板式建筑表面风压系数模拟分析

Simulation analysis on surface wind pressure coefficient of plate type building

建筑风压系数(Cp)是建筑工程中的一个重要参数,主要用于采暖和制冷负荷计算、通风设计和结构风荷载设计。合适的自然通风能给室内带来清洁新鲜的空气,而风压会直接影响室内空气流动情况。采用CFD软件对板式建筑的室外绕流进行数值模拟研究,获得建筑表面风压系数分布规律。研究结果表明:在一列多排建筑中,后排建筑迎风面风压系数分布遵从'两边大中间小'的原则,并且随着所处排数的增加,其数值越来越大,而后排建筑背风面风压系数分布方式和数值与迎风面完全相反;在一列两排建筑中,后排建筑距前排建筑越远,其迎风面风压系数也越来越大。随后利用建筑后方存在的平面气流涡旋及纵向的回流区长度,对风压系数分布的形成原因做了一定的解释,为建筑设计人员提供参考。

Building wind pressure coefficient(C_p)is an important parameter in building engineering.It is mainly used for heating and cooling load calculation,ventilation design and structural wind load design.Proper natural ventilation can bring clean and fresh air to the room,and wind pressure will directly affect the flow of indoor air.The CFD software was used to simulate the outdoor flow around the slab building,and the distribution law of wind pressure coefficient on the surface of the building was obtained.The results show that the wind pressure coefficient distribution in back row buildings in a row of multi row buildings follows the principle of'both sides of big middle and small',and as the number of rows increases,the value of wind pressure coefficient is larger and larger,and the wind pressure coefficient distribution pattern and value of back air back surface are completely opposite to the windward surface in a row of two rows of buildings.The farther the rear row buildings are from the front row,the higher the wind pressure coefficient on the windward side.Then makes use of the plane airflow vortex in the rear of the building and the length of the longitudinal reflux area,and gives a certain explanation to the cause of the distribution of the wind pressure coefficient,which provides the reference for the architectural designers.