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大跨度柱面屋盖结构的风荷载特性具有明显的雷诺数效应,其屋盖几何特征对风荷载雷诺数效应影响较大。为此,以柱面屋盖为研究对象,开展了考虑几何特征影响的雷诺数效应风洞试验,变化几何特征参数包括矢跨比(f/L为1/6~1/2)和长跨比(B/L为1~12),试验雷诺数Re范围为6.90×10~4~1.38×10~6。基于风洞试验数据,分析了模型表面风压分布规律、压力梯度和升阻力曲线等。研究结果表明:柱面屋盖长跨比减小、矢跨比增大会使雷诺数转捩区间的下限值向高雷诺数范围转移,即三维绕流效应使得分离边界层出现转捩滞后现象;当模型长跨比B/L由12减小至1时,雷诺数转捩区间下限值从1.66×10~5逐渐增大至4.14×10~5;当矢跨比f/L由1/3增加至1/2时,转捩区间下限值则从2.48×10~5增大至4.14×10~5;对矢跨比1/6屋盖模型,在试验雷诺数(6.90×10~4~2.48×10~5)范围内无明显雷诺数效应。
The wind load characteristics of the long-span cylindrical roof structure have obvious Reynolds number effect, and the geometrical characteristics of the roof have a greater influence on the wind load Reynolds number effect. For this reason, the cylindrical roof was taken as the research object to carry out the wind tunnel test considering the Reynolds number effect which is influenced by the geometric characteristics. The geometric parameters of the wind tunnel include the ratio of cross-over span (f / L of 1/6 to 1/2) (B / L is 1 ~ 12), Reynolds number Re range of 6.90 × 10 ~ 4 ~ 1.38 × 10 ~ 6. Based on the wind tunnel test data, the distribution of wind pressure on the surface of the model, the pressure gradient and the lift resistance curve are analyzed. The results show that the long-span ratio of the cylindrical roof decreases, and the increase of the sagittal ratio causes the lower limit of the Reynolds number transition to the high Reynolds number range, that is, the three-dimensional flow-around effect makes the separation boundary layer appear transitional lag When the span-to-length ratio B / L of the model decreases from 12 to 1, the lower limit of the Reynolds number transition increases from 1.66 × 10 5 to 4.14 × 10 5. When the ratio of span to span f / L is 1 / 3 to 1/2, the lower limit of transition interval increased from 2.48 × 10 ~ 5 to 4.14 × 10 ~ 5, while for the spanwise 1/6 roof model, the Reynolds number (6.90 × 10 ~ 4 ~ 2.48 × 10 ~ 5) No significant Reynolds number effect.