EMU Underframe Optimization Based On Mesh Deformation

The rapid development of China’s high-speed railway has higher demands on the performance of the EMU itself, and the best use of the material is the main idea of structural optimization design.It’s well-known that the lightweight body is multi-disciplinary, multi-parameter and multi-constrained optimization problems of complex systems. In this paper, we analyzes the structural strength and modality of Chinese standard EMU TC01 body structure, on this basis, it has been put forward recommendations for the design and optimization of undercarriage and under beam. In this paper, the concrete work is as follows:(1) Simplified the three-dimensional model of China standard railway car before we built the finite element model by HyperMesh12.0.(2) According to EN 12663:2000 standards, the vehicle body structure was a combination of 10 kinds of major conditions of the calculation, carried out on the body strength, stiffness and modal analysis.(3) We use Isight optimization platform and Simcode for mesh deformation. Some of the parameters, such as the thickness of underframes, high-low cover of the side beams and the stiffened plates and the angle of the chassis stiffened plate, was optimized with Sculptor and ANSYS, a finite element analysis software, after getting the results of the analysis of vehicle body. The optimization was taken under multi-working conditions, taking the thickness of the plate and the angle of the reinforcement plate as independent variables, taking the weight of the vehicle body as the objective function, and taking the rigidity, strength and modal of the vehicle body as the constraint conditions. First of all, we got sample extractions about designed variables and responses, and detected the sensitivity of the responses. Then built the approximate model with the differences of plate thickness was considered. Analyzed with 6σ method ensured the plate can satisfy the index of the vehicle body although the plate thickness is fluctuating. Optimizing with PSO has an ideal effect and high efficiency. The strength, stiffness and modal of the vehicle body are not obviously decreased while the weight is obviously reduced after being optimized.(4) According to the optimization results, check on the body condition, and according to changes in the angle of the ribs Brace, design optimized Brace.(5) Taking into consideration of the plate thickness deviation in the process of machining, this article provide the certain basis for the next step in the EMU design improvements, especially the thickness of the plate and stiffened plate layout problems; provide some ideas for High-speed train body structure analysis and optimal design of large structures; make a certain amount of research for the next step to enhance the performance of EMU body.