声激励抑制空腔流激振荡的实验研究  

Experimental Study on Suppression of Cavity Flow Oscillation by Means of Acoustic Excitation

作　　者：罗柏华[1] 胡章伟[2] 戴昌晖 

机构地区：[1]上海大学上海市应用数学和力学研究所 [2]南京航空航天大学空气动力学系

出　　处：《南京航空航天大学学报》1999年第1期1-5,共5页Journal of Nanjing University of Aeronautics & Astronautics

摘　　要：实验研究了声激励对高速外流下矩形空腔振荡流动的抑制效应。实验发现了空腔流激振荡的主导模态随来流速度的敏感变化现象。通过在空腔前缘加纯音声激励，在Ｍ≤０．６的情况下取得了较好的抑制振荡效果。测量了腔口自由剪切层的平均速度型及速度脉动频谱，证实了前缘声激励对自由剪切层内不稳定波的激发作用，探讨了空腔振荡机理及声激励抑制机理。The suppression of high speed cavity flow oscillation by means of acoustic excitation is experimentally studied. It is first found that the major oscillating mode can switch to another frequency mode at small increase of incoming flow speed. With the excitation of leading edge sound wave, considerable reduction of oscillation has been achieved when incoming Mach number equal to or less than 0.6. In addition, the mean velocity profile and the fluctuating velocity in the free shear layer are measured. This verifies that the leading edge acoustic excitation did forced the instability wave in the free shear layer. The physical mechanisms for cavity flow oscillation and its suppression by acoustic excitation have been analyzed.

关 键 词：空腔流动 实验空气动力学 声激励 振荡抑制 

分 类 号：V211[航空宇航科学与技术—航空宇航推进理论与工程]