城市快速轨道交通压力波及列车气密性措施分析

Analysis of the Impact of Urban Rapid Transit Pressure on Train Airtightness Measures

针对快速轨道交通列车在隧道内气动压力变化较快造成的舒适度降低问题,对隧道内径尺寸、泄压方案对车内压力的影响进行研究。首先根据相关规范选定压力舒适度标准,建立包含列车模型、隧道模型及隧道口泄压措施的有限元模型,然后分别对不同隧道内径、不同气密指数条件下列车内外压力的变化进行研究,最后对隧道入口设置缓冲方案对车内压力的影响进行分析。研究结果表明:当隧道内径由6.0 m增加为6.1 m时,车内压力变化最大值约降低4.2%,继续增大隧道直径对减小车内外压力变化值作用有限;当气密指数≤6s时,每增加1 s,车内压力变化最大值约减小15%~25%;隧道洞口设置全封闭声屏障作为缓压结构时,车内压力变化最大值可降低约40%~50%;为提高整车气密性,可采取提高司机室/客室车门密封性、在新风口和废排风口设置启动压力保护阀以及提高车身及贯通道密封性等措施。

To address the issue of reduced comfort resulting from rapid aerodynamic pressure changes inside the tunnels used for urban rapid transit trains,a study was conducted on the effects of the tunnel diameter and pressure-relief schemes on in-car pressure.First,pressure comfort standards were selected based on relevant regulations,and a finite element model was established,which included a train model,a tunnel model,and pressure relief measures at the tunnel entrance.Subsequently,the pressure variations inside and outside of a train were investigated for different tunnel diameters and airtightness indices.Finally,the impact of implementing buffering schemes at the tunnel entrance on the in-car pressure was analyzed.The research results indicated that when the tunnel diameter increased from 6.0 m to 6.1 m,the maximum in-car pressure variation decreased by approximately 4.2%,with further increases in tunnel diameter having a limited effect on reducing the pressure variation.When the airtightness index was≤6 s,each additional second resulted in a 15-25%reduction in the maximum in-car pressure variation.Additionally,when a fully enclosed sound barrier was installed at the tunnel entrance as a pressure-relief structure,the maximum in-car pressure variation could be reduced by approximately 40-50%.Measures can be taken to enhance the overall vehicle airtightness,such as improving the seals around the doors for the driver's cab and passenger cars,installing pressure protection valves at fresh-air inlets and exhaust outlets,and enhancing the seals on the vehicle body and intercarriage passageways.