【作者】 张雷；

【导师】 田红旗；

【作者基本信息】 中南大学 ， 载运工具运用工程， 2010， 硕士

【摘要】 高铁线路中新型隧道洞门使用广泛,在当前动车组车速较高的情况下,如何利用隧道洞门结构较好的缓解隧道空气动力效应已成为高速铁路隧道设计和既有线隧道为适应列车提速必须考虑并解决的关键问题。本文通过求解三维、可压缩、非定常N-S方程,采用滑移网格技术真实模拟隧道内空气的复杂流动,并结合动模型试验,对高铁线路中新型隧道洞门形式下的隧道空气动力效应进行了系统研究,得到了以下重要结论：隧道入口洞门护坡结构的面积及其斜切斜率基本不影响隧道空气动力效应,隧道出口洞门护坡面积增至9倍隧道净空面积过程中,微气压波幅值明显增大,之后其不随着护坡面积的增大而改变,当出口护坡由竖直变化至斜率1：1.125时,微气压波幅值随着斜切斜率的减小线性降低,之后其基本不随斜率变化而变化。在隧道的入口端,相比传统的端墙式隧道洞门,新型隧道洞门对车体表面、隧道壁面最大压力幅值基本无影响,但其可缓解初始压缩波的压力梯度和隧道出口微气压波,其中帽檐斜切式隧道洞门的缓解效果最好,另外隧道出口微气压波随隧道洞门斜切斜率的减小近似成线性关系降低。明确了断面扩大无开孔缓冲结构最佳长度和断面扩大率,得出帽檐斜切式隧道洞门与缓冲结构组合后,隧道出口微气压波相比仅有缓冲结构时的变化规律,在本文研究的开孔式组合洞门中,确定了对隧道气动效应缓解效果最好时的洞门开口率及开孔方式。更多还原

【Abstract】 The tunnel portal is widely used on New high-speed rail way line, in the current time, the speed of EMU is higher than every time before, and how to use the tunnel portal to alleviate aerodynamic effects of tunnel better has become the key issues that must to be considered and address -ed in high-speed railway tunnel design community,and for the existing line tunnels to adjust to the promoting of the train Speed.In order to simulate the complex airflow inner tunnel truly, the Navier-Stokes equations with three dimensional, compressible and unsteady viscous fluid were taken as the control equations, and the technology named slippage grid was adopted. Then, the aerodynamic effects of the tunnel under different tunnel portals were studied systemicly combining with the model experiment, and some important conclusions were gained as following:The area and oblique slope of the slope protection around portal on the tunnnel entrence has little influence on the aerodynamic effects of the tunnel; The micro-pressure amplitude significantly increased until the area of slop protection on the the tunnel exit comes to 9 times of the tunnel area, then it does not change as the increase of the area, and the micro pressure wave amplitude decreases linearly with the decrease of slope protection oblique slope,when the slope of the tunnel exit slope protection changes from vertical to slope of 1:1.125, then micro pressure wave amplitude does not change with changes of the slope.Compared to the traditional wall tunnel portal on the tunnel entrance, the new kinds of tunnel portals almost has no influence on the maximum pressure amplitude of the train and tunnel surfaces, but they can ease pressure gradient of the initial compression wave and micro-pressure waves on the tunnel exit, and the mitigation effects of hat peak oblique tunnel portal are the best, in addtion, micro pressure wave amplitude decreases linearly with the decrease of oblique slope of the obliqued tunnel portal.The best length and enlarged transect ratio of enlarged transect windowless hoods were made clear; and compared to buffer structure, micro pressure wave changes were acquired when the portal is the combination of hat peak oblique and buffer structure; then the best vent ratio and opening form among windowed combination portal studyed in this paper更多还原