作　　者： ; ; ;

机构地区： 河南工业大学土木建筑学院

出　　处： 《建筑结构学报》 2016年第S1期19-24,共6页

摘　　要： 基于Fluent软件平台,进行了平滑流场内不同雷诺数情况下半圆球形屋盖结构非定常绕流大涡模拟计算。数值模拟中,以来流平均风速和半圆球屋盖直径定义的3个雷诺数Re为6.6×10~4、3.0×10~5和2.0×10~6。将数值模拟所得屋盖表面平均和脉动风压与已有文献风洞试验结果进行对比,验证了文中数值模拟结果的有效性,并分析了不同大涡模拟参数对数值模拟结果的影响。比较分析了3个雷诺数下半圆球形屋盖结构周围的平均流场和瞬态涡结构分布规律,研究半圆球屋盖结构风荷载的形成机理。结果表明:在保证第1层网格到壁面的无量纲距离y^+≤5.0情况下,进一步加密网格对屋盖表面风压分布影响不明显,而亚格子模型对屋盖表面风压分布影响显著。随着雷诺数的增加,屋盖表面流动分离点逐渐下移,地面上的流动再附点则逐渐前移,上游回流区和下游分离泡均逐渐变小;屋盖表面流动分离区剪切涡形状随雷诺数的增大逐渐变得不规则。 The flow around a hemispherical dome in smooth flow under different Reynolds numbers was numerically simulated employing large eddy simulation (LES) technique based on the commercial code Fluent. Three Reynolds numbers, defined by inflow mean velocity and diameter of the dome, were 6.6×104, 3.0×105and 2.0×106, respectively. The simulated mean and rms wind pressure were firstly verified by comparison with corresponding wind tunnel experimental data. The effect of LES parameters, on the simulation results was also investigated. Statistical flow characteristics and transient vortex structures, under different Reynolds numbers, were then analyzed to further understand the mechanism of wind loads on dome structures. The grid resolution effect on the simulated wind pressure is not as remarkable as SGS model, when the non-dimensional distance between the first grid point and the structure model surface, y+≤5.0. With the increase of Reynolds numbers, flow separation position on the dome moves downstream, while the reattachment position on the ground moves upstream. Meanwhile, both the size of the recirculation zone in front of the dome and the cavity region behind the dome decrease. The shape of shear layer vorticity in the wake region of the dome gets irregular as Reynolds numbers increase. © 2016, Editorial Office of Journal of Building Structures. All right reserved.

关 键 词： 半圆球形屋盖 平滑流场 大涡模拟 雷诺数效应 流场特性

领　　域： [建筑科学]