论文部分内容阅读
激光推力器在高空环境下飞行不可避免地会受到来流的影响,而其入口状态直接影响激光聚焦点火之前的定常流场状态,从而影响推力器的推进性能。在来流马赫数为5的条件下,对某种吸气式推力器模型的入口在打开、关闭以及半开3种状态下的内外流场演化过程进行了数值模拟。结果表明:入口打开时,轴向阻力低于同工况下入口关闭和半开的情况;入口关闭时,聚焦区的激波传播速度明显增加,正推力峰值明显增大,抵消了入口关闭带来的额外负推力;入口半开时,正推力较入口关闭没有得到有效提高,轴向阻力较入口打开却大幅增加,导致其冲量耦合系数最低,推进性能最差。通过计算和分析预测,入口构形的改进设计可大幅度提高来流情况下推力器的推进性能,对入口构形优化还需进行大量工作。
Laser thrusters flying at high altitude will inevitably be affected by the incoming flow, and its entrance state directly affects the state of steady flow field before the laser focusing ignition, thus affecting the propulsion performance of the thruster. Under the Mach number of 5, the evolution of the inlet and outlet flow field of a certain aspirated thruster model under open, closed and half-open state are numerically simulated. The results show that when the inlet is open, the axial resistance is lower than that of the inlet closed and half opened under the same conditions. When the inlet is closed, the shock wave propagation speed in the focal area increases obviously and the positive thrust peak increases obviously, When the entrance is half-open, the positive thrust is not effectively increased compared with the entrance closed, but the axial resistance is greatly increased compared with the entrance opening, resulting in the lowest impulse coupling coefficient and the worst propulsion performance. Through the calculation and analysis of prediction, the improved design of the entrance configuration can greatly improve the propulsion performance of the thrusters under the condition of flow, and a great deal of work needs to be done on the optimization of the entrance configuration.