交错布局轻型双坡房屋群表面风压特性

摘要

In order to study the surface wind pressure distribution characteristics and wind environment around staggered layout lightweight double slope houses, the fluid dynamics analysis software FLUENT was applied to study the key techniques and parameters, such as domain size, the number of grid and turbulence model, and a numerical wind tunnel model of double slope houses was established based on fluid dynamics principle and atmospheric boundary layer theory.Taking the transverse density coefficient, longitudinal density coefficient and wind direction angle as parameters, the wind pressure distribution characteristics of 60 kinds of numerical wind tunnel conditions on light double slope buildings were studied, the surface wind pressure distribution law of houses under wind-induced interference effect was obtained.Through introducing the interference factor, the disturbed degree of relatively single house in target groups was quantified, and the shape coefficient of houses was obtained.The wind speed of house monitoring points in 90° wind direction angle was calculated, and the outdoor wind environment was evaluated by wind speed ratio index.The results show that the longitudinal spacing of staggered layout houses without interference is 4L (L is the length of house) and transverse spacing without interference is 5B (B is the width of house) in 90° wind direction angle;outdoor wind environment is better when spacing of buildings transverse is 0.5B and longitudinal spacing is 2L-4L.%为了研究交错布局轻型双坡房屋群表面风压特征及周围风环境,基于流体动力学基本原理和大气边界层理论,采用流体动力学分析软件FLUENT,结合风洞试验数据研究计算域大小、网格数量及湍流模型等关键技术与参数,建立了双坡房屋群的数值风洞模型.以横向疏密系数、纵向疏密系数及风向角为参数,运用数值风洞对轻型双坡房屋群进行60种工况的风压分布特性研究,得到风致干扰效应下房屋群表面风压分布规律;引入干扰因子将目标房屋相对单体的受扰程度量化,得到房屋群的风荷载体型系数;计算了90°风向角下房屋间监测点的风速,借助风速比指标对室外风环境进行评估.结果表明:90°风向角下,交错布局群体房屋的纵向无干扰间距为4L(L为房屋长度),横向无干扰间距为5B(B为房屋宽度);房屋群横向间距为0.5B、纵向间距为2L~4L时室外风环境较好.