高速列车出隧道空气动力效应数值模拟研究

发布时间：2018-05-04 05:22

本文选题：高速列车 + 隧道　；参考：《兰州交通大学》2016年硕士论文

【摘要】：高速列车以其不可替代的优势在世界交通运输业中占有重要位置。随着列车运行速度的不断提高,高速列车隧道空气动力学问题日益显著。列车高速驶出隧道过程中,洞内外空气流动空间逐渐改变,产生隧道压力波、出口波等现象,高速列车的气动性能也随之发生改变。这将影响列车的安全运行及旅客的舒适性,大风环境下该影响作用尤为突出。因此,研究高速列车驶出隧道过程中的空气动力效应问题具有十分重要的意义。本文通过数值计算方法,以简化的CRH5型动车组和兰新第二双线的红西隧道出口端及其附近局部地貌为研究对象,对不同条件下列车驶出隧道过程的压力场、速度场及气动载荷进行数值计算分析,得到列车-隧道系统的空气动力特性变化规律。首先,对列车从不同形式的隧道洞口驶出时车头压缩波、车尾膨胀波和隧道出口波的形成机理进行了研究。对列车从直切式隧道洞口驶出时不同时刻的压力场和列车从斜切式隧道洞口驶出时不同时刻的压力场和速度场的变化进行了分析,说明了车头压缩波、车尾膨胀波和隧道出口波的形成机理。其次,对比分析了不同位置或不同形式洞口下的上述三种压力波的波动特性。以帽檐切削式洞口为基础,对比分析了隧道端口附近不同位置的车头压缩波、车尾膨胀波和隧道出口波的压力变化以及列车从不同形式的隧道洞口驶出时的压力变化规律。再次,对列车驶出隧道前后列车表面与周围环境的压力变化特性进行了研究。对不同条件下列车运行的压力和速度变化进行了分门别类的分析,并阐述了其变化原理,得到了列车通过相应位置时的压力变化规律;对不同过渡段的压力极值变化进行了分析,初步得到了不同过渡段对列车运行的影响作用。最后,对列车运行过程中气动载荷的变化特性进行了研究。通过极值比较,对不同条件下列车驶出隧道过程中各节车的气动载荷变化特性进行了分析,说明了不同条件对列车各节车气动参数的影响作用。以上研究结果可作为高速列车空气动力学深入研究的基础,同时可为解释高速列车驶出隧道的空气动力效应提供有益的参考。
[Abstract]:Because of its irreplaceable advantage, high-speed train plays an important role in the world transportation industry. With the increasing of train speed, the aerodynamic problem of high-speed train tunnel is becoming more and more obvious. The air flow space inside and outside the tunnel changes gradually in the course of high speed train coming out of the tunnel, resulting in tunnel pressure wave, exit wave and so on. The aerodynamic performance of high-speed train also changes with it. This will affect the safe operation of the train and the comfort of passengers, especially in the windy environment. Therefore, it is of great significance to study the aerodynamic effect of high-speed train in the process of exiting the tunnel. In this paper, the simplified CRH5 EMU and the local geomorphology near the exit of the Hongxi Tunnel on the second double track of Lanxin are taken as the research objects, and the pressure field of the train coming out of the tunnel under different conditions is studied. The aerodynamic characteristics of train tunnel system are obtained by numerical analysis of velocity field and aerodynamic load. Firstly, the formation mechanism of front compression wave, tail expansion wave and tunnel exit wave is studied. The variation of pressure field and velocity field at different times when the train is coming out of the orifice of a direct-cut tunnel and the pressure field and velocity field at different times when the train leaves the tunnel entrance of a oblique tunnel is analyzed, and the compression wave at the front of the train is explained. Formation mechanism of tail expansion wave and tunnel outlet wave. Secondly, the wave characteristics of the above three kinds of pressure waves under different positions or different forms of openings are compared and analyzed. Based on the brim cutting hole, the pressure changes of the front compression wave, the tail expansion wave and the tunnel outlet wave in different positions near the tunnel port are compared and analyzed, as well as the pressure variation law of the train coming out from different tunnel openings. Thirdly, the pressure variation characteristics of the train surface and surrounding environment before and after the train leaving the tunnel are studied. In this paper, the variation of train pressure and speed under different conditions is analyzed, and the principle of the change is expounded, and the law of pressure variation when the train passes through the corresponding position is obtained. The variation of pressure extremum in different transition sections is analyzed, and the influence of different transition sections on train operation is preliminarily obtained. Finally, the variation characteristics of aerodynamic load during train operation are studied. Through the comparison of extreme values, the variation characteristics of aerodynamic load of each section of train in the process of train exiting the tunnel under different conditions are analyzed, and the effect of different conditions on the aerodynamic parameters of each section of the train is explained. The above results can be used as the basis for the further study of aerodynamics of high-speed trains and provide a useful reference for explaining the aerodynamic effects of high-speed trains coming out of tunnels.
【学位授予单位】：兰州交通大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：U451.3

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