Study On Optimization For The High Speed Maglev Car Body Structure With Sandwich Panels

As a new rail transportation mode , high speed maglev is attracting more attention recently. Its technology is getting mature after many years' research and testing. It will exert large advantage and potency in high speed rail transport area in the new century. The success of Shanghai maglev line indicates the beginning of commercialization for high speed maglev. At present, shanghai maglev train is made in Germany. In order to promote the development of high maglev transport in china, realizing national production of maglev train has great significance. The high light weight technology is one of the key technologies of maglev car body design due to the limited magnetic suspension force. This thesis emphasizes on structural analysis and light weight optimization research for new maglev car body structure base on the existing maglev train design technology.Shanghai maglev train uses multi-method to realize light weight design, one of the methods is the application of new structure material named sandwich panel in car body. This material is less used in our country, and it hasn't been used in domestic rail vehicle. So we have less knowledge about this material, and the analysis method for large-scale structure with this material needs to be studied. This thesis firstly analyses and compares several modeling methods for sandwich pane structure, discusses the proper FEA modeling method which is with both high accuracy and economy for large-scale sandwich panel structure. Then an analysis of high speed maglev car body is performed using FEA software MSC.NASTRAN to know about its structure strength, stiffness and dynamic behavior. Based on this, the optimization model of high speed maglev car is established according to structure optimization theory, in which the weight is defined as objective function, the panel thickness is regarded as design variable, and stress, deflection and frequency are considered as constraints. A satisfied design layout of structure for high speed maglev train is obtained after the optimization. At last, this thesis studies on the optimization approach of sandwich panel in which the thickness of skin panel is defined as design variable, and explores optimization technology for light weight design of car body structure with sandwich panels. The suggestion and expectation is put forward as well.