脉冲数目和重复频率对纳秒激光推进的影响  

Effect of laser pulse number and repetition frequency on nanosecond laser propulsion

作　　者：陈豪[1] 石磊[1] 马丽华[1] 彭志明[2] 徐志燕[1] 乔忆炜[3] 

机构地区：[1]空军工程大学信息与导航学院 [2]中国人民解放军95107部队 [3]空军工程大学航空航天工程学院

出　　处：《红外与激光工程》2013年第9期2403-2408,共6页Infrared and Laser Engineering

基　　金：国家自然科学基金(61108068)

摘　　要：以抛物形点聚焦激光推进器模型为研究对象，数值模拟了脉冲重复频率在2-50Hz范围内吸气式多脉冲纳秒激光推进的流场演变过程，分析了脉冲数目和重复频率对推进性能的影响。结果表明：随着脉冲数目的增加，喷管内气体密度减小、温度升高，导致平均冲量耦合系数下降，但纳秒脉冲激光作用获得的平均冲量耦合系数明显高于微秒脉冲激光；相同脉冲数目条件下，随着脉冲重复频率的增大，流场恢复时间缩短，使得流场状态不能及时恢复，导致平均冲量耦合系数下降，其中脉冲重复频率f≥10Hz时的下降趋势明显大于f≤10Hz。The parabolic point focusing thruster model was adopted as research object. The development process of flow field of air-breathing nanosecond laser propulsion with pulse repetition frequency of 2- 50 Hz was numerically simulated, and the Effect of nanosecond laser pulse number and pulse repetition frequency on performance of laser propulsion was analyzed. The results indicate that with the increase of pulse number, the average impulse coupling coefficient decreased due to the reducing air density and increasing temperature. The average impulse coupling coefficient with nanosecond laser is significantly higher than that with microsecond laser, though. With the same pulse number, when the pulse repetition frequency increased, the flow field had less time to recover, leading to the decreasing average impulse coupling coefficient, and the decreasing trend is much more clear in pulse repetition frequency of f≥ 10 Hz than in f≤ 10 Hz.

关 键 词：激光推进 纳秒激光 脉冲数目 脉冲重复频率 平均冲量耦合系数 

分 类 号：TN249[电子电信—物理电子学] V439[航空宇航科学与技术—航空宇航推进理论与工程]