檐口形状影响四坡低矮房屋屋面平均风压分布规律的数值模拟研究*
- 摘 要
-
（湖南科技大学土木工程学院， 湘潭 411201）
［摘要］为探究典型檐口形状对屋面风压分布规律的影响，基于日本东京工艺大学风洞试验数据，针对四坡低矮房屋采用ANSYS-CFD计算流体力学软件的两种湍流模型展开研究，验证了RNGk ε湍流模型对四坡低矮房屋表面风压研究的可靠性。利用此模型深入研究檐口不同外伸长度与出挑高度对四坡低矮房屋风压影响规律。结果表明：檐口的外伸长度及出挑高度对屋面风压影响明显，当外伸长度不变时，随出挑高度的增大，迎风面风吸力随之增大；当出挑高度不变（出挑高度分别为0.5，1.0m）时，随着外伸长度的增大，迎风面负风压减小；外伸长度为1.5m、出挑高度为1.0m为最有利于房屋表面抗风设计；随外伸长度增大，檐口各区域风压减小，但设置檐口形状2比檐口形状1较有利于房屋表面抗风设计，结论可为台风多发地区低矮民居设计提供建议。［关键词］四坡低矮房屋; 数值模拟; 檐口; 屋面风压中图分类号：TU312+.1 文献标识码：A 文章编号：1002-848X(2015)13-0094-06
Numerical simulation research on the influence of cornice shape on mean wind-pressure distribution law of low-rise hip roofed buildingsDai Yimin, Zou Simin, Liu Ye, Lei Jingmin, Jiang Rongzheng(College of Civil Engineering, Hunan University of Science and Technology, Xiangtan 411201, China)Abstract:Based on the data of wind tunnel test data from Tokyo Polytechnic University to explore the influence of typical cornice shapes on roof wind pressure distribution law, two kinds of turbulence models of computational fluid dynamics software ANSYS CFD were used to study the low-rise hip roofed building to verify the reliability of using RNGkεturbulence model for researching surface wind pressure of low-rise hip roofed buildings. The models were chosen to study the laws of influences of various cornice extended lengths and cantilever heights on wind pressure of low-rise hip roofed building in depth. The results show that cornice extended length and cantilever height have significant influences on roof wind pressure. If the extended length is unchanged, the windward side wind suction increases with the increase of the cantilever height. If the cantilever height is unchanged as 0.5m or 1.0m, the windward side negative wind pressure decreases with the increase of the cantilever height. It is optimum for building surface wind resistance design if the extended length reaches 1.5m and the cantilever height reaches 1.0m. The wind pressure in each area of cornice decreases with the increase of the extended length. The cornice shape 2 is better for building surface wind resistance design than cornice shape 1. The conclusion can provide suggestions for low-rise residential design in typhoon prone region.Keywords:low-rise hip roofed building; numerical simulation; cornice; roof wind pressure
*交通运输部重大科技项目（2011318824140），广西防灾减灾与结构安全重点实验室开放课题（2013ZDK-06），湖南省教育厅（13K088）。作者简介：戴益民，博士，副教授，Email：dymzzy@163.com。
