大气层不同高度气压对等离子体射流激励器性能影响的研究

Effect of Flight Altitude on Plasma Synthetic Jet Performance:An Experimental Simulation Study

为将等离子体射流应用于大气层中的飞行器进行流动控制,对火花放电等离子体合成射流激励器,搭建了一套模拟不同大气层高度气压的真空实验系统,通过改变实验容器内的气压来模拟不同的大气层高度,利用动态压力传感器测量激励器射流出口的压力变化,得到激励器出口射流速度。分别对两个不同结构参数的两电极火花放电等离子体射流激励器进行了实验研究。实验结果表明,随着大气层高度的增加,火花放电等离子体合成射流的峰值速度不减反增;在0~10000m高度之间,射流峰值速度随高度大致成线性关系变化;大气层高度每增加1000 m,射流峰值速度增大15%~25%;在10000 m高度左右,高空射流峰值速度大约是地面的两倍。研究表明,在不同的大气层高度下,加载电压幅值、频率、占空比对激励器性能的作用规律与在地面常压下的作用规律相似。

The flow field,around the plasma synthetic jet at different flight-altitudes,was experimentally simulated with the lab-built test platform,comprising the pressure generator,plasma jet actuator,sensors and control units.The influence of the low atmospheric pressure on the plasma jet velocity was investigated.The results show that the low atmospheric pressure has a major impact.To be specific,as the pressure decreased(or the flight-altitude increased),the peak jet-velocity was increased,instead of being decreased;in 0~10,000 m range,the peak jet velocity linearly increased,at an increase-rate of about 15%to 25%for every 1,000 m height increase;at 10,000 m,the peak jet-velocity was two times as fast as that at the ground.As expected,the low atmospheric pressure little affected the performance and operation conditions of the plasma-jet actuator,including the loading voltage amplitude,frequency and duty cycle.