等离子体能量沉积控制高超声速气动力研究

Research on Hypersonic Aerodynamic Force Control by Arc Plasma Energy Deposition

主动流动控制技术具有响应快、结构简单、使用灵活等优点,在航天器设计中具有广阔的应用前景。本文开展了等离子体能量沉积控制高超声速激波的风洞试验,试验模型为平板-斜坡组合模型,来流马赫数为6。采用高速纹影成像技术获取了平板两对电极间产生的等离子体能量沉积对斜坡诱导激波的控制效果,并通过求解带能量源项的雷诺平均Navier-Stokes方程模拟了能量沉积作用下的流场特性及参数分布。试验结果表明,由于等离子体能量沉积的热效应,其可在平板壁面处诱导压缩波,并形成相对可持续的等离子体层,该等离子体层与高超声速斜激波相互作用时导致了激波弱化。数值计算结果表明,由于激波弱化,斜坡压缩面被等离子体层覆盖的区域压力减小,同时引起模型气动力显著变化。当能量沉积的瞬时功率为4000W时,阻力减小率为55.4%,俯仰力矩变化率为6.9%,而升力变化不明显。研究发现,在等离子体能量沉积的控制下,斜激波的再附点沿斜坡压缩面向上移动,且能量沉积的瞬时功率越大,等离子体层越厚,激波再附点移动的距离越大,相应的阻力减小率越大。最后,阐明了等离子体能量沉积改变模型气动力/力矩的控制原理。

Active flow control technology has the advantages of fast response,simple structure and flexible operation.It has a great potential application in spacecraft design.In this paper,the Ma 6 wind tunnel experiment has been carried out for hypersonic oblique shock control by using plasma energy deposition.A flat plate model combined with a ramp is used.The control effect of plasma energy deposition between two pairs of electrodes on hypersonic oblique shock is obtained with high-speed schlieren imaging technology.The flow field characteristics and parameters under the energy deposition are simulated by solving Reynolds averaged Navier-Stokes equations with an energy source term.The experimental results showed that due to the thermal effect of plasma energy deposition,compression waves are induced at the plate wall and a relatively sustainable plasma layer was formed,which weakened the hypersonic oblique shock;The numerical results showed that due to the weakening of the shock wave,the pressure on the ramp wall covered by the plasma layer is decreased,and the aerodynamic force of the model is changed significantly.When the instantaneous power of energy deposition is 4000W,the wave drag reduction rate is as high as 55.4%,the change rate of pitch torque is 6.9%,and the lift change is not obvious.It is found that under the control of plasma energy deposition,the reattachment point of oblique shock moves upward along the compression surface of the ramp,and the greater the instantaneous power of energy deposition,the thicker the plasma layer,and the greater the corresponding wave drag reduction rate.Finally,the control principle of hypersonic aerodynamic force/torque with plasma energy deposition is clarified.