激光脉冲重复频率对冲量耦合系数的影响

Effect of laser pulse repetition rate on momentum coupling coefficients

设计了触发间隔从100ms到5ms可调的双脉冲触发器驱动TEACO2激光器高压开关,用以模拟激光器不同的输出脉冲重复频率。用该装置精确控制的不同激光脉冲重复频率下,对抛物面型光船模型进行了大气模式激光推进中冲量耦合系数的实验研究。发现冲量耦合系数随着重复频率的增加而下降,而单位时间内光船获得的冲量耦合系数的增量则随着重复频率的增加而增大。初步分析认为,这是由于飞行器内的空气未得到充分的补充造成的。

A double pulse trigger was designed,and the interval of the trigger pulse controlling the TEA laser high voltage switch could be adjusted from 5 ms to 100 ms to simulate different operating repetition rate of the TEA CO2 laser. By this means, the laser repetition rate was accurately controlled. The momentum coupling coefficients for the air-breathing mode laser propulsion were studied with a parabolic light craft model. It was found in the experiment that the momentum coupling coefficients decreased when the laser repetition rate increased, while the increment of the momentum coupling coefficients increased in unit time. The reason might be that the air as the propellant could not be supplied enough for the high laser pulse repetition rate, which would weaken the effect of the propulsion.