脉冲激光控制高超声速进气道来流捕获

针对高超声速进气道在非设计工况下来流捕获量减少的问题,进行了激光能量沉积控制来流捕获的物理建模和数值模拟,在连续激光能量沉积和脉冲激光能量沉积两种方式下获得了进气道的性能参数。激光功率为15kW时,脉冲重复频率越高,与连续能量注入情况下的进气道性能越接近。脉冲重复频率为100kHz时,计算了脉冲方波占空比为0.1,0.2,0.3和0.4时的进气道流场,结果表明:占空比对进气道性能的影响不大;激光脉宽为500ns时,保持激光平均功率不变,当频率为200kHz和100kHz时,流场结构与连续能量注入时类似,而当频率为500kHz和25kHz时的进气捕获量都有所降低,因此,提高激光脉冲重复频率的同时,降低平均功率,不仅可以有效增大来流捕获,还可降低能耗。

Inflow mass capture control of hypersonic inlet by pulsed laser energy

Aiming at the problem that the inflow mass capture ratio decreases when the hypersonic inlet is under the undesigned state, a physical model is established and numerical simulation is performed on inflow mass capture control by laser energy deposition. The inflow performance parameters are obtained under continuous and pulsed laser energy depositions. When the laser power is 15 kW, a higher pulsed repetitive rate can result in closer inflow performance as that of continuous energy deposition. When the pulsed repetitive rate is 100 kHz, the inlet flow field is simulated in the state that the pulsed square wave duty factor is 0.1, 0.2, 0.3 and 0.4 respectively. The results indicate that the duty factor has little influence on the inlet performance. When the laser pulse duration is 500 ns and the average laser power is fixed, the flow configuration is much close to that of the continuous energy injection under 200 kHz and 100 kHz pulsed repetitive rate. However, the inflow mass capture ratio decreases when pulsed repetitive rate is 500 kHz and 25 kHz. Therefore, with the increasing of the laser pulsed repetitive rate and decreasing of the average laser power, the inflow mass capture ratio increases effectively, and the energy consumption decreases.