单列高速列车通过隧道空气阻力数值模拟研究

Numerical Simulation on Air Resistance of High-speed Train Passing through Tunnel

应用一维可压缩非定常不等熵流动模型和广义黎曼变量特征线法,研究中国标准动车组CR400AF单列车通过隧道时的空气阻力。详细分析高速列车通过隧道时空气阻力与列车周围空气压力、空气流速及压缩波和膨胀波传播叠加三者间的关系,揭示高速列车通过隧道时空气阻力的变化特征。研究隧道长度、阻塞比、车速及列车长度对高速列车通过隧道(尤其长大隧道)时空气阻力的影响规律。结果表明,研究高速列车隧道压力波时,只需要考虑列车驶入驶出隧道诱发的压缩波和膨胀波的反射和叠加;而在研究列车空气阻力和列车周围空气流速时还必须同时考虑压缩波和膨胀波的传播方向。单列车通过隧道的空气阻力均随隧道长度、阻塞比、车速和列车长度增大而增大。特长隧道时,各因素按其影响程度由大到小排列依次为车速、列车长度、阻塞比和隧道长度。其中,平均空气阻力与车速的2次方、与阻塞比的0.60~0.79次方、与隧道长度的0.02次方近似成正比。

Using one-dimensional(1D)compressible unsteady non-homentropic flow model and the method of characteristics of generalized Riemann variables,air resistance of a CR400AF passing through a tunnel is studied.The relationship among air resistance,pressure changes and air velocity around the train,and the reflection and intersection of the compression wave and expansion wave is analyzed in detail.And the characteristics of air resistance is revealed.The effects of tunnel length,blockage ratio,train velocity and train length on air resistance of the train passing through a tunnel(especially long tunnel)were studied.Results show that only the reflection and intersection of the compression wave and expansion wave induced by the train entering or exiting the tunnel is needed in studying the pressure wave.However,the propagation directions of compression wave and expansion wave must be considered simultaneously when studying the air resistance and air velocity around the train.The air resistance increases with tunnel length,blockage ratio,train velocity and train length.According to the degree of influence on air resistance in long tunnel case,train velocity,train length,blocking ratio and tunnel length is for the descending order.The average air resistance is approximately proportional to 2 power of train velocity,0.67-0.79 power of blocking ratio,and 0.02 power of tunnel length.