Modeling And Simulation Of Coulping Vibration Between High-Speed Maglev Vehicle And Switch Beam

The switch or turnout is an important component for the ground track transportation. Its structure and conditions have direct effects on the safety, stability and the comfort of trains. In fact, the switch of Shanghai Maglev Line once appeared excessive vibration, which seriously affected the normal operation of the maglev train. Therefore, it is urgent to develop the basic theory and applied technology to slove the dynamic problems of maglev swtich. This paper analyzes vibration modes and natural frequencies of the maglev switch of the Shanghai Maglev Line. Then coupling dynamic model of the maglev train and switch is built to simulate dynamic responses of maglev train-switch system. The pupose of this paper is to provide basic theory and methods for the switch's design and application.Firstly, the maglev switch structure is analyzed, and two kinds of finite element model (FEM) are established using the ANSYS software, the one uses beam element and the other uses plate element. Then, vibration modes and natural frequencies of the maglev switch are analyzed based on the both models. A dynamic model of the TR08 high-speed maglev train is set up after a detailed structure analysis. Using the ANSYS software and SIMPACK software, a FEM of the levitation chassis of maglev vehicle is established, and the model analysis is carried out. Furthermore, the elastic dynamic model and equivalent rigid model of the suspension chassis are built for the whole vehicle dyniamic model.Secondly, this paper builds the coupling dynamic model of maglev vehicle and switch by technological approaches, and realizes the dynamic simulation of the maglev vehicle-switch coupling system. This research shows that although the combined use of the ANSYS software and SIMPACK software can obtaion dynamic responses of maglev vehicle and switch, the computational efficiency is much lower. Moreover, the SIMPACK software limits the number of degrees of freedom of the ANSYS's FEM. So special simulation program for high-speed maglev vehicle dynamic is developed using the FORTRAN language, which combines the ANSYS software to simulate the coupling responses of the naglev vehicle and switch. In this way, the computational efficiency is much faster than the former, and it have no limit of number of degrees of freedom. Obviously, the latter is a better way for the scientific research of maglev vehicle-switch system dynamic.Finally, using dynamic models and numerical simulation techniques developed in this paper, coupling vibration responses of maglev vehicle-switch system in various running conditions are analyzed, which including dynamic responses of the maglev vehicle-switch system when the switch is in bent off position. Numerical results show that the vertical and lateral vibrations at the middle of the third span are lager than the others. When the maglev vehicle passes through the bent-off switch, the lateral displacement of switch beam is larger than its vertical displacement. For the plate element model of the switch, the acceleration and displacement responses of the flange are larger than that of the bottom of the main beam. It shows that the flange have violent local vibrations especially when the maglev vehicle passes through the swtich with a low speed.