Design method of hub for aircraft tire test

Abstract

The invention relates to the technical field of aircraft design, and particularly discloses a design method of a hub for an aircraft tire test, and the method comprises the steps: building a finite element model of the hub; configuring parameters on the finite element model; calculating the finite element model according to the parameters to obtain the maximum stress value and the displacement value of the finite element model under the radial load and the lateral load; establishing a finite element model of an axisymmetric plane unit for the cross section of the hub, and designing based on a topological optimization result to obtain a primarily optimized parameterized geometric model; and 5 key parameters including the rim thickness are selected based on the initially optimized parameterized geometric model, a global optimization and local optimization combined algorithm is used, the maximum displacement value under the lateral load is used as a constraint condition, parameter optimization is carried out, and a final optimization model of the hub is obtained. By means of the method, the light weight of the hub is kept, and meanwhile small deformation and high strength of the hub are kept.

Description

Technical Field

[0001] The invention relates to the technical field of aircraft design, in particular to a design method of a hub for aviation tire testing. Background Art

[0002] Aircraft wheels are the main supporting structure of aircraft on the road surface, used to bear various static and dynamic loads from the ground. Aircraft wheels are divided into two categories according to whether they have brake devices or not: brake wheels and brakeless wheels. Brakeless wheels mainly include tires and hubs. The structural forms of hubs can be summarized into four types: single-width plate, double-width plate, split type and combined type. At present, the split structure is more commonly used in aircraft wheels. In the design process of the hub for aviation tire testing, in order to meet various harsh test conditions, higher structural strength and smaller deformation are required, but at the same time, it may bring more material usage, larger mass and moment of inertia. Therefore, the design of the hub needs to find a balance between higher structural strength and deformation stiffness, and lower mass. Summary of the invention

[0003] The object of the present invention is to provide a design method for a hub for aviation tire testing, so that the hub can be kept lightweight while maintaining small deformation and high strength.

[0004] In order to achieve the above-mentioned object, the present invention provides a design method for a hub for testing aircraft tires, wherein the aircraft tire is mounted on the outer periphery of the hub, the hub is a split hub and is assembled by bolts, and the hub is connected to a tooling shaft of a test bench by a bearing, comprising:

[0005] Adapting the wheel hub according to the specifications of the aircraft tire, and establishing a finite element model of the wheel hub;

[0006] Configuring the material of the wheel hub, the inflation pressure of the aircraft tire, and the radial load and lateral load parameters of the wheel hub on the finite element model;

[0007] Calculating the finite element model according to the parameters to obtain the maximum stress value and displacement value of the finite element model under radial load and lateral load, and judging whether there is sufficient optimization space for the structure;

[0008] A finite element model of an axisymmetric plane unit is established for the cross section of the hub, topological optimization is performed on the finite element model of the cross section of the hub under radial load to obtain a calculation result with symmetry, and a primary optimized parameterized geometric model is designed based on the topological optimization result;

[0009] Based on the parametric geometric model of the initial optimization, five key parameters including the rim thickness are selected, and a combined global optimization and local optimization algorithm is used to perform parameter optimization with the maximum displacement value under lateral load as a constraint condition to obtain the final optimized model of the hub.

[0010] In some embodiments, the parameters configured by the finite element model further include a preload force parameter applied by the bolt and a friction coefficient of the contact surface of the two wheel hubs.

[0011] In some embodiments, the topology optimization includes:

[0012] An axisymmetric plane model is established for the axial section of the finite element model, and a second-order triangular unit with a size of 2 mm is used for meshing to form a mesh unit;

[0013] The SIMP topology optimization algorithm is used to retain the mesh elements that affect the stress of the hub structure, and the optimization target is defined as a 40% volume reduction. The topology optimization calculation result is used as the first plane model.

[0014] In some embodiments, the parameterized geometric model designed based on the topology optimization result to obtain the initial optimization includes:

[0015] The jagged edges of the first plane model are smoothed, and according to the actual installation scenario and processing difficulty of the wheel hub, grid units at the bolt fastening positions are added to obtain a second plane model;

[0016] A three-dimensional model is generated based on the rotation of the second plane model, and a primary optimization model is obtained after bolt mounting holes are added.

[0017] In some embodiments, the parameter optimization includes:

[0018] Setting weight-reducing holes at the web positions of the primary optimization model, and obtaining the thickness of the hub, the length of the bolt holes, the spacing of the bearing seats, the thickness of the web and the angle of the weight-reducing holes as design parameters;

[0019] The maximum displacement value of the model is used as a constraint condition to ensure that the stiffness of the hub meets the requirements and the design parameters corresponding to the minimum volume of the hub are met.

[0020] In some embodiments, the parameter optimization further comprises:

[0021] The multi-island genetic algorithm is used to locate the area where the maximum displacement value is located in the design parameter space, and then the nonlinear sequence quadratic programming method is used to accurately optimize the area, and finally the parameter optimization result is obtained.

[0022] In some embodiments, the design parameters of the hub thickness, bolt hole length, bearing seat spacing, and web thickness are accurate to 0.01 mm.

[0023] In some embodiments, the maximum displacement value of the wheel hub is used as a constraint condition for parameter optimization, and the maximum displacement value of the wheel hub is 0.5-1.0 mm.

[0024] In some embodiments, the wheel hub is made of 2014-T6 aluminum alloy.

[0025] The present invention provides a design method for a hub for aviation tire testing, which has the following beneficial effects compared with the prior art:

[0026] By establishing a finite element model of an axisymmetric plane unit for the cross section of the hub, topologically optimizing the finite element model of the cross section of the hub under radial load, a calculation result with symmetry is obtained, and a parameterized geometric model with initial optimization is designed based on the topological optimization result; weight reduction holes are added to the parameterized geometric model, and the five geometric parameters of the parameterized geometric model are parameterized optimized under lateral load, and the maximum displacement value of the hub is used as a constraint condition for parameter optimization. The parameter optimization method adopts a multi-island genetic algorithm and a nonlinear sequence quadratic programming method combined optimization strategy, and the final optimized model of the hub is obtained based on the optimized geometric parameters. The hub of the final design is kept lightweight while maintaining its small deformation and high strength. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 A schematic flow chart of a method for designing a hub for aviation tire testing provided by an embodiment of the present invention.

[0028] Figure 2 The invention is an enlarged schematic diagram of a finite element model of an axisymmetric plane unit for establishing a cross section of a hub in a design method for a hub for an aircraft tire test provided by an embodiment of the present invention.

[0029] Figure 3 A schematic diagram of the structure of an initial optimization model for a design method of a hub for aviation tire testing provided by an embodiment of the present invention.

[0030] Figure 4 A schematic structural diagram of a hub finite element model of a design method for a hub for aviation tire testing provided in an embodiment of the present invention.

[0031] Figure 5 A schematic diagram of a parametric geometric model structure for initial optimization of a hub in a design method for an aviation tire test hub provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments.

[0033] It should be understood that, in the description of the present application, the terms "upper", "lower", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. The terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated, that is, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In addition, unless otherwise specified, "multiple" means two or more.

[0034] In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0035] Figure 1 The following is a flow chart of a design method for a hub for testing aircraft tires provided in an embodiment of the present invention. Figure 1 As shown, the design method of the hub for testing aviation tires provided in the embodiment of the present invention, the aviation tire is installed on the outer periphery of the hub, the hub is a split hub and is assembled by bolts, the hub does not contain brakes and power structures, and the hub is connected to the tooling shaft of the test bench through a bearing, including the following steps:

[0036] S1. Adapt the wheel hub according to the specifications of the aircraft tire and establish a finite element model of the wheel hub;

[0037] S2. Configure the wheel hub material, the inflation pressure of the aircraft tire, and the radial load and lateral load parameters of the wheel hub on the finite element model;

[0038] S3. Calculate the finite element model according to the parameters to obtain the maximum stress value and displacement value of the finite element model under radial load and lateral load, and determine whether there is sufficient optimization space for the structure;

[0039] S4, Figure 4 This is the cross-section design effect before topology optimization, such as Figure 5In order to obtain the cross-sectional design effect after topological optimization, a finite element model of the axisymmetric plane unit is established for the cross section of the hub. The finite element model of the cross section of the hub is topologically optimized under radial load to obtain a symmetrical calculation result. The initial optimized parametric geometric model is designed based on the topological optimization result. Specifically, in the process of topological optimization, the cross section is redesigned based on the topological optimization result, the rim profile remains unchanged, and the part of the hub close to the center axis is hollowed out to form a web. The thickness of the web is taken as the measured value of the topological optimization result at this part. The bolt installation position is adjusted to a position closer to the rim surface. Since the half-rim needs to be tightened with bolts, it is impossible to completely hollow out the interior according to the topological optimization result, so the original shape is retained here. Finally, the stiffness of the hub is improved and the maximum displacement is reduced.

[0040] S5. Based on the parametric geometric model of the initial optimization, five key parameters including the rim thickness are selected, and a combined global optimization and local optimization algorithm is used. The maximum displacement value under lateral load is used as a constraint condition to perform parameter optimization and obtain the final optimized model of the hub.

[0041] Based on the above design method, the final designed wheel hub is kept lightweight while maintaining small deformation and high strength.

[0042] For example, a test wheel hub with a tire specification of 27×7.75-15 is analyzed and a geometric model is established. The wheel hub is a split-type brakeless wheel hub, and the two wheel hubs are connected by 12 high-strength bolts distributed around the circumference. The wheel hub's stiffness and strength under two extreme conditions of radial load and lateral load, and the tire parameters are shown in the following table:

[0043] Working conditions Side load(kN) Radial load(kN) <![CDATA[Tire pressure P0 (MPa)]]> Working condition 1 0 64.5 1.52 Working condition 2 13 43 1.38

[0044] Among them, when the wheel is subjected to radial load and lateral load, the ground load is transmitted to the hub through the tire. At the same time, the hub also needs to bear the air pressure load inside the tire. According to engineering experience, the load condition of the lateral load to the fixed rim side (inward) is a severe load condition for the hub. Under the action of tire pressure, the hub generates an external expansion force at the root of the rim on both sides of the tire; during radial load, the load is mainly borne by the high-strength steel wire of the tire bead, and part of the load will act on the wheel rim due to tire deformation; during lateral load, the tire deforms laterally, the lateral load acts on the unilateral wheel rim, and a pair of moments are added to the bead seat.

[0045] In one embodiment, the finite element model configuration parameters also include a preload force parameter applied by the bolt and a friction coefficient of the contact surface of the two hubs.

[0046] In one embodiment, the topology optimization of step S4 includes:

[0047] S41, establishing an axisymmetric plane model for the axial section of the finite element model, and using a second-order triangular unit with a size of 2 mm to perform mesh division to form a mesh unit;

[0048] S42. Use the SIMP topology optimization algorithm to retain the mesh elements that affect the stress of the hub structure, define the optimization target as a 40% volume reduction, and use the topology optimization calculation results as the first plane model.

[0049] In one embodiment, the parameterized geometric model designed to obtain the initial optimization based on the topology optimization result includes:

[0050] S43, smoothing the jagged edges of the first plane model, and adding grid cells at bolt fastening positions according to actual installation scenarios and processing difficulty of the wheel hub to obtain a second plane model;

[0051] S44, generating a three-dimensional model based on the rotation of the second plane model, and obtaining a primary optimization model after adding bolt mounting holes.

[0052] See also Figure 2 and 3 As shown, in one embodiment, the parameter optimization in step S5 includes:

[0053] S51, setting a weight-reducing hole at the web position of the initial optimization model, and obtaining the thickness a of the hub, the length b of the bolt hole, the spacing c of the bearing seat, the thickness d of the web, and the angle β of the weight-reducing hole as design parameters;

[0054] S52. Taking the maximum displacement value of the model as a constraint condition, the stiffness of the hub meets the requirements and the design parameters corresponding to the minimum volume of the hub are determined.

[0055] In one embodiment, the parameter optimization in step S5 further includes:

[0056] S53. The multi-island genetic algorithm is used to locate the area where the maximum displacement value is located in the design parameter space, and then the nonlinear sequence quadratic programming method is used to accurately optimize the area, and finally the parameter optimization result is obtained.

[0057] Specifically, the design parameters of the hub thickness a, the bolt hole length b, the bearing seat spacing c, and the web thickness d are accurate to 0.01 mm.

[0058] Specifically, the maximum displacement value of the wheel hub is used as a constraint condition for parameter optimization, and the maximum displacement value of the wheel hub is 0.5-1.0 mm.

[0059] In one embodiment, the wheel hub is made of 2014-T6 aluminum alloy.

[0060] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. A design method for a hub for testing aircraft tires, wherein the aircraft tire is mounted on the outer periphery of the hub, the hub is a split hub and is assembled by bolts, and the hub is connected to a tooling shaft of a test bench by a bearing, characterized in that: include: Adapting the wheel hub according to the specifications of the aircraft tire, and establishing a finite element model of the wheel hub; Configuring the material of the wheel hub, the inflation pressure of the aircraft tire, and the radial load and lateral load parameters of the wheel hub on the finite element model; Calculating the finite element model according to the parameters to obtain the maximum stress value and displacement value of the finite element model under radial load and lateral load, and judging whether there is sufficient optimization space for the structure; A finite element model of an axisymmetric plane unit is established for the cross section of the hub, topological optimization is performed on the finite element model of the cross section of the hub under radial load to obtain a calculation result with symmetry, and a primary optimized parameterized geometric model is designed based on the topological optimization result; Based on the parametric geometric model of the initial optimization, five key parameters including the rim thickness are selected, and a combined global optimization and local optimization algorithm is used to perform parameter optimization with the maximum displacement value under lateral load as a constraint condition to obtain the final optimized model of the hub.

2. The design method of the hub for aircraft tire testing according to claim 1, characterized in that: The parameters configured by the finite element model also include the preload force parameters applied by the bolts and the friction coefficient of the contact surfaces of the two wheel hubs.

3. The design method of the hub for aircraft tire testing according to claim 1, characterized in that: The topology optimization includes: An axisymmetric plane model is established for the axial section of the finite element model, and a second-order triangular unit with a size of 2 mm is used for meshing to form a mesh unit; The SIMP topology optimization algorithm is used to retain the mesh elements that affect the stress of the hub structure, and the optimization target is defined as a 40% volume reduction. The topology optimization calculation result is used as the first plane model.

4. The design method of the hub for aircraft tire testing according to claim 3, characterized in that: The parameterized geometric model designed based on the topology optimization result and optimized for the first time includes: The jagged edges of the first plane model are smoothed, and according to the actual installation scenario and processing difficulty of the wheel hub, grid units at the bolt tightening positions are added to obtain a second plane model; A three-dimensional model is generated based on the rotation of the second plane model, and a primary optimization model is obtained after bolt mounting holes are added.

5. The design method of the hub for aircraft tire testing according to claim 4, characterized in that: The parameter optimization includes: Setting weight-reducing holes at the web positions of the primary optimization model, and obtaining the thickness of the hub, the length of the bolt holes, the spacing of the bearing seats, the thickness of the web and the angle of the weight-reducing holes as design parameters; The maximum displacement value of the model is used as a constraint condition to ensure that the stiffness of the hub meets the requirements and the design parameters corresponding to the minimum volume of the hub are met.

6. The design method of the hub for aircraft tire testing according to claim 5, characterized in that: The parameter optimization also includes: The multi-island genetic algorithm is used to locate the area where the maximum displacement value is located in the design parameter space, and then the nonlinear sequence quadratic programming method is used to accurately optimize the area, and finally the parameter optimization result is obtained.

7. The design method of the hub for aircraft tire testing according to claim 5, characterized in that: The design parameters of the hub thickness, bolt hole length, bearing seat spacing and web thickness are accurate to 0.01 mm.

8. The design method of a hub for aircraft tire testing according to claim 1, characterized in that: The maximum displacement value of the wheel hub is used as a constraint condition for parameter optimization, and the maximum displacement value of the wheel hub is 0.5-1.0 mm.

9. The design method for an aircraft tire test hub according to any one of claims 1 to 8, characterized in that: The wheel hub is made of 2014-T6 aluminum alloy.

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