螺旋线参数对斜拉索气动性能影响的试验研究

Test for aerodynamic performance of inclined cables with different spiral parameters

给斜拉索缠绕螺旋线抑制风雨振的方式,改变了拉索的表面形态,必然会影响拉索的气动性能。在前人对风雨振机理研究的基础上,设计制作三维拉索节段模型,在长安大学风洞中利用皮托管、电子压力扫描阀、数据转换采集系统及自编程序进行了二维流场下螺旋线参数对斜拉索气动性能的影响研究。结果表明:在拉索节段模型自由端2cm处放置端板可以很好的模拟二维流场;斜拉索表面的平均风压分布形态不随螺旋线参数的变化而变化,风压停驻点、上下气流分离点位置不受螺旋线参数的影响,螺旋线附近测点的风压有不规则突变;风阻系数随螺高减小、螺距增大而减小。

The aerodynamic performance of cables with helix is different from that of smooth cables. Based on the former study on rain-wind-induced vibration of cables, the aerodynamic performance of inclined cables with different helix parameters in a wind tunnel of Chang＇an University was investigated using pilot tube, electronic pressure scanning valve, and data conversion and collection systems. It was concluded that （ 1 ） putting a plate 2cm away from the free end of models can simulate 2D flow field well; （2） while wind pressure near the spiral varies irregularly, wind pressure distribution patterns, pressure stops, upper and lower flow separation point positions of the cable surface do not change with the variation of helix parameters ; （3） wind drag coefficient decreases with increases in helix distance and decrease in the height of helix.