加减速时地铁列车隧道气动性能研究
Study on tunnel aerodynamic of subway train during acceleration

采用三维、可压缩、非定常N-S方程的数值计算方法，研究A型地铁列车在隧道内加减速时车体表面压力变化和车内压力变化，分析隧道净空面积与密封指数的关系，并采用动模型实验验证数值计算准确性。研究结果表明：列车在隧道内运行时，随着阻塞比的减小，测点压力幅值随之减小，主要体现在对正峰值的影响，压力变化规律基本一致；阻塞比越小，列车表面压力幅值随列车长度方向的变化趋势越平缓；列车以匀速、减速和加速3种方式运行，隧道断面为22 m2时，根据美国标准列车气密性需分别大于6，3和6 s，根据国内标准需分别大于10，6和10 s；隧道净空面积小于35 m2时，根据美国标准列车气密性需分别大于2，0.7和1.5 s，根据国内标准需分别大于3，0.4和1.5 s。
Based on unsteady N-S equations of three-dimensional and compressible viscous fluid, the paper research the transient pressure variation on the car surface and the internal pressure on the condition that the A-type subway train accelerate in tunnel, analyzed the relationship between the tunnel clearance area and the seal index. The results show that when the train runs in tunnel, the pressure amplitude of the measuring point decreases with the decrease of the blocking ratio, which is mainly reflected in the influence of the positive peak value, and the pressure variation rule, is basically the same. Along the length of the train, the trend of the pressure amplitude variation is more gentle with the smaller the obstruction ratio. When the train runs in three modes, the air tightness of the train must reach 6 s, 3 s, 6 s according to the American standard, and 10 s, 6 s, 10 s according to national standard, in 22 m2 subway tunnel. When the tunnel clearance area is less than 35 m2, the air tightness of the train should be greater than 2 s, 0.7 s, 1.5 s according to the American standard, and 3 s, 0.4 s, 1.5 s according to national standard