分段吹气高层建筑的减阻性能数值研究  

Numerical investigation of the drag-reduction properties of a high-rise building controlled by subsection blowing

作　　者：郑朝荣[1] 张耀春[1] 

机构地区：[1]哈尔滨工业大学土木工程学院,黑龙江哈尔滨150090

出　　处：《空气动力学学报》2010年第4期385-392,共8页Acta Aerodynamica Sinica

基　　金：国家自然科学基金重大项目(59895410)

摘　　要：为减小高层建筑的风致阻力,改善结构的抗风性能,本文采用CFD方法研究了分段吹气高层建筑模型的风荷载减阻性能,分析了侧风面和竖向开孔位置、吹气孔高度hi和吹气速度Vci等参数对减阻性能的影响。结果表明:孔洞位于离侧风面前缘3%宽度时模型的减阻性能优于其它侧风面开孔方案;分段吹气模型的最佳竖向开孔位置发生在0.425m高度处;保持Vci不变时,增加hi使得模型顺风向的阻力折减系数和基底弯矩折减系数增大,且风压减阻效率随hi的增加而减小并逐渐趋近于1.0;当吹气流量或顺风向吹气动量不变时,分段吹气模型的风压减阻效率均不如全高吹气模型。基于最大减阻效率和最小吹气功率比较了分段和全高吹气模型的减阻性能,发现后者的减阻性能优于前者,然而对于某些考虑局部风压的折减,我们可在高层建筑中上部设置吹气装置来改善其局部风压特性。最后,拟合了减阻效率(ηDR和ηMR)关于吹气孔中心高度、hi和Vci的经验公式,为分段吹气控制的应用提供参考。In order to reduce the wind-induced drag and improve the wind-resistance performance of a high-rise building,the subsection blowing control was proposed to investigate the drag-reduction property through numerical simulation.Effects of the slot location on side face and along height,slot height（hi） and blowing velocity（Vci） on the drag-reduction performance were analyzed.It showed that the drag-reduction property was optimal when the slot located at 3%B（B is breadth of the side face） away from leading edge of the side face,and simultaneously,the optimal slot location along height happened at the height of 0.425m.When hi was increased,coefficient of drag reduction（CDR） and coefficient of base moment reductin（CMR） would increase under the same Vci,and their efficiencies（ηDR and ηMR） would decrease until 1.0.ON the other hand,the efficiencies of drag reduction would be less than 1.0 under the same blowing fluxes or along-wind blowing coefficient of momentum.Based on the maximal drag-reduction efficiencies and the minimal power consumed,the drag-reduction properties of the subsection blowing models and all-height blowing model were compared,and it showed that the latter was superior to the former.However,the subsection blowing was still practical,because it could be placed on upside of the high-rise buildings to improve their local wind-pressure characteristics.Lastly,formulae of the ηDR and ηMR versus the slot center along height,hi and Vci were regressed to be referred for practical application of the subsecton blowing control over high-rise buildings.

关 键 词：高层建筑 分段吹气控制 风荷载 减阻效率 吹气功率 

分 类 号：TU973.213[建筑科学—结构工程]