应用等离子体抑制空腔噪声数值仿真研究

空腔在自由来流下将产生强烈的气动噪声，这种噪声会对飞机产生负面作用，需要寻求噪声控制方法抑制空腔噪声。等离子体是一门新兴的流动控制技术，可应用在噪声抑制方面。通过在空腔前缘、后缘以及底面10个不同的位置布置等离子体激励器，研究了等离子体激励对空腔噪声的影响。结果表明：等离子体激励可以降低空腔噪声，声压级最高降低约4 dB；降低了空腔离散噪声的峰值频率；在空腔前缘壁面施加等离子体激励，噪声抑制效果最好。

A Numerical Investigation of Cavity Aerodynamic Noise Control Based on Plasma Actuator

When a free stream flowing over a cavity,intense aerodynamic noise would occur,which can bring negative effect to airplanes,so kinds of cavity acoustic suppression methods should be seek. Plasma is an emerging flow control technology. For this purpose,through situated plasma actuator in ten different locations:cavity leading edge wall,trailing edge wall and bottom floor,the effect that plasma actuator loca-ted position on cavity acoustic was investigated. The simulation result showed that:when plasma actuator was situated reasonably,the cavity acoustic could be reduced,and the sound pressure level reduced could reach up to 4 dB,plasma could reduce the peak frequency of cavity discrete noise;when the plasma actu-ator was placed at the leading edge of cavity,the aerodynamic noise control effect was best.