斜拉索上水线气动性能的大涡模拟研究

发布时间：2018-03-31 00:07

本文选题：斜拉桥拉索　切入点：风雨激振　出处：《土木工程学报》2014年10期

【摘要】：上水线在斜拉索上表面的形成是拉索发生风雨激振的关键因素,目前上水线的形成机理尚不清楚,现有风洞试验方法难以研究作用在上水线上的风致表面摩擦力。采用大涡模拟方法,针对带上水线拉索模型,研究水线处在不同位置时,作用在拉索和上水线上的平均气动力特性,得到作用在上水线上的风致压力和风致表面摩擦力随水线位置的变化规律。研究表明:上水线受到的摩擦气动力与压力气动力为同一量级,在研究水线形成机理时不可忽略;在一定的来流风速范围内,摩擦气动力和压力气动力的合力可使上水线稳定在使拉索气动力发生剧烈变化的位置;在过小的风速下,水线不会稳定在拉索表面;而过大的风速会使水线远离使拉索气动力发生剧变位置。首次得到上水线摩擦气动力系数随水线位置角变化的曲线,有助于建立更准确的水线运动微分方程和更精细的拉索风雨激振理论分析模型。
[Abstract]:The formation of water line on the upper surface of stay cable is the key factor of wind and rain induced vibration of cable. At present, the formation mechanism of upper water line is not clear, and the existing wind tunnel test method is difficult to study the wind induced surface friction acting on the line.Using the large eddy simulation method, the average aerodynamic characteristics of the waterline acting on the cable and the upper water line when the waterline is in different positions are studied in the light of the cable model along the belt.The variation of wind-induced pressure and wind-induced surface friction along the waterline is obtained.The results show that the friction aerodynamic force and the pressure aerodynamic force are of the same order of magnitude, so the formation mechanism of the waterline can not be ignored.The combined force of friction aerodynamic force and pressure aerodynamic force can make the upper waterline stable in the position where the aerodynamic force of the cable changes dramatically, and at too small wind speed, the waterline will not stabilize on the surface of the cable.Too high wind speed will make the waterline away from the cable aerodynamic force change position.For the first time, the curves of the friction aerodynamic coefficient of the upper waterline with the position angle of the waterline are obtained, which is helpful to establish a more accurate differential equation of waterline motion and a more precise theoretical analysis model of the wind and rain excitation of cables.
【作者单位】：上海大学;同济大学土木工程防灾国家重点实验室;
【基金】：高等学校博士学科点专项基金资助(20113108120024) 上海市教育委员会科研创新项目(14YZ004)
【分类号】：U448.27;U441.3

【参考文献】