超声速冲击射流的PIV实验研究  

PIV experimental research on supersonic impinging jet

作　　者：姚朝晖[1] 侯修洲[1] 郝鹏飞[1] 

机构地区：[1]清华大学航天航空学院,100084

出　　处：《实验流体力学》2007年第4期32-35,共4页Journal of Experiments in Fluid Mechanics

基　　金：国家自然科学基金(10572074)

摘　　要：冲击射流广泛应用于短距、垂直起降飞行器(SVTOL)等航空航天领域,然而却伴随着流场与噪声等诸多方面的问题,笔者采用PIV(粒子图像测速)技术对超声速冲击射流的流场结构和涡结构进行了深入研究。实验发现在不同的冲击工况下,冲击射流流场结构呈轴对称和螺旋结构,其瞬时流场的主涡结构也有类似特征,脉动流场在瞬时流场主涡结构的基础上会附加与主涡旋转方向相反的次涡结构,在对称和螺旋两种模态下,由于涡结构的影响,冲击射流的近壁速度存在较强的脉动。Impinging jets widely exist in many engineering fields, such as a short take-off and vertical landing （SVTOL） aircraft, as well as air nozzle etc. In this paper, vortex structures and flow patterns were studied by PIV （Particle Image Velocimetry） technique. Two flow modes were found out at different impinging cases, one is axisymmetric mode and another is helical mode. The flow modes may be caused by main vortex structures in instantaneous velocity field. In the fluctuating velocity field, there are second vortex structures with reverse swirling relative to the main vortex. For both flow modes, there are stronger fluctuation velocities near the wall, caused by vortex structures.

关 键 词：冲击射流 PIV 流动模态 涡结构 

分 类 号：O358[理学—流体力学]