等离子体激励气动力学探索与展望

等离子体激励气动力学是研究等离子体激励与流动相互作用下, 绕流物体受力和流动特性以及管道内部流动规律的科学, 属于空气动力学、气体动力学与等离子体动力学交叉前沿领域. 等离子体激励是等离子体在电磁场力作用下运动或气体放电产生的压力、温度、物性变化, 对气流施加的一种可控扰动. 局域、非定常等离子体激励作用下, 气流运动状态会发生显著变化, 进而实现气动性能的提升. 国际上对介质阻挡放电等离子体激励、等离子体合成射流激励及其调控附面层、分离流动、含激波流动等开展了大量研究. 等离子体激励调控气流呈现显著的频率耦合效应, 等离子体冲击流动控制是提升调控效果的重要途径. 发展高效能等离子体激励方法, 通过等离子体激励与气流耦合, 激发和利用气流不稳定性, 揭示耦合机理、提升调控效果, 是等离子体激励气动力学未来的发展方向. 

Exploration and outlook of plasma-actuated gas dynamics

Plasma-actuated gas dynamics is an inter-discipline that concerns both the force and flow characteristics of an object submerged in flow, and the internal flow characteristics under the interaction of plasma actuation and flow, thus standing in the frontier of aerodynamics, gas dynamics, and plasma dynamics. Plasma actuation is a controllable disturbance imposed on the flow by either the collective motion of charged particles under electro-magnetic force or the pressure, temperature, and property variation produced by gas discharge. Affected by the local unsteady plasma actuation, the status of gaseous flow will change remarkably, which leads to a potential improvement of the aerodynamic performance. There have been tremendous investigations on surface dielectric barrier discharge plasma actuation, plasma synthetic jet actuation, as well as their interactions with boundary layer flow, separate flow, and shock-dominated flow. A systematic review of these investigations leads to the conclusion that there exists a strong coupling effect between plasma actuation and the modulated flow, and plasma shock control is a key to improving the control authority. Future researches should be directed towards the development of highly efficient plasma actuation, excitation, and leverage of flow instabilities, revealing coupling mechanism, and improvement of control effect.