大气呼吸模式激光推进数值分析

详细分析了激光击穿空气和激光维持等离子体爆轰波(LSD)的传播机制,基于Navier-Stokes方程建立了考虑湍流、等离子体辐射的流场分析模型,采用有限体积法系统分析了推进器喷管内等离子体冲击波流场的演变规律,研究了单脉冲激光能量大小和脉宽对推进性能的影响。数值仿真中明显捕捉到有关实验中观察到的马赫杆的产生与移动过程;得出了推力和冲量耦合系数随脉冲能量、脉宽的变化关系,计算结果与德国空间中心实验吻合得较好,为脉冲激光器的选择和脉冲参数优化提供了参考依据。

Numerical Analysis of Air-Breathing Mode Laser Propulsion

The laser induced air-breakdown and propagation mechanism of laser sustained plasma detonation(LSD) were analyzed in detail. Based on Navier-Stokes equations,the analysis models considering turbulence and plasma irradiation were established for flow field.And the evolvement of plasma shock wave in thruster was systematically analyzed by the finite volume method.The effects of single pulse energy and width on propulsion performance were described also.The production and transmission process of Mach cone observed in many experiments has been captured in this numerical simulation.The relation between thrust,impulse coupling coefficient and one pulse laser energy,pulse width were gained,which agreed well with the experimental results by Germany Space Center.These numerical results can provide some reference for the pulse laser choice and pulse parameters optimization.