不带导流板矩形腔流激振荡的幅值特性

Amplitude property about flow induced oscillation o f cavity without flange plate

通过试验，分析、探讨了流激振荡的幅值特性和耦合振荡特性．发现在小迎角下，腔的驻波振荡占优势，其振荡声压级随迎角的增大而增强；在大迎角下，流体动力振荡与腔的驻波振荡发生耦合共振，其耦合振荡的声压级随迎角的增大而减小．耦合振荡的产生有限制条件，即迎角存在下限，流速存在上下限；上限流速随气流迎角的增大而增大．

The paper analyses and inquires into the amplitude property about the flow indu ced oscillation of the cavity without the flange plate by experiments. The follo wing results are valuable: (1)At small attack angle, the sound standing wave re sonance is dominant, and the sound pressure increases with increase of the attac k angle. (2)At large attack angle, the coupling oscillation between fluid dyna mic oscillation and sound standing wave resonance is found out and the oscillati on pressure decreases with increase of attack angle. (3)The formation of the co upling oscillation has criteria. The attack angle has a lower limit. And the fl ow speed has a finite range.