Optizimation Design Of Carbody Cross Section For High Speed Trains

The car body design is an important component for the study of high-speed train. In the operation process of high-speed trains, the car body not only transfers the traction and braking force to the coupler, but also bears all sorts of equipment load, longitudinal and transverse impact load. Therefore, the car body must have enough strength and rigidity, satisfy the requirements of relevant technical standards and ensure the safety and steadiness of the operation of trains.In this paper, the finite element model of a high-speed train aluminum alloy car body is established using the Hypermesh software. Its static strength is calculated, the calculation results of the structure strength and stiffness are analyzed, and modal analysis is carried out; Taking the car body chassis as the research object, the topological optimization and size optimization are carried out. The optimum section configuration of car body chassis is discussed, and the optimization results are validated. The main contents are as follows,1. Set up of the finite element modelDue to complexity of the car body structure, it is simplified properly and finite element model of the car body is built in Hypermesh software.2. Static strength and modal analysis of car bodyAccording to the European Committee for Standardization, Railway applications-structural requirements of railway vehicle bodies, the car body strength and mode are analyzed under the four different working conditions. The stress distribution of the car body is summarized. Simultaneously, the stiffness of car body is evaluated according to’Railway Rolling Stock Design and Test to Identify Strength Norms (TB/T1335-1996)’, which provide constraints condition for the optimization of car body chassis.3. Structure optimization of the car body chassisThe car body chassis is optimized using the OptiStruct optimization software. First of all, the topological optimization of car body chassis is carried out based on the conceptual design. The car body chassis with optimum cross-section configuration is got according to the design requirements and optimization goal. On the basis, the more detailed size optimization is carried out, optimal sizes of the cross sections are obtained based on the optimal objective function. After the optimization, the static strength of the car body is analyzed again and the calculation results of static strength analysis before and after the optimization are compared.