活塞式合成射流技术及其应用研究

设计了活塞式合成射流激励器,研究了合成射流特性及其影响因素,并在高速风洞中开展了合成射流应用于空腔流场气动噪声抑制的试验研究。研究结果表明:合成射流激励器设计合理,能够得到较高速度的射流,正向射流速度极值约160m/s;合成射流频率与激励器激励频率一致;激励器频率、活塞行程以及射流出口形状等参数会对合成射流速度极值产生明显影响;合成射流速度对射流出口厚度变化不敏感;该方法对空腔流场气动噪声的抑制效果与马赫数关系密切,跨声速条件下,采用该方法进行流动控制能够改善空腔流场的气动声学环境,而超声速时该流动控制方法基本失效。

Investigation on piston-typed synthetic j et technology and its application

A piston-typed actuator system is designed to study the characteristics and influence factors of synthetic jet.An experiment is conducted in the high speed wind tunnel to investigate the effect of synthetic jet on aero-acoustic noise suppression of the cavity flow field.Results indi-cate that the synthetic jet actuator is reliable and reasonable,which can produce very high speed jet with the maximum of plus velocity reaching about 160m/s.The frequency of the generated synthetic jet is consistent with the actuator excitation frequency.Some factors,such as the fre-quency of the actuator,the distance of the piston stroke and the shape of the jet exit,may exert great influence on the synthetic jet velocity.Synthetic jet characteristics are insensitive to the thickness of the jet exit.The aero-acoustic noise suppression effect of this flow control method on the cavity flow field depends strongly on the Mach number.Aero-acoustic environment of the cavity can be improved by using synthetic jet as a flow control method at transonic speed.But it is basically ineffective at supersonic speed.