Optimization of aerodynamic effect section of underground railway tunnel in high-speed modes

Adopting three-dimensional numerical simulation method and dynamic mesh technique, analyses the aerodynamic effect when a train passes through different underground railway tunnel sections at high speed, obtains the pressure changes of the train surface, and acquires the inside pressure of the train from the outside pressure. Chooses the optimal section by referring the pressure comfort codes of US underground railway. Analyses the optimal aerodynamic effect section of B-type and A-type trains with different airtight indexes at the train speeds within 100 to 140 km/h, under the conditions of single hole tunnel and ordinary interval tunnel respectively, providing references for the design of high-speed underground railway tunnel.