汽车风洞试验段流场的试验研究

以上海地面交通工具风洞中心全尺寸气动声学风洞1：15模型风洞为研究对象，采用三维热线风速仪，测量了该模型风洞内不同工况下试验段内流场的分布情况。通过所测流场内平均速度的分析，了解该模型风洞试验段内气流的定常流动形态，对比典型射流结构进行分析，得到了该开口式低速汽车风洞试验段内喷口处射流剪切层所特有的结构形态；通过对风洞试验段内不同截面处流场内部湍流强度的分析比较，了解了喷口射流剪切层内以及收集口处的湍流强度大小与分布情况。

Test research of the flow field inside the test section of the automotive wind tunnel

Based on the Shanghai Automotive Wind Tunnel Center＇s aerodynamic and aero-acoustic wind tunnel, the 1.15 scaled wind tunnel was built. Three dimensional hot-wire was used to measure flow distribution inside the test section of the wind tunnel under different conditions. By analyzing the average velocity of the airflow, the steady characteristic of the airflow inside test section of the wind tunnel was understood. By compared with a typical jet-flow, the special prism structure of the jet-flow spout out of the nozzle was obtained. Through analyzing the turbulent intensity at the different sections in test section, the distribution and intensity of the turbulance at the nozzle and collectors were understood. This research helps us to have a comprehensive understanding of the flow field inside the test section of open-jet low speed wind tunnel.