高速列车隧道内初始压缩波传播特性及出口微气压波影响因素研究

Research on the Initial Compression Wave Propagation Characteristics of High-Speed Trains in Tunnels and the Influencing Factors of Micro-Pressure Waves at the Exit

摘要: 本文采用一维可压缩非定常不等熵流动模型改进的广义黎曼变量特征线法，系统研究不同速度，不同列车头型以及不同缓冲结构下形成的初始压缩波在不同长度隧道内的传播演化特性，并根据基于线性声学理论建立的辐射空间立体角模型分析初始压缩波在不同隧道距离传播后向外辐射的微气压波特征以及不同隧道出口地貌对隧道外微气压波的影响规律，参考国内现行的微气压波评价标准，对不同影响因素下辐射的微气压波强度进行评估，判断是否满足国内现行标准。研究表明，初始压缩波压力幅值越大，传播过程中的衰减效应越明显，压力梯度越大，激化效应越明显，隧道长度为激化临界位置时向外辐射的微气压波强度最大，隧道洞口地形越狭窄，辐射的微气压波强度越大。研究结果可为不同线路条件下高速列车通过隧道产生的微气压波评估提供参考。

Abstract: This paper adopts the generalized Riemann variable characteristic line method improved by the one-dimensional compressible unsteady non-isentropic flow model to systematically investigate the propagation and evolution characteristics of the initial compression waves formed under different speeds, different train head shapes, and different buffer structures in tunnels of different lengths. Based on the radiation solid angle model established on the basis of linear acoustics theory, the paper analyzes the characteristics of the micro-pressure waves radiated outward by the initial compression waves after propagation in different tunnel distances and the influence laws of different tunnel exit landforms on the micro-pressure waves radiated outward. Referring to the current domestic micro-pressure wave evaluation standards, the paper assesses the intensity of the radiated micro-pressure waves under different influencing factors and determines whether they meet the current domestic standards. The research shows that the larger the pressure amplitude of the initial compression wave, the more obvious the attenuation effect during propagation, the larger the pressure gradient, the more obvious the excitation effect. When the tunnel length reaches the excitation critical position, the intensity of the micro-pressure waves radiated outward is the maximum. The narrower the tunnel entrance terrain, the greater the intensity of the radiated micro-pressure waves. The research results can provide a reference for the evaluation of micro-pressure waves generated by high-speed trains passing through tunnels under different line conditions.