Design method of aluminum alloy engine cover

Abstract

The invention provides an aluminum alloy engine hood design method which comprises the following steps: S10, performing simulation calculation on five analysis working conditions, namely a rear edge beam bending working condition, a side edge beam bending working condition, a corner point bending working condition, a torsion working condition and a lateral bending working condition, of an inner plate of an aluminum alloy engine hood to obtain rigidity values of the five analysis working conditions; s20, establishing an initial model of the inner plate based on design boundary conditions, wherein the middle part of the initial model of the inner plate is completely filled with a shell unit; s30, establishing a topological optimization scheme for the initial model of the inner plate to obtain a topological model; s40, after the topological model is interpreted, an initial model with the size optimized is obtained, a size optimization scheme is established, size optimization is conducted, and a final optimized structure model is obtained; and S50, performing rigidity calculation on the final optimization structure model to obtain rigidity values of the optimized inner plate under the five analysis working conditions.

Description

Technical Field

[0001] The present invention relates to the technical field of structural optimization, and in particular to a design method for an aluminum alloy engine hood. Background Art

[0002] The main approaches to lightweighting vehicles include material and structural lightweighting. Aluminum alloy is the preferred material for lightweighting vehicles, and is currently used in aluminum alloy doors and hoods in new energy vehicles. The structural design of aluminum alloy hoods often relies on the design experience of steel hoods, primarily replacing steel with aluminum to achieve weight reduction through the replacement of lightweight materials. However, structural weight reduction is not based on the characteristics of aluminum alloy materials. As a result, certain stiffness indicators of the designed hoods sometimes exceed the target requirements. In most cases, further analysis and treatment are rarely performed. This unreasonable design with excessive stiffness redundancy increases the weight and cost of the hood. Therefore, a design method for aluminum alloy hoods that can achieve lightweighting is needed. Summary of the Invention

[0003] The present invention provides a design method for an aluminum alloy engine hood to solve the problem of rigidity redundancy of the aluminum alloy engine hood in the prior art.

[0004] In order to solve the above problems, the present invention provides an aluminum alloy hood design method, including: S10: performing simulation calculations on the inner panel of the aluminum alloy hood under five analysis conditions, namely, rear side beam bending condition, side beam bending condition, corner bending condition, torsion condition and lateral bending condition, to obtain stiffness values ​​of the five analysis conditions; S20: establishing an initial model of the inner panel based on the design boundary conditions, and the middle part of the initial model of the inner panel is completely filled with shell elements; S30: establishing a topology optimization scheme for the initial model of the inner panel to obtain a post-topology model; S40: interpreting the post-topology model to obtain a size-optimized initial model, establishing a size optimization scheme, performing size optimization, and obtaining a final optimized structural model; S50: performing stiffness calculation on the final optimized structural model to obtain the stiffness values ​​of the optimized inner panel under the five analysis conditions.

[0005] Furthermore, in S10, the inner plate is modeled using shell elements, and the inner plate is an aluminum alloy plate.

[0006] Furthermore, in S10, the boundary conditions used in the calculation of the bending condition of the rear side beam are to constrain the translational degrees of freedom in the X, Y, and Z directions at the hinge installation point where the inner panel is connected to the vehicle body, to constrain the translational degrees of freedom in the Z direction at the installation point of the secondary lock of the inner panel, to constrain the translational degrees of freedom in the Y and Z directions at the lock position of the inner panel, and to apply a load of 100N along the Z direction at the symmetrical position of the hinge installation point.

[0007] Furthermore, in S10, the boundary conditions used in the calculation of the side beam bending working condition are to constrain the translational degrees of freedom in the X, Y, and Z directions at the hinge mounting point where the inner panel is connected to the vehicle body, to constrain the translational degrees of freedom in the Z direction at the mounting point of the secondary lock of the inner panel, to constrain the translational degrees of freedom in the Y and Z directions at the lock position of the inner panel, and to apply a load of 100N along the Z direction at the middle position between the left hinge mounting point of the inner panel and the left secondary lock.

[0008] Furthermore, in S10, the boundary conditions used in the calculation of the corner bending working condition are to constrain the translational degrees of freedom in the X, Y, and Z directions at the hinge installation point connected to the vehicle body, constrain the translational degrees of freedom in the Z direction at the installation point of the upper left secondary lock of the inner panel, constrain the translational degrees of freedom in the Y and Z directions at the lock position of the inner panel, and apply a load of 100N along the Z direction at the installation point of the right secondary lock of the inner panel.

[0009] Furthermore, in S10, the boundary conditions used in the calculation of the torsional working condition are to constrain the translational degrees of freedom in the X, Y, and Z directions at the hinge installation point where the inner panel is connected to the vehicle body, to constrain the translational degrees of freedom in the Z direction at the installation point of the right secondary lock of the inner panel, and to apply a load of 100N along the -Z direction at the installation point of the left secondary lock of the inner panel.

[0010] Furthermore, in S10, the boundary conditions used in the calculation of the lateral bending working condition are to constrain the translational degrees of freedom in the X, Y, and Z directions at the hinge installation point where the inner panel is connected to the vehicle body, to constrain the translational degrees of freedom in the Z direction at the installation point of the secondary lock of the inner panel, to constrain the translational degrees of freedom in the Y and Z directions at the locking position of the inner panel, and to apply a load of 100N along the Y direction at the locking position of the inner panel.

[0011] Furthermore, in S20 , an initial model is established after conceptual design of the inner panel, and the initial model is a shell model.

[0012] Furthermore, in S30, the topology optimization scheme includes a first design variable, a constraint condition, and a first target response. The first design variable is the filling area in the middle part of the initial model of the inner plate; the constraint condition is a value whose volume fraction is less than 1; the first target response is stiffness maximization or strain energy minimization; the topology optimization scheme includes setting a weighted coefficient ratio for 5 analysis conditions, and the first target response stiffness maximization is set according to the stiffness weighted coefficient ratio of the 5 analysis conditions.

[0013] Furthermore, in S30, the stiffness weighting coefficient ratio represents the importance of different analysis conditions, and is calculated as the ratio of the stiffness target values ​​of the five analysis conditions, namely, the rear beam bending condition, the side beam bending condition, the corner bending condition, the torsion condition, and the lateral bending condition, to the stiffness value calculated by the initial model.

[0014] Furthermore, in S40, the size optimization scheme includes a second design variable, a constraint function, and a second target response. The second design variable is the plate thickness of each component of the inner panel; the constraint function is that the stiffness value under the five analysis conditions is ≥ the stiffness target value; and the second target response is mass minimization.

[0015] Furthermore, in S40, the constraint function is that the optimized stiffness values ​​of the five analysis conditions of rear beam bending, side beam bending, corner bending, torsion and lateral bending are not less than the stiffness target values ​​of the corresponding conditions.

[0016] By applying the technical solution of the present invention, a method for designing an aluminum alloy hood is provided, comprising: S10: performing simulation calculations on the inner panel of the aluminum alloy hood under five analysis conditions, namely, rear side beam bending condition, side beam bending condition, corner bending condition, torsion condition and lateral bending condition, to obtain stiffness values ​​of the five analysis conditions; S20: establishing an initial model of the inner panel based on the design boundary conditions, and completely filling the middle part of the initial model of the inner panel with shell elements; S30: establishing a topology optimization scheme for the initial model of the inner panel to obtain a post-topology model; S40: interpreting the post-topology model to obtain a size-optimized initial model, establishing a size optimization scheme, performing size optimization, and obtaining a final optimized structural model; S50: performing stiffness calculations on the final optimized structural model to obtain the stiffness values ​​of the optimized inner panel under the five analysis conditions. By adopting this scheme, the five working conditions of the inner panel are analyzed to obtain the stiffness values ​​of the inner panel under the five working conditions. Based on the initial model, topology optimization is performed to establish the post-topology model. The post-topology model is optimized to obtain the final optimized structural model. The optimized model can remove the redundancy of stiffness and obtain a lightweight inner panel. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0018] Figure 1 A flow chart showing a method for designing an aluminum alloy hood according to an embodiment of the present invention is shown;

[0019] Figure 2 A schematic structural diagram of an aluminum alloy engine cover provided by another embodiment of the present invention is shown;

[0020] Figure 3 Shown Figure 2 A schematic diagram of the structure of the inner panel of the aluminum alloy hood;

[0021] Figure 4 Shown Figure 2 Schematic diagram of the structure of the outer panel of the aluminum alloy hood.

[0022] The above drawings include the following reference numerals:

[0023] 1. Inner panel;

[0024] 10. Inner frame;

[0025] 11. Plate body;

[0026] 111. First reduction group;

[0027] 1111, first weight-reducing hole;

[0028] 1112, second weight-reducing hole;

[0029] 112. Second reduction group;

[0030] 1121, the third weight-reducing hole;

[0031] 113. Inner plate reinforcement;

[0032] 12. Ring plate;

[0033] 121. The third reduction group;

[0034] 1211, the fourth weight-reducing hole;

[0035] 20. Outer frame;

[0036] 21. Fourth reduction group;

[0037] 211, the fifth weight-reducing hole;

[0038] 31. First side;

[0039] 32. Second side;

[0040] 2. Outer panel;

[0041] 3. First reinforcement plate;

[0042] 4. Second reinforcement plate;

[0043] 5. Outer plate support plate. DETAILED DESCRIPTION

[0044] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is in no way intended to limit the present invention and its application or use. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative work are within the scope of protection of the present invention.

[0045] like Figure 1 As shown, an embodiment of the present invention provides an aluminum alloy hood design method, including: S10: performing simulation calculations on the inner panel 1 of the aluminum alloy hood under five analysis conditions, namely, rear side beam bending condition, side beam bending condition, corner bending condition, torsion condition and lateral bending condition, to obtain stiffness values ​​of the five analysis conditions; S20: establishing an initial model of the inner panel 1 based on the design boundary conditions, and the middle part of the initial model of the inner panel 1 is completely filled with shell elements; S30: establishing a topology optimization scheme for the initial model of the inner panel 1 to obtain a post-topology model; S40: interpreting the post-topology model to obtain a size-optimized initial model, establishing a size optimization scheme, performing size optimization, and obtaining a final optimized structural model; S50: performing stiffness calculations on the final optimized structural model to obtain the stiffness values ​​of the optimized inner panel 1 under the five analysis conditions.

[0046] By adopting this scheme, the five working conditions of the inner panel 1 are analyzed to obtain the stiffness values ​​of the inner panel 1 under the five working conditions. Based on the initial model, topology optimization is performed to establish a post-topology model. The post-topology model is optimized to obtain the final optimized structural model. The optimized model can remove the redundancy of stiffness and obtain a lightweight inner panel 1.

[0047] Furthermore, in S10, the inner panel 1 is modeled using shell elements, and the inner panel 1 is an aluminum alloy plate.

[0048] The use of an aluminum alloy plate for the inner panel 1 can reduce the weight of the inner panel 1 , and the aluminum alloy plate can achieve the strength required for the inner panel 1 of the hood, thereby achieving lightweighting of the inner panel 1 .

[0049] like Figure 1 As shown, in S10, the boundary conditions used in the calculation of the bending condition of the rear side beam are to constrain the translational freedom in the X, Y, and Z directions at the hinge installation point where the inner panel 1 is connected to the vehicle body, constrain the translational freedom in the Z direction at the installation point of the secondary lock of the inner panel 1, constrain the translational freedom in the Y and Z directions at the lock position of the inner panel 1, and apply a load of 100N along the Z direction at the symmetrical position of the hinge installation point.

[0050] It can be imagined that by constraining the translational freedom and applying loads at various positions of the inner panel 1, the stiffness of the inner panel 1 under the bending condition of the rear side beam can be measured, thereby removing stiffness redundancy and performing a lightweight design for the structure of the inner panel 1.

[0051] like Figure 1As shown, in S10, the boundary conditions used in the calculation of the side beam bending working condition are to constrain the translational freedom in the X, Y, and Z directions at the hinge installation point where the inner panel 1 is connected to the vehicle body, constrain the translational freedom in the Z direction at the installation point of the secondary lock of the inner panel 1, constrain the translational freedom in the Y and Z directions at the lock position of the inner panel 1, and apply a load of 100N along the Z direction at the middle position between the left hinge installation point of the inner panel 1 and the left secondary lock.

[0052] In this way, the boundary conditions of the inner panel 1 under the side beam bending condition are set, the stiffness of the inner panel 1 under the side beam bending condition is calculated, and the stiffness redundancy is removed to achieve a lightweight design of the inner panel 1.

[0053] Furthermore, in S10, the boundary conditions used in the calculation of the corner bending working condition are to constrain the translational degrees of freedom in the X, Y, and Z directions at the hinge installation point connected to the vehicle body, constrain the translational degrees of freedom in the Z direction at the installation point of the left secondary lock on the inner panel 1, constrain the translational degrees of freedom in the Y and Z directions at the lock position of the inner panel 1, and apply a load of 100N along the Z direction at the installation point of the right secondary lock of the inner panel 1.

[0054] In this way, the boundary conditions of the inner panel 1 under the corner bending condition are set, the stiffness of the inner panel 1 under the corner bending condition is calculated, and the stiffness redundancy is removed to achieve a lightweight design of the inner panel 1.

[0055] like Figure 1 As shown, in S10, the boundary conditions used in the calculation of the torsional working condition are to constrain the translational freedom in the X, Y, and Z directions at the hinge installation point where the inner panel 1 is connected to the vehicle body, to constrain the translational freedom in the Z direction at the installation point of the right secondary lock of the inner panel 1, and to apply a load of 100N along the -Z direction at the installation point of the left secondary lock of the inner panel 1.

[0056] In this way, the boundary conditions of the inner panel 1 under the torsion condition are set, the stiffness of the inner panel 1 under the torsion condition is calculated, and the stiffness redundancy is removed to achieve a lightweight design of the inner panel 1.

[0057] like Figure 1 As shown, in S10, the boundary conditions used in the calculation of the lateral bending working condition are to constrain the translational freedom in the X, Y, and Z directions at the hinge installation point where the inner panel 1 is connected to the vehicle body, to constrain the translational freedom in the Z direction at the installation point of the secondary lock of the inner panel 1, to constrain the translational freedom in the Y and Z directions at the lock position of the inner panel 1, and to apply a load of 100N along the Y direction at the lock position of the inner panel 1.

[0058] In this way, the boundary conditions of the inner panel 1 under the lateral bending condition are set, the stiffness of the inner panel 1 under the lateral bending condition is calculated, and the stiffness redundancy is removed to achieve a lightweight design of the inner panel 1.

[0059] Furthermore, in S20 , an initial model is established after conceptual design of the inner panel 1 , and the initial model is a shell model.

[0060] The shell model is an integrated structure when subjected to stress, and can accurately simulate the stiffness of the inner panel 1 during the stress process, thereby accurately optimizing the inner panel 1.

[0061] In a specific embodiment of the present invention, in S30, the topology optimization scheme includes a first design variable, a constraint condition, and a first target response, wherein the first design variable is the filling area in the middle part of the initial model of the inner panel 1; the constraint condition is a value whose volume fraction is less than 1; the first target response is stiffness maximization or strain energy minimization; the topology optimization scheme includes setting a weighted coefficient ratio for 5 analysis conditions, and the first target response stiffness maximization is set according to the stiffness weighted coefficient ratio of the 5 analysis conditions.

[0062] The topology optimization model is obtained by performing topology optimization on the initial model according to the three values ​​of the first design variable, the constraint condition and the first target response.

[0063] Furthermore, in S30, the stiffness weighting coefficient ratio represents the importance of different analysis conditions, and is calculated as the ratio of the stiffness target values ​​of the five analysis conditions, namely, the rear beam bending condition, the side beam bending condition, the corner bending condition, the torsion condition, and the lateral bending condition, to the stiffness value calculated by the initial model.

[0064] It can be understood that the stiffness weighted coefficient ratio is calculated to perform topology optimization on the initial model so that the topology optimization model obtained after topology optimization can meet the analysis results of the five analysis conditions.

[0065] Furthermore, in S40, the size optimization scheme includes a second design variable, a constraint function and a second target response. The second design variable is the plate thickness of each component of the inner panel 1; the constraint function is that the stiffness value under 5 analysis conditions is ≥ the stiffness target value; and the second target response is mass minimization.

[0066] By setting the stiffness value under five analysis conditions ≥ the stiffness target value, the dimensions of each position of the topology optimization model are calculated, the stiffness redundancy is removed, and the lightweighting of the inner panel 1 is achieved.

[0067] Furthermore, in S40, the constraint function is that the optimized stiffness values ​​of the five analysis conditions of rear beam bending, side beam bending, corner bending, torsion and lateral bending are not less than the stiffness target values ​​of the corresponding conditions.

[0068] like Figures 2 to 4 As shown, another embodiment of the present invention provides an aluminum alloy engine hood, which applies the above-mentioned engine hood design method, including:

[0069] Inner plate 1, inner plate 1 is divided into two symmetrical parts by a preset first symmetry plane. Inner plate 1 includes an outer frame 20 and an inner frame 10 disposed within outer frame 20. Inner frame 10 includes a plate body 11 and an annular plate 12. Plate body 11 is located on the side of the inner surface facing away from the outer surface. Plate body 11 is provided with two groups of first weight-reducing groups 111 symmetrical with respect to the first symmetry plane. First weight-reducing groups 111 include multiple weight-reducing holes. Annular plate 12 is disposed around plate body 11. The inner circumference of annular plate 12 is connected to plate body 11, and the outer circumference of annular plate 12 is connected to outer frame 20. The thickness of inner plate 1 is 0.8-1.2 mm.

[0070] The outer panel 2 is provided above the inner panel 1 and is used to protect the inner panel 1. The thickness of the outer panel 2 is 0.8-1.2 mm.

[0071] With this solution, the first reduction group 111 achieves lightweighting of the inner panel 1, removing redundant rigidity from the inner panel 1, and reducing the weight of the inner panel 1 while maintaining its rigidity. The outer panel 2 is positioned over the inner panel 1 to protect it.

[0072] In a specific embodiment of the present invention, during the structural optimization of inner panel 1, the thickness of inner panel 1 was varied between 0.8 and 1.2 mm, with the thickness of inner panel 1 increasing by 0.1 mm at a time for simulation calculations. During the structural optimization of outer panel 2, the thickness of outer panel 2 was varied between 0.8 and 1.2 mm, with the thickness of outer panel 2 increasing by 0.1 mm at a time for simulation calculations.

[0073] like Figure 3 As shown, the first weight reduction group 111 includes at least two first weight reduction holes 1111 and one second weight reduction hole 1112. The edge of the first weight reduction hole 1111 is arc-shaped, and the second weight reduction hole 1112 is a parallelogram. The first weight reduction hole 1111 is arranged on the edge of the plate body 11, and the second weight reduction hole 1112 is arranged on the side of the first weight reduction hole 1111 close to the first symmetry plane.

[0074] With this arrangement, the edges of first lightening holes 1111 are curved, preventing stress concentration in the periphery of first lightening holes 1111 when inner panel 1 is subjected to external forces. Second lightening holes 1112 are parallelogram-shaped, with all four corners curved, preventing stress concentration in the periphery of second lightening holes 1112 when inner panel 1 is subjected to external forces. The arrangement of first and second lightening holes 1111, 1112, achieves lightweighting of inner panel 1, eliminates redundant stiffness, and reduces weight while maintaining stiffness.

[0075] like Figure 3As shown, the plate body 11 is provided with two groups of second weight-reducing groups 112 symmetrical with respect to the first symmetry plane. The second weight-reducing groups 112 include at least two third weight-reducing holes 1121 . The third weight-reducing holes 1121 are provided on one side of the second weight-reducing holes 1112 close to the first symmetry plane.

[0076] Thus, the two second weight-reducing groups 112 are used to reduce the weight of the inner panel 1, thereby achieving lightweighting of the inner panel 1 while maintaining the rigidity of the inner panel 1. The second weight-reducing group includes at least two third weight-reducing holes 1121, each of which has rounded corners to prevent stress concentration when the inner panel 1 is subjected to external forces.

[0077] Furthermore, if Figure 3 As shown, the aluminum alloy hood has a second symmetry plane perpendicular to the first symmetry plane, the second weight reduction group 112 includes two third weight reduction holes 1121, the two third weight reduction holes 1121 are symmetrically arranged along the second symmetry plane, and the second weight reduction holes 1112 are symmetrical along the second symmetry plane.

[0078] In this arrangement, the two third weight-reducing holes 1121 are symmetrically arranged along the second symmetry plane, and the second weight-reducing holes 1112 are symmetrical along the second symmetry plane, so that the shape of the inner plate 1 is more uniform, and the stress distribution of the inner plate 1 under the action of external force is more uniform, and it is not easy to be damaged.

[0079] like Figure 3 As shown, an inner plate reinforcing rib 113 is formed between any two adjacent ones of the first weight-reducing hole 1111 , the second weight-reducing hole 1112 and the third weight-reducing hole 1121 , and there are multiple inner plate reinforcing ribs 113 .

[0080] With this arrangement, an inner plate reinforcement rib 113 is formed between any two adjacent weight-reducing holes among the first, second, and third weight-reducing holes 1111, 1112, and 1121, providing support. This rib ensures the rigidity of the inner plate 1 when subjected to external forces, while also reducing the weight of the inner plate 1.

[0081] like Figure 3 As shown, the annular plate 12 is provided with two third weight-reducing groups 121 symmetrically arranged relative to the first symmetry plane. The third weight-reducing groups include a plurality of fourth weight-reducing holes 1211 , which are arranged along the circumference of the annular plate 12 .

[0082] Thus, the third weight-reducing group 121 is used to reduce the weight of the inner panel 1, thereby achieving lightweight while maintaining rigidity and eliminating redundant rigidity. The third weight-reducing group includes a plurality of fourth weight-reducing holes 1211, which are arranged along the circumference of the annular plate 12, making the shape of the inner panel 1 more uniform and less susceptible to stress concentration when subjected to external forces.

[0083] In a specific embodiment of the present invention, most of the fourth weight-reducing holes 1211 are disposed on two opposite sides of the annular plate 12 , and the other fourth weight-reducing holes 1211 are disposed on the other two sides of the annular plate 12 .

[0084] like Figure 3 As shown, the outer frame 20 is provided with two groups of fourth weight-reducing groups 21 symmetrically arranged relative to the first symmetry plane. The fourth weight-reducing groups 21 include a plurality of fifth weight-reducing holes 211 , and the plurality of fifth weight-reducing holes 211 are arranged along the circumference of the outer frame 20 .

[0085] In this way, the fourth weight-reducing group 21 includes a plurality of fifth weight-reducing holes 211, and the plurality of fifth weight-reducing holes 211 are arranged along the circumference of the outer frame 20, thereby achieving lightweighting of the outer frame 20, so that the inner panel 1 eliminates the redundancy of stiffness while ensuring the structural strength, thereby achieving lightweighting of the inner panel 1.

[0086] like Figure 2 As shown, the inner panel 1 has an arc-shaped first side 31, and the aluminum alloy hood also includes two first reinforcing plates 3, which are arranged at both ends of the first side 31. The first reinforcing plates 3 are used to reinforce the inner panel 1, and the thickness of the first reinforcing plates 3 is 1.6-2.5 mm.

[0087] With this arrangement, the first reinforcing plates 3 are positioned at both ends of the first side 31, reinforcing the inner panel 1. The first side 31 is connected to the hinges at both ends, which act as a connection when the aluminum alloy hood is opened and closed. Therefore, the first reinforcing plates 3 reinforce the inner panel 1, preventing damage to the inner panel 1 from the tension of the hinges.

[0088] In a specific embodiment of the present invention, during the optimization of the first reinforcing plate 3, the thickness of the first reinforcing plate 3 varies between 1.6 and 2.5 mm, and the thickness of the first reinforcing plate 3 is increased by 0.1 mm each time for simulation calculation, thereby obtaining the optimal value of the first reinforcing plate 3.

[0089] like Figure 2 As shown, the aluminum alloy hood also includes a second reinforcing plate 4, the inner plate 1 has a first side 31 and a second side 32 arranged opposite to each other, the second reinforcing plate 4 is arranged at the edge of the outer frame 20 close to the second side 32, the second reinforcing plate 4 is used to reinforce the inner plate 1, and the thickness of the second reinforcing plate 4 is 1.6-2.5mm.

[0090] In this way, the second reinforcing plate 4 reinforces the edge of the outer frame 20 close to the second side 32. During the opening and closing of the aluminum alloy hood, a fixing lock is installed on the edge of the outer frame 20 close to the second side 32. The second reinforcing plate 4 reinforces the inner panel 1 to prevent the inner panel 1 from being damaged by the tensile force during the operation of the fixing lock.

[0091] In a specific embodiment of the present invention, during the optimization of the second reinforcing plate 4, the thickness of the second reinforcing plate 4 varies between 1.6 and 2.5 mm, and the thickness of the second reinforcing plate 4 is increased by 0.1 mm each time for simulation calculation, thereby obtaining the optimal value of the second reinforcing plate 4.

[0092] like Figure 2 As shown, the aluminum alloy hood also includes an outer panel support plate 5, the inner panel 1 has a first side edge 31 and a second side edge 32 arranged opposite to each other, the outer panel support plate 5 is arranged on the edge of the outer frame 20 close to the second side edge 32, the outer panel support plate 5 is connected to the annular plate 12, the outer panel support plate 5 is used to support the outer panel 2, and the thickness of the outer panel support plate 5 is 0.8-2.5mm.

[0093] With this arrangement, the outer panel support plate 5 reinforces the edge of the outer frame 20 close to the second side edge 32 , and when the aluminum alloy hood is in operation, the outer panel support plate 5 supports the outer panel 2 .

[0094] In a specific embodiment of the present invention, during the optimization of the outer panel support plate 5, the thickness of the outer panel support plate 5 varies between 0.8 and 2.5 mm, and the thickness of the outer panel support plate 5 is increased by 0.1 mm each time for simulation calculation, thereby obtaining the optimal value of the outer panel support plate 5.

[0095] The advantages of the present invention are:

[0096] 1. The solution of the present invention optimizes the structure of the aluminum alloy hood, thereby achieving overall lightweighting of the aluminum alloy hood. This eliminates redundant rigidity while maintaining the structural strength of the aluminum alloy hood.

[0097] 2. The thickness of the inner panel 1, outer panel 2, first reinforcing panel 3, second reinforcing panel 4 and outer panel support panel 5 is increased by 0.1 mm each time for simulation calculation to obtain the optimal thickness values ​​of the inner panel 1, outer panel 2, first reinforcing panel 3, second reinforcing panel 4 and outer panel support panel 5.

[0098] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

[0099] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0100] Unless otherwise specifically stated, the relative arrangement of the parts and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present invention. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to actual proportional relationships. The technology, methods and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be considered as a part of the specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of the exemplary embodiments can have different values. It should be noted that similar numbers and letters represent similar items in the following drawings, and therefore, once an item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0101] In the description of the present invention, it should be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "horizontal, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention; the directional words "inside and outside" refer to the inside and outside relative to the outline of each component itself.

[0102] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used herein to describe the spatial positional relationship of a device or feature to other devices or features as shown in the figures. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figures. For example, if the device in the drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0103] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

Claims

1. A method for designing an aluminum alloy hood, characterized in that: include: S10: performing simulation calculations on the inner panel (1) of the aluminum alloy engine hood under five analysis conditions, namely, a rear beam bending condition, a side beam bending condition, a corner bending condition, a torsion condition, and a lateral bending condition, to obtain stiffness values ​​of the five analysis conditions; S20: establishing an initial model of the inner plate (1) based on the design boundary conditions, wherein the middle part of the initial model of the inner plate (1) is completely filled with shell elements; S30: establishing a topology optimization scheme for the initial model of the inner plate (1) to obtain a topology model; S40: interpreting the post-topological model to obtain an initial model for size optimization, establishing a size optimization plan, performing size optimization, and obtaining a final optimized structural model; S50: performing stiffness calculation on the final optimized structural model to obtain stiffness values ​​of the optimized inner panel (1) under the five analysis conditions.

2. The aluminum alloy hood design method according to claim 1, characterized in that: In S10, the inner plate (1) is modeled using shell elements, and the inner plate (1) is an aluminum alloy plate.

3. The aluminum alloy engine hood design method according to claim 1, characterized in that: In S10, the boundary conditions used in the calculation of the bending condition of the rear side beam are: constraining the translational degrees of freedom in the X, Y and Z directions at the hinge installation point where the inner panel (1) is connected to the vehicle body, constraining the translational degrees of freedom in the Z direction at the installation point of the secondary lock of the inner panel (1), constraining the translational degrees of freedom in the Y and Z directions at the lock position of the inner panel (1), and applying a load of 100N along the Z direction at the symmetrical position of the hinge installation point.

4. The aluminum alloy engine hood design method according to claim 1, characterized in that: In S10, the boundary conditions used in the calculation of the side beam bending condition are: constraining the translational freedom in the X, Y and Z directions at the hinge installation point where the inner panel (1) is connected to the vehicle body, constraining the translational freedom in the Z direction at the installation point of the secondary lock of the inner panel (1), constraining the translational freedom in the Y and Z directions at the lock position of the inner panel (1), and applying a load of 100N along the Z direction at the middle position between the left hinge installation point and the left secondary lock of the inner panel (1).

5. The aluminum alloy engine hood design method according to claim 1, characterized in that: In S10, the boundary conditions used in the calculation of the corner bending working condition are: constraining the translational freedom in the X, Y and Z directions at the hinge installation point connected to the vehicle body, constraining the translational freedom in the Z direction at the installation point of the left secondary lock on the inner panel (1), constraining the translational freedom in the Y and Z directions at the lock position of the inner panel (1), and applying a load of 100N along the Z direction at the installation point of the right secondary lock of the inner panel (1).

6. The aluminum alloy engine hood design method according to claim 1, characterized in that: In S10, the boundary conditions used in the calculation of the torsion working condition are to constrain the translational freedom in the X, Y and Z directions at the hinge installation point where the inner panel (1) is connected to the vehicle body, to constrain the translational freedom in the Z direction at the installation point of the right secondary lock of the inner panel (1), and to apply a load of 100N in the -Z direction at the installation point of the left secondary lock of the inner panel (1).

7. The aluminum alloy engine hood design method according to claim 1, characterized in that: In S10, the boundary conditions used in the calculation of the lateral bending working condition are: constraining the translational degrees of freedom in the X, Y and Z directions at the hinge installation point where the inner panel (1) is connected to the vehicle body, constraining the translational degrees of freedom in the Z direction at the installation point of the secondary lock of the inner panel (1), constraining the translational degrees of freedom in the Y and Z directions at the locking position of the inner panel (1), and applying a load of 100N along the Y direction at the locking position of the inner panel (1).

8. The aluminum alloy engine hood design method according to claim 1, characterized in that: In S20, the initial model is established after conceptual design of the inner panel (1), and the initial model is a shell model.

9. The aluminum alloy engine hood design method according to claim 1, characterized in that: In S30, the topology optimization scheme includes a first design variable, a constraint condition, and a first target response, wherein the first design variable is a filling area in the middle part of the initial model of the inner plate (1); the constraint condition is a value whose volume fraction is less than 1; and the first target response is maximizing stiffness or minimizing strain energy; The topology optimization scheme includes setting weighted coefficient ratios for the five analysis conditions, and the first target response stiffness maximization is set according to the stiffness weighted coefficient ratios of the five analysis conditions.

10. The aluminum alloy engine hood design method according to claim 9, characterized in that: In S30, the stiffness weighting coefficient ratio represents the importance of different analysis conditions, and is calculated by the ratio of the stiffness target values ​​of the five analysis conditions, namely, the rear beam bending condition, the side beam bending condition, the corner bending condition, the torsion condition and the lateral bending condition, to the stiffness value calculated by the initial model.

11. The aluminum alloy engine hood design method according to claim 1, characterized in that: In S40, the size optimization scheme includes a second design variable, a constraint function and a second target response, wherein the second design variable is the plate thickness of each component of the inner panel (1); the constraint function is that the stiffness value under the five analysis conditions is greater than or equal to the stiffness target value; and the second target response is mass minimization.

12. The aluminum alloy engine hood design method according to claim 1, characterized in that: In S40, the constraint function is that the optimized stiffness values ​​of the five analysis conditions of rear beam bending, side beam bending, corner bending, torsion and lateral bending are not less than the stiffness target values ​​of the corresponding conditions.

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