Research On Topology Optimization Method Of Multi-Materials-Assembly Structure

Topology optimization of multi-materials-assembly structure is a research hotspots in the field of structural optimization design.Which aims at finding the optimal layout of multiple materials in design space under given design space,optimization objectives,constraints,load conditions,boundary conditions and physical parameters of various materials that constitute the structure by optimization design method.A structural topology design scheme with material saving,light quality and excellent performance can be obtained based on this method in the stage of product conceptual design.This lightweight design method has an important theoretical research significance and engineering practical value for the complex product structure design represented by automobile.Compared with the topology optimization of single-material structure,the topology optimization of multi-materials-assembly structure is much more complex in the mathematical description of the topology optimization model,optimization strategy and numerical computation scale.Under this background,a topology optimization method of multi-materials-assembly structure based on Nash game theory was proposed in this thesis.The main contents are as follows:(1)A topology optimization method of multi-materials-assembly structure based on Nash game theory was proposed.And the mathematical model,material interpolation method,structural analysis method,design variable sensitivity analysis method,optimization solution strategy and numerical instability treatment method of topology optimization of multi-materials-assembly structure were studied.(2)The topology optimization method of multi-materials-assembly structure based on Nash game theory was verified by several classical examples in topology optimization research field,such as structural stiffness design,compliant mechanism design and heat conduction structure design,and so on.(3)On the basis of the project of the cooperation between the school and the enterprise,the topology optimization method of multi-materials-assembly structure based on the Nash game theory was applied in the design of a special function vehicle frame.A lighter weight frame structure(compared with the target vehicle,the weight of the frame is reduced by 17.1%)was obtained under the condition of improving the performance of the frame,and a good engineering application effect was achieved.(4)In order to overcome the problem of inefficiency caused by the number of elements,design variables and load conditions in practical engineering applications,a parallel computing method accelerated by GPU was adopted to accelerate the numerical solution process and a good application results was obtained.It also provided a feasible direction for the application of topology optimization method of multimaterials-assembly in practical engineering.On the premise of engineering application,a topology optimization method of multi-materials-assembly structure was proposed in this thesis.And the feasibility of this method was verified by topology optimization design of a multi-material-assembly frame.Which lays the foundation for applying topology optimization method of multimaterial-assembly structure in practical engineering problems.