强激光与超音速自由剪切层的相互作用

Interaction of power laser beam with supersonic free shear layer

以波长为10.6μm,半径0.1m,焦距106m的激光束穿过二维超音速自由射流剪切层流场为物理模型,研究了由于辐射加热强激光束对流场的干扰以及激光束穿过流场后光束远场强度的分布。结果表明:由于流场的存在,使光束的远场强度分布产生了较为明显的变化,对于射流出口处不同的马赫数以及出口压力,流场对光场的远场强度分布影响不同;对于没有引起气体介质电离的强激光束,由辐射加热引起的对超音速自由射流剪切层流场的影响可以忽略。

Based on the discussion of the law of the interaction between opticfield and fluidfield, this paper uses the physical model of highenergy laser beam crossing through the two dimension supersonic free shot flow. We obtained density map and OPD map of fluid field and far field distribution of laser beam. We discussed: the disturbance of the fluidfield caused by radiation heating and the changing of laser beam intensity after the beam passing through the fluid field and propagating 2km in the still atmosphere. The results show that there's a distinct influence of fluidfield on opticfield. Also we got that in studying the interaction of supersonic free shot fluidfield with highenergy laser we can neglect the radiation heating when the air is not ionized.