雷暴冲击风风洞设计及流场测试

鉴于雷暴冲击风试验装置的特殊性以及与低速直流风洞的共通性,参考低速直流风洞的设计方法设计完成了试验装置的洞体结构,并制作了具有调节功能的平板来模拟地面.通过调节平板,该装置能够同时改变冲击风强度、直径、射流高度、入射倾角等冲击风参数.试验测得稳态条件下射流口下竖向风速分布,以及沿竖向分布和水平分布的水平风速,研究了水平距离、高度及冲击风参数的影响.研究结果表明:最大水平风速出现的高度与其水平位置有关;射流速度V_(jet)与射流直径D_(jet)在一定范围内对试验结果影响不大;射流高度h与入射倾角α对冲击风的流场有明显影响.

Wind Tunnel Design and Steady Flow Field Measurement for Thunderstorm Downburst Experiment

Thunderstorm downburst wind tunnel has the particularity and the intercommunity with a low-speed uniflow wind tunnel. A wind tunnel for thunderstorm downburst was well designed by taking into account the low-speed uniflow wind tunnel design criteria, andan adjustable plate was made to simulate the ground. By adjusting the plate, the device is able to regulate the downburst parameters, such as the wind intensity, diameter, jet height, inclination angle. Both vertical wind velocity under the jetand horizontal wind velocity profiles along the height and horizontal distances were measured. Results indicate that the height of maximum horizontal wind velocity is correlative with the horizontal position. The downburst intensity and jet diameter have rather small effects on the test results in a certain range. Nevertheless, the jet height and obliquity can affect the flow field of downburst significantly.