瞬态摩擦对高速铁路隧道初始压缩波传播的影响

摘要

Compression wave is generated when a high -speed train enters the tunnel portal.There may be envi-ronment problem when the micro -pressure wave radiated subsequently at the exit portal.The friction of the tunnel wall is the primary factor which affects the propagation of the initial compression waves.The change rate of pres-sure of the compression waves and the strength of the compression wave arrived at the exit portal are affected actu-ally.With the one -dimensional compressible unsteady non -homentropic flow model,the characteristics of the propagation of the initial compression wave caused by a CRH380A entering a tunnel was studied rapidly through a 1D code,in which the transient friction was considered.And its effects at different locations were shown.The effect of transient friction on pressure change and its ratio at various blockage ratio and operation speed were stud-ied.The effect of the transient friction in simulating the propagation of initial compression waves was studied qualita-tively and quantitatively.It is helpful for the future usage of the transient friction in the one -dimensional flow model.%高速列车车头驶入隧道产生初始压缩波，其传播到隧道出口向外辐射引起微压波现象，危害周围环境。而隧道壁面摩擦是影响初始压缩波洞内传播的重要因素，从而影响微压波的强度。采用考虑瞬态摩擦的一维可压缩非定常不等熵流动模型研究初始压缩波洞内的传播过程。研究瞬态摩擦对 CRH380A 驶入隧道引起的初始压缩波传播的影响，给出了不同传播距离处瞬态摩擦的影响特性，获得了不同阻塞比及不同速度等级下瞬态摩擦对压缩波压力变化和压力梯度的影响特性。得出的研究结果可为今后正确考虑一维流动模型中的瞬态摩擦项提供依据。