武器舱气动噪声主动流动控制技术风洞试验研究

针对飞机弹舱高强度气动噪声、内埋武器分离安全性等问题，以高速风洞动静态压力测量技术为研究手段，开展了基于脉冲射流激励器（Powered Resonance Tubes，PRTB）的武器舱气动噪声抑制技术试验研究。试验结果表明，试验模型具有典型的开式空腔流动特点，武器舱内部非定常流动引起的声载荷可达到150dB。PIV 试验结果研究表明空腔前缘布置主动脉冲射流激励器对剪切层施加激励，会改变武器舱上部剪切层的流动特性，对这种高强度的声载荷起到一定的抑制作用。

Wind tunnel test research on weapon bay cavity active flow control for acoustic

An experimental investigation is conducted in a high speed wind tunnel to suppress acoustic resonance.Conventional leading edge mass blowing actuator are used to disturb cavity flow.Detailed static-pressure and fluctuating-pressure measurements are obtained on the cavity walls to determine the effects on cavity flow characteristics.Wind tunnel test based analysis of the suppression of dynamic loads on the walls of a complex weapon bay using leading edge mass blowing is presented.The unique aspect of the concepts discussed here is the very low mass flow rates used to achieve significant suppression.The simulation results are used to gain insight into the mechanism governing the effectiveness of these jets.The PRTB are applied to a deep (L/D =4.5)cavity at transonic conditions of Mach 0.8.The experimental results show excellent agree-ment with experiments showing an overall reduction of the noise levels of the order of 5 dBs with the control concepts.The primary mechanism of reduction is the break-up of the spanwise coher-ence in the shear layer into smaller vortical structures thus reducing the shear layer flapping and leading to a smaller imprint on the wall pressures.