高速冲击射流流场特性与噪声机理的研究  

Study on flow characteristics and noise mechanics of impinging jet with high speed

作　　者：姚朝晖[1] 何枫[1] 韩标[1] 许宏庆[1] 

机构地区：[1]清华大学工程力学系,北京100084

出　　处：《流体力学实验与测量》2003年第2期84-87,共4页Experiments and Measurements in Fluid Mechanics

基　　金：国家自然科学基金资助项目(批准号:19902009)

摘　　要：利用纹影方法和高速摄影得到了高速冲击射流在不同压比下的流场结构,发现在马赫盘出现之前,冲击射流的流场是整体振荡的;而马赫盘出现之后,冲击射流的流场振荡局限于马赫盘与冲击平板之间,且此时离散频率的冲击单音也明显减弱甚至消失,这意味着马赫盘的形成可一定程度地抑止反馈环的形成。In the paper, flow structures at different pressure ratios are obtained by Schlieren image and high speed camera. It is found that the whole flow field is oscillating at lower pressure ratio. When Mach disk forms in the flow field, the oscillation will only exist between Mach disk and impinging plate. At the same time, impinging tone with discrete frequency will be decreased and even be diminished. From this point, it can be deduced that Mach disk can restrain the formation of feedback loop for discrete frequency impinging tone.

关 键 词：冲击射流 流场结构 马赫盘 反馈环 噪声 自激振动 

分 类 号：O358[理学—流体力学] O422.8[理学—力学]