Simulation And Analysis On Aluminum Alloy Bodywork Of Metro

Nowadays, aluminum alloy material has been widely used on Metro Vehicle. And as known to all, the reliability, security and other performance of the aluminum alloy car-body for Metro Vehicle directly relate to the safety of passengers, so the performance of aluminum alloy car-body is very important. The paper uses an aluminum body of metro vehicle as the research object, in the design of drawing stage, the method of numerical simulation is used to analyze the performance of the body. Details are as follows:Firstly, based on Three-dimensional geometric model of the Aluminum Alloy Car-body for Metro Vehicle, the finite element model used for static strength analysis is established by using I-DEAS and Hypermesh. Seven load cases are determined according to EN12633-2003 Standards, and the results of those cases are analyzed, at last, the paper evaluates the static strength of the body's main parts.Secondly, in accordance with the basic modal analysis principles, the modal analysis is respectively done to the steel body in the servicing and overloading state. Then, analysis is made to the first bending frequency and the first torsion frequency which is extracted from the results.Then, by using the software Hypermesh, finite element model is established which is used for the crash simulation analysis of large deformation. "Crashworthiness" analysis is made to energy-absorbing structure in front of the body, and the deformation mode design of energy-absorbing structure is completed. And "crashworthiness" analysis of the improved energy-absorbing structure is conducted. According to the design requirements of energy-absorbing structure, we determine the crash conditions as follows:(1) the empty vehicle crash into the fixed plane rigid wall at speed of 50km/h. (2) vehicle in the servicing state crash into the fixed plane rigid wall at speed of 24km/h. Then, analysis is done to the deformation and energy of the energy-absorbing structure and variation law of shock, speed and acceleration with time. Based on this, we can be sure of that the "crashworthiness" of the improved energy-absorbing structure of the body reached the absorbing energy requirements.Lastly, the equivalent structure stress method is used for calculation of stress concentration and prediction of fatigue life at body main weld. According to body structure and welding process diagram, the finite element model is established which is used for analyzing stress concentration and predicting fatigue life. And by the standard of "EN 12663: 2000", the vertical load and transverse load conditions for static strength analysis are determined, and then the nodal force of each load cases are extracted to obtain regularity of distribution of structural stress for evaluating welds. The life of key parts with welds are predicted according to the standard of ASME, and the results show that fatigue life of body's key assessment welds meet the design requirements.