多层建筑屋顶风场的数值模拟

Numerical simulation of wind field on the roof of multi-storey building

基于计算流体动力学软件Fluent17.2,以浙江温州大学某栋带女儿墙的多层试验教学楼为研究对象,采用RNG k-ε湍流模型对其进行数值模拟。通过对不同风向角下的数值模拟结果进行对比分析,探究屋顶风场与未受扰来流风场的区别,屋顶不同高度风场的差异,以及不同风向角来流情况下近屋面风场的分布特点、变化规律。结果表明:在离屋面高8m以下,屋顶风速变化剧烈混乱,屋面前沿、中部、后方区域的风速会随高度增加发生变化,并与未受扰来流风场相比存在较大差别;在女儿墙高度1.2m以下,屋面四周区域风速小于中部区域;在离屋面高1.2m~8m时,同一高度屋面前沿区域风速却要大于中部区域及后方区域;在不同的风向角来流下,当来流与建筑迎风面垂直时,屋顶风场沿中线对称分布。本文所得结论可为屋顶各类设备的抗风设计提供一定的参考依据。

Based on CFD software Fluent17.2, the RNG k-ε turbulence model is used to simulate a multi-storey experimental teaching building with parapet in Wenzhou University, Zhejiang Province. By comparing and analyzing the numerical simulation results under different wind direction angles, this paper explores the difference between roof wind field and undisturbed incoming wind field, the difference of wind field at different heights of roof, and the distribution characteristics and variation law of wind field near roof under different wind direction angles. The results show that the wind speed changes violently and confusedly below 8 m from the roof, and the wind speed in the front, middle and rear areas of the roof will change with the increase of height, which is quite different from the undisturbed incoming wind field below the parapet height of 1.2 m, the wind speed around the roof is less than that in the central area;However, when it is 1.2 m~8 m away from the roof, the wind speed in the front area of the roof at the same height is greater than that in the middle area and the rear area;Under different wind direction angles, when the incoming flow is perpendicular to the windward side of the building, the wind field on the roof is symmetrically distributed along the midline. The conclusions reached in this paper provide a reference for wind-resistant design of various kinds of roof equipment.