The numerical simulation of flow around a square-section building
方形截面建筑绕流特性的数值模拟研究

摘要

方形截面是最常见的建筑截面形式之一，分析和明确方形截面建筑绕流特性和表面风荷载是十分必要的。本文对比了四种网格方案，并基于最优方案确定方形截面建筑的平均阻力系数、脉动升力系数、斯托洛哈数及风压分布。结果表明：当近壁面网格无量纲距离小于1时，大涡模拟方形建筑绕流满足精确性要求。方形建筑的平均阻力系数为2.269，脉动升力系数为1.428，斯托罗哈数为0.131。建筑的平均风压系数和脉动风压系数在迎风面转角处发生突变。迎风面平均风压系数为正值，脉动风压系数最小；侧立面和背立面平均风压系数为负值，脉动风压系数在侧立面达到最大值。

Abstract

Square cross-section is one of the most common forms of building cross-section. It is necessary to analyze the flow characteristics and surface wind loads of square-section buildings. In this paper, four grid schemes are compared, and the mean drag coefficient, fluctuating lift coefficient, strouhal number and wind pressure distribution are determined based on the optimal scheme. The results show that when the dimensionless distance of the grid near the wall is less than 1, the accuracy of the large eddy simulation of the flow around a square building is satisfied. The average drag coefficient of the square building is 2.269, the fluctuating lift coefficient is 1.428, and the strouhal number is 0.131. The mean and fluctuating wind pressure coefficients of the building change abruptly at the corner of the windward surface. The mean wind pressure coefficient of the upwind face is positive, and the fluctuating wind pressure coefficient is the smallest; the mean wind pressure coefficient of the side elevation and the back elevation is negative, and the fluctuating wind pressure coefficient reaches the maximum value in the side elevation.