为了研究激光诱导射流等离子体特性, 了解激光诱导液滴等离子体的发展过程, 基于脉冲激光-液滴同步作用系统, 采用阴影法,观测了激光作用液滴的阴影图像, 取得了液滴在CO2脉冲激光作用下的演化过程数据。对图像进行处理获得了激光诱导液滴等离子体冲击波膨胀范围随时间的变化, 并估算出了产生冲击波的激光能量。结果表明, 空气冲击波的膨胀半径在当前观测时间范围内线性膨胀, 约32%的激光能量用于产生冲击波。空气冲击波的变化规律对激光诱导液态燃料点火的研究提供了一定的参考依据。

In order to study the characteristics and the evolution of laser-induced liquid droplet jet flow plasma, the behaviors of laser-induced liquid droplet plasma were investigated by the shadow method based on laser-droplet interaction system. Time-series images of CO2 laser-induced plasma with liquid droplet were captured. The evolution of air shock wave was obtained and the energy of shockwaves was estimated by theoretical model. The results show that air shock wave occurrs with laser-induced plasma and the radial expansion of shockwaves increases linearly under current time range. In addition, laser energy dissipated in the droplet was estimated to 32% for generating air shockwaves. The characteristics and the evolution of shockwaves generated by laser-induced droplet could provide a reference for laser induced fuel spray ignition.