高速铁路840 m全封闭声屏障气压荷载数值模拟研究

采用我国干线铁路开行的复兴号动车组,基于计算流体力学软件Fluent,对高速列车以350 km·h^-1速度通过840 m全封闭声屏障及1/2跨和1/4跨会车工况下声屏障的气压荷载分布规律进行数值模拟。结果表明:会车工况下的压力极值均大于单车工况下,且变化规律更为复杂,声屏障中间位置即1/2跨会车时的压力极值达到最大值,最大正压和负压分别为2 672和4 619 Pa,分别为单车工况下的2.05倍和1.87倍;同一截面各测点的气压荷载波动规律相似,但压力极值存在明显差异;单车工况下,声屏障同一截面上不同测点处的极值压差达到0.6 kPa,体现了压力波传递的三维效应。通过数值模拟获得的全封闭声屏障压力极值和气压荷载分布规律,为声屏障结构设计提供理论依据。

Numerical Simulation of Air Pressure Load on 840 m Fully-Enclosed Sound Barrier of High-Speed Railway

Based on the computational fluid dynamics software Fluent, the numerical simulation of the highspeed train passing through the 840 m fully-enclosed sound barrier at the speed of 350 km·h^-1 and trains passing each other at 1/2 span and 1/4 span of fully-enclosed sound barrier is carried out by using the Fuxing EMU,which is operated on the trunk railway in China, to study the distribution of the air pressure load of sound barrier under different working conditions. Results show that the extreme values of pressure under the condition of trains passing each other are greater than those under the condition of single train passing, and the variation law is more complicated. The extreme value of pressure in the middle section of the sound barrier, i. e. trains passing each other at 1/2 span, reaches the maximum. The maximum positive pressure and negative pressure are 2 672 and 4 619 Pa respectively, which are 2. 05 times and 1. 87 times of single train passing. The fluctuating law of the air pressure load at each measuring point of the same section is similar, but the extreme air pressure is obviously different. Under the condition of single train passing, the extreme pressure difference at different measuring points on the same section of the sound barrier reaches 0. 6 kPa, which reflects the threedimensional effect of pressure wave transmission. The extreme value of pressure and the air pressure load distribution law of fully-enclosed sound barrier obtained by numerical simulation can provide theoretical basis for the structural design of sound barrier.