可压流条件下凹腔驻涡流动试验

针对几何因素和气动因素对凹腔驻涡流动的影响进行了研究.试验研究了改变凹腔的高长比、射流孔位置和主流进气角度等对凹腔驻涡流动的影响,研究了改变主次流进口流速等气动因素对凹腔流动的影响.总压损失采用总压探针测量,速度场采用粒子图像测速仪(PIV)测量.试验结果表明:①两股射流在中部和底部喷射时均能产生大尺度涡结构,在中部喷射时产生一对旋向相反的涡对,在底部喷射时产生单涡.②在中部喷射情况下,增加主流马赫数和主流进气角度,凹腔上部空间的涡度增强.③主流进口马赫数增加,试验件的总压损失显著增加. 

Experimental study on compressible flow in trapped vortex cavity

The effect of geometry and aerodynamic factors on the flow in trapped vortex cavity was evaluated.The effect of geometry was analyzed by altering the ratio of height to length(H/L) of the cavity,injection position and main-flow inlet angle;the impact of aerodynamics was analyzed by varying main-flow and second inject flow inlet velocity.Total pressure loss was measured by total pressure probe,and the velocity field was measured by particle image velocimetry (PIV).The results reveal that:(1) When the position of the injection holes is in the bottom or the middle position,large scale vortexes can be formed in the trapped vortex cavity.A couple of opposite swirling vortexes are formed in the middle position;and only a single vortex can be formed in the bottom. (2) For the middle injection configuration, increasing the main-flow mach number and inlet angle can enhance the vortex intensity in the upside of the cavity. (3) The total pressure loss increases apparently with the growing main-flow inlet Mach number.