低矮房屋瞬态内压的风洞试验研究

设计一种新的试验方法模拟低矮房屋模型的门窗突然开启过程,在边界层风洞中采用高速同步压力扫描系统对模型开孔的瞬态内压响应进行了试验研究,发现了有别于已有试验研究结论的结果并由内压传播理论所定性验证。试验考虑了开孔率和背景孔隙率对风致瞬态峰值内压的影响,结果表明:门窗突然开启的过冲比(定义为瞬态峰值内压系数和稳态峰值内压系数之比)随开孔率的增大而增加,对于气密性较好的房屋由试验得到的过冲比在1.17～1.34之间,而理论计算的过冲比则更大,相应稳态峰值内压随开孔率的变化相对较小。过冲比随背景孔隙的增大而下降,当背景孔隙率达到0.2%时,瞬时过冲现象消失。

A wind tunnel study of the transient internal pressure of a low rise building

A new experimental approach was applied in a wind tunnel experiment using a high speed synchronous multi-pressure scanning system to study the transient response of the wind-induced internal pressure in a low rise building when a sudden opening appears.The result is quite different from the previous studies,and is qualitatively verified by numerical solution of the internal pressure propagation.The effects of the opening ratio and background porosity factor(Pf) on the peak value of the transient internal pressure were considered in the test.The results show that the overshooting ratio(or defined as the ratio of the peak value of the transient internal pressure to that of the steady internal pressure) increases significantly with the increase of the opening ratio.For a building in excellent air tightness,the present test found Or generally monotonously increase from 1.17 to 1.34 in the tested opening ratio,and the numerical calculation predicts that the real overshooting effect may more significant than that of present test result.The effect of the opening ratio on the steady internal pressure is relatively small.For the effect of Pf,the results show that Or decrease with the increase of Pf,and the overshooting phenomena disappear when Pf is greater or equal to 0.2%.