摘要
为了对气液两相介质激光推进技术中雾化水滴的击穿阈值特性进行研究,建立激光诱导下单个水滴微粒的光学击穿模型,计算分析入射功率密度、水滴微粒半径、入射激光波长等相关因素对雾化水滴颗粒击穿过程的影响.结果表明:随入射功率密度的增大,由107 W/cm2上升至1011 W/cm2,击穿位置沿入射反方向移动.随水滴微粒半径的增大,从0到50μm,击穿阈值减小,从35×106 W/cm2下降到2.5×106 W/cm2,击穿位置沿入射方向移动.随激光波长的增大,由0到12μm,击穿位置沿入射反方向移动;当波长较短时(λ<2μm),击穿阈值随波长增大而迅速减小,从25×106 W/cm2下降到5×106 W/cm2.当波长较长时(λ>2μm),波长增大对击穿阈值影响较小.
The optical breakdown model of water droplet induced by laser was established to analyze the breakdown threshold characteristic of atomized water drop in gas-liquid two phase laser propulsion.Some influence factors of laser breakdown process,such as laser density,radius of water drop and wavelength of laser,were discussed.Results show that with the increase of incident power density from 10^7 W/cm^2 to10^11 W/cm^2,the breakdown position moves along the opposite direction of the incident laser.The breakdown threshold decreases from 35×10^6 W/cm^2 to 2.5×10^6 W/cm^2 and the breakdown position moves along the direction of the incident laser with the improvement of the radius of water droplets fromo 0to 50μm.The breakdown position moves along the opposite direction of the incident laser with the increase of the laser wavelength fromo 0to 12μm.The breakdown threshold rapidly decreases from 2.5×10^7 W/cm^2 to 5×10^6 W/cm^2 with the increase of laser wavelength when the wavelength is short（λ〈2μm）,while the breakdown threshold has a little variation when the wavelength is long（λ〉2μm）.
出处
《浙江大学学报（工学版）》
EI
CAS
CSCD
北大核心
2016年第5期949-954,共6页
Journal of Zhejiang University：Engineering Science
基金
国家自然科学基金资助项目(51276169)
浙江省自然科学基金资助项目(LY13E060001)
关键词
雾化水滴击穿模型
激光击穿阈值
击穿位置
laser breakdown of atomized water droplets
breakdown threshold
breakdown position
