The Digital Simulation Analysis Of Aerodynamic Effect Produced By High-speed Train Passing A Railway Tunnel

Since 1960's, high-speed railway has grown up in developed country and railway developed into a new age. High-speed railway thrived to internationally lead to a revolution in traffic transportation. However, with the train increasing speed, aerodynamic effects generated by a train passing through a tunnel will generate aerodynamic problems that did not appear at lower speed. At a higher speed, the train entry into a tunnel will cause obvious pressure fluctuation in tunnel and micro-pressure wave radiated from the exit of the tunnel, which will influence passengers' comfort and environment around a tunnel. Therefore, lucubration of tunnel aerodynamic effect's mechanism and corresponding alleviation measure is very necessary.This thesis is based on the project of "The research on the aerodynamic effectin the underground railway station", which is from the second surveyed and design institute of China Railways, and also based on the developing project of "Testing and research on the related technology of the aerodynamic effect in the underwater railway tunnel named 'shizhiyang'", which is from the national railway department. Research on the lucubration of tunnel aerodynamic effect's mechanism and corresponding alleviation measure was carried out at the same time.The beginning, this paper has made some attempt to the calculating grid referring to kinds, characteristic and meshing methods. The train's grid was simplified, and the shaft's grid was optimized. Then, this paper made some attempt to Principle and realization method to Calculating boundary in Fluent. Some important boundary parameter was studied. Moving mesh and dynamic mesh was compared, the better method concerning a train passing a tunnel was given. Two physics models was compared, the better physics model concerning a high-speed train passing a railway tunnel was given. At last, this paper have made some attempt to UDF and acoustics model, these work has made preparation to the job coming.This paper have also made some attempt to these three following areas: three length of train passing through a tunnel has been compared through digital simulation, the result of the train's length to the compressed-pressure wave was given; four length of shaft's opening rate has been compared through digital simulation and model testing, the result of the shaft's opening rate to the compressed-pressure wave in max peak and gradient was analyzed; A disadvantage to the shaft's site was sum up.