Simulation Of Rail Moving Boundary Based On Lattice Boltzmann Method

With the high development of high-speed railway construction, the vehicle-rail- bridge interaction has become an important issue in the world. The traditional finite element method needs too much computation in dealing with vehicle - rail - bridge coupling vibration problems, due to the rail surface and the complex contact analysis. However, the Lattice Boltzmann method has incomparable advantages in multi-scale analysis and parallel computing compared with traditional finite element method, it can be used to solve the high-speed collision problem between vehicle and rail, and study the interaction mechanism of vehicle-rail; In addition, the Lattice Boltzmann method also has advantages in dealing with moving boundary and curved boundary, it can process a different approach to the interface treatment of beam and rail. Based on the above ideas, this paper includes the following aspects:1,Based on the basic theory of Lattice Boltzmann method, the appropriate basic lattice Boltzmann model is derived for the problem in this paper in detail.2,According to the treatment method of complex boundary and loading external loads in Lattice Boltzmann method, High-speed contact and collision problem of vehicle and rail is simulated by LBM because it has advantages in the treatment of curved boundary, the effect of rail irregularity to the high-speed vehicle also is simulated by LBM because it has advantages in the treatment of moving boundary.3,C++ program is generated based on Lattice Boltzmann numerical method, then the dynamic interaction of the high-speed vehicle and rail is analysised, and the result is compared with the related date obtained by finite element method.The results of this paper prove that LBM is useful on the preliminary simulation of rail moving boundry. Considering the rail irregularity factors, we can know that the jumping phenomenon of the vehicle is more obvious produced by a larger rail irregularity, and the dynamic response caused by the series changing rail irregularity is significantly greater than the half-wave sine function changing rail irregularity. This result is consistent with the conclution obtained by finite element method.