Structural Stiffness Optimal Design For Vehicle Body Of CRH5EMU Based On Sectional Moment Of Inertia

This paper studies the M2S vehicle body of CRH5electrical multiple units, starting with the research on the cross section of the windowless part of the central body. The above-mentioned cross section is the structural basis for manufacturing hollow profile extrusion for vehicle bodies. Oriented at seeking the maximum bending resistance moment of inertia yet without increasing the cross-sectional area, changing the interior and exterior contours, or decreasing the torsion moment of inertia of the cross section, the paper applies the principle of structural optimization and analyzes the parameters’characteristics of the vehicle’s cross section based on structural mechanics.In order to calculate changes in the vehicle’s cross sectional properties when the geometrical parameters of the chassis changes, part of the structural parameters of the chassis are selected as parameters for optimization design. The relation between property parameters of the cross section and stiffness of the vehicle is analyzed to determine the optimization direction. Optimization processes based on Isight platform have been established, and simulation and optimization integration has been conducted on SolidWorks and Ansys to ascertain data and the relation between input and output of files. By making use of Isight software and genetic algorithm, shape optimization has been applied to the parameters geometrical properties of the chassis’s cross section with the bending resistance inertia moment of the vehicle’s cross section as optimized objective function and limitations of cross sectional area, torsion moment of inertia and geometry as constraint functions.Based on the whole vehicle body and EUstandards<BS EN12663:2000railway applications---structural requirements for railway vehicle body>,design the vehicle structure and calculate load calculation, establish finite element model in hypermesh, check the vehicle strength and mode shape.Finally, optimization results are analyzed, and sectional optimal design method is provided.The paper has provided valuable insights to the structural analysis of high-speed train and structural optimization for major projects. Meanwhile, it sets the foundation for an in-depth research on the optimization design of railway vehicles.