摘要
以一种新型上翘式弧形火车站雨棚为研究对象,通过风洞试验和数值模拟两种方式研究了该新型结构的风荷载特性。通过大比尺风洞测压和测力试验,研究了该雨棚表面风压分布规律和在不同风攻角作用下雨棚的三分力系数变化特征。试验结果表明,由于雨棚的上翘构造,使得迎风面上表面的负压变大,下表面的正压变大,风荷载作用进一步加强;风荷载分布对风向角较为敏感,0°风向角为最不利风向角。通过CFD数值模拟方法计算了不同比尺下结构的三分力系数,并与风洞试验结果进行对比,研究了雷诺数对该雨棚三分力系数的影响。该结构并非典型流线型结构,由于上翘的影响,存在明显的流体分离和再附,具有钝体绕流特性,当选用1∶10和1∶15大比尺时,三分力系数与原型相差较小。因此,对该类结构选择大比尺模型进行风洞试验研究是非常必要的。
The properties of wind loads on a new upwarping arc railway station canopy are studied through wind tunnel testing and numerical simulation. First of all, to investigate the surface wind pressure distribution and static load coefficients, wind tunnel tests are conducted for the large-scale model of the new upwarping arc railway station canopy. Testing results show that negative pressure on the upper surface and positive pressure on the lower surface become larger, consequently higher wind loading due to the upwarping structure of the canopy. The wind load on this canopy is sensitive to wind azimuth, and wind azimuth of 0°is the most disadvantageous case. The three-component force coefficients of this canopy in different scales are calculated through CFD numerical simulation and compared with the results of wind tunnel tests, thus the influence of Reynolds number is investigated. The canopy has characteristics of flow around a bluff body, and when the large scale is chosen, such as 1：10 and 1： 15, regarding three-component force coefficients there are very small differences between model and prototype. Therefore,it is very necessary to conduct wind tunnel tests on large-scale models for the new upwarping are railway station canopy.
出处
《四川建筑科学研究》
北大核心
2015年第4期7-11,共5页
Sichuan Building Science
基金
国家自然科学基金资助项目(51278433)
关键词
上翘式
火车站雨棚
大比尺
风洞试验
风攻角
雷诺数
upwarping
railway station canopy
large scale
wind tunnel test
wind attack angle
Reynolds number
