轨道交通百叶窗型风屏障防风效果研究

摘要

为提高列车在复杂风环境中行车的安全性,提出了一种新型百叶窗型风屏障.并以重庆某轨道专用桥为工程背景进行了风洞试验,探究了横风作用下新型风屏障不同叶片旋转角度、不同风屏障布置形式对车桥系统气动特性的影响,对比分析了百叶窗型与普通格栅式风屏障的挡风效果,同时运用CFD对新型风屏障的防风机理进行了进一步阐述.研究结果表明:百叶窗型风屏障可较大幅度降低车、桥系统的力矩系数,相对同等透风率下的普通格栅式风屏障其防风效果更好;百叶窗型风屏障叶片的旋转角度对车桥系统三分力系数均有一定影响,从行车安全性考虑,建议旋转角度控制在90°内最合适;风屏障的布置形式对车桥系统气动特性影响较小,沿桥梁主导风一侧布置即可取得较好的防风效果.%In order to adapt to the complicated wind field environment and improve the safety of vehicle running,a new type of louver wind barrier was developed.Based on a national standard metro bridge as the research object,the louver-type wind barrier was employed to wind tunnel test at the National Engineering Laboratory for High Speed Railway Construction located in Central South University.The effects of aerodynamic characteristics for vehicle-bridge system were studied when the louvertype wind barriers were installed on the bridge in different vane rotation angles,and different arrangement conditions.The windshield performance was also discussed between louver-type and ordinary grid-type wind barriers.Computational Fluid Dynamics(CFD) technology was also applied to explain mechanism of the wind barrier.The results show that the louver-type wind barriers can significantly reduce the moment coefficient of train-bridge system.Moreover,windshield performance of louver-type is more evident in comparison with ordinary grille-type wind barrier.Three-component coefficients of train-bridge system are certain influenced by vane rotation angles.It is suggest that rotation angles should control within 90°considering the running of vehicles.The effects of arrangement condition is limited,so it can make better effect along installment the wind barriers on the bridge of dominant wind direction.