ply thickness and ply angle are adjusted in step five until the specified hydrodynamic performance requirements are met.

2. The pre-deformation design method for a metal-lined composite propeller according to claim 1, characterized in that: In step 2: the layer material loads the upstream material property information; Fabrics defines the material and thickness of the single-layer board, with a thickness of 0.3mm, and defines the aluminum alloy metal lining with a thickness of 5mm; Stackups defines the information of the multi-layer board, including the stacking order and symmetry rules of the single-layer board, and the angle of each single-layer board; Sub Laminates defines the sub-laminate information, including the stacking order and symmetry rules of the single-layer board and the multi-layer board; the multi-layer board laying angle is set to [30° / 30° / 0° / 0° / -30°]s, and different sub-laminates are used to lay each area of ​​the blade. According to the thickness change of the original metal blade, the blade is divided into 4 areas, namely 120 layers in the root section, two middle sections: 120 layers-80 layers gradient and 80 layers-60 layers gradient, and 60 layers in the tip section. Each area has a 5mm aluminum alloy lining layer.

3. The pre-deformation design method for a metal lined composite propeller according to claim 2, characterized in that: In step 2: use Element Sets to define the blade regions; Edge Sets to define the boundaries of the blade regions; Rosettes to define the form of the laying coordinate system; Oriented Selection Sets to define the laying reference point and laminate laying direction for the selected region, and select the laying coordinate system.

4. The pre-deformation design method for a metal-lined composite propeller according to claim 3, characterized in that: In step 2: Use Modeling Groups to add sub-layer materials, angles, and number of layers to the selected Oriented Selection Sets.

5. The pre-deformation design method for a metal-lined composite propeller according to claim 1, characterized in that: In step five: select the Caiwu failure criterion, perform failure evaluation on each ply unit of the composite blade, and determine whether it meets the strength requirements. When the thickness of the aluminum alloy lining is 5 mm, there is an area where the inverse reserve factor is greater than 1 after judgment using the Caiwu failure criterion, that is, some blade units are damaged. Therefore, it is necessary to return to step two and adjust the ply structure in the Pre module of ACP. The thickness of the aluminum alloy lining is increased to 8 mm. After updating the blade finite element model information in step four, the maximum value of the inverse reserve factor of the blade unit obtained in step five is less than 1, which meets the strength requirements of the Caiwu failure criterion.

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