梯形平面反对称布置双塔楼的风场干扰研究

Study on wind field interference of trapezoidal plane anti‐symmetric twin towers

针对梯形平面反对称布置双塔楼的风场作用和相互干扰研究较少的情况,首先对方形平面高层建筑的绕流进行数值模拟,并与风洞试验结果及其他数值模拟结果进行比较,验证了计算方法的可靠性;然后采用有限元对梯形平面反对称布置双塔楼在雷诺数较高时的风场进行模拟计算,并与雷诺数相近的圆形平面双塔楼的绕流进行比较,重点研究了平面形状对高层建筑受力系数的影响。结果表明:梯形平面单塔楼的平均阻力系数可以通过矩形平面单塔楼在不同长宽比下平均阻力系数的变化规律来定性判断;随着梯形平面双塔楼间距比的增大,存在受力系数发生明显变化的临界间距比;圆形平面双塔楼之间狭缝流体的动量较大,其受力系数发生变化的间距比小于梯形平面双塔楼受力系数发生变化的间距比;在间距比较大时梯形平面双塔楼的尾流干扰明显,而圆形平面双塔楼的尾流干扰可忽略。研究成果不仅可为该工程的抗风设计提供理论依据,而且可为类似建筑的抗风设计提供参考。

In view of seldom special study on wind field interference of high⁃rise building with two towers in anti⁃symmetric arrangement,the numerical simulation method is adopted,firstly,to simulate the flow around a single high⁃rise building with square plane,and compared with the results of the wind tunnel test and other numerical simulation to verify the feasibility and rationality of the calculation method proposed in this paper.Then,the wind field of a trapezoidal planar two⁃tower high⁃rise building with anti⁃symmetric arrangement is calculated and analyzed by finite element simulation,and the flow around it is compared with that of a high⁃rise building with circular planar twin towers with similar Reynolds number.The influence of plane shape on the force coefficients of high⁃rise building is focused on.The results show that the average drag coefficient of a single tower with trapezoidal plane can be qualitatively judged by the variation law of that of a tower with rectangular plane in different length⁃width ratios.With the increase of the spacing ratio of two towers,the force coefficients change obviously when it reaches the critical spacing ratio.The stream⁃wise momentum of flow in the slit between two circular plane towers is larger,and the spacing ratio when the force coefficient of the cylinder plane changes is smaller than that of two towers with trapezoidal plane.In large spacing ratio,the wake interferences of trapezoidal twin towers are obvious,while that of circular twin towers is negligible.The research results can not only provide theoretical basis for the wind resistance design of this project,but also provide references for the wind resistance design of similar buildings.