排障器区域对机车气动性能影响研究

Research on Influence of Cowcatcher Area on Aerodynamic Performance of Locomotive

机车运行过程中,排障器能有效地清除轨道上的障碍物,同时由于受到气动阻力作用,排障器对机车的气动性能有一定影响。采用求解三维、不可压、定常N-S方程的数值计算方法分别对安装不同外形排障器的机车运行时气动性能进行模拟,并针对模拟结果提出外形结构优化方案。结果表明:在机车运行时,不同外形排障器迎风面受到的气动阻力均较大,占机车气动总阻力的26.09%~31.82%;通过对排障器的迎风端面进行开孔处理,可以有效地减少排障器受到的气动阻力,阻力系数减少2%~10%;在同等的开孔面积下,开孔方向对减阻效果有一定影响,横向开孔方案比竖向开孔方案减阻效果更佳。

During the running process of the locomotive,the cowcatcher can effectively remove obstacles on the track.At the same time,due to the action of aerodynamic resistance,the cowcatcher has a certain impact on the aerodynamic performance of the locomotive.Based on the numerical calculation method using the three-dimensional unsteady compressible Reynolds-averaged N-S equation,the aerodynamic performance of the locomotive with different shapes of cowcatcher was simulated and the optimal scheme of shape structure was proposed according to the simulation results.The computational results show as follows:The aerodynamic resistance on the windward end of the cowcatchers with different shapes is large,accounting for 26.09%to 31.82%of the total resistance of the locomotive.The aerodynamic resistance can be effectively reduced by punching the cowcatcher,resulting in the reduction of the drag coefficient by 2%to 10%.Under the same opening area,the direction of the opening hole has a certain effect on drag reduction,with the transverse opening scheme being more effective than the vertical one.