激光水推进的机理研究及参数优化  

Mechanism for water-powered laser propulsion

作　　者：王彬[1] 唐志平[1] 蔡建[1] 胡晓军[1] 

机构地区：[1]中国科学技术大学力学和机械工程系

出　　处：《推进技术》2007年第5期586-589,共4页Journal of Propulsion Technology

基　　金：国家"九七三"项目(61328)

摘　　要：为了研究双层结构靶的激光水推进过程中各阶段能量转移和转化的物理机制,将一个激光脉冲推进过程划分为四个阶段,并针对双层结构靶的特点,提出了"爆炸-连续爆炸推进模型",利用该模型定性解释了实验结果。实验显示,激光水推进得到的冲量耦合系数比其它推进模式高一到两个数量级。定义了金属粒子与水分子单次碰撞的能量传递率κ为表征推进效率的一个参量,计算不同的金属基底材料对应的κ值:A l为96%,Fe为73.6%,Cu为68.8%,该结果与实验得到的Cm值变化趋势一致。通过对模型的分析,得出选择原子量与水分子量接近的金属,可以得到更好的推进效果;并存在一个与基底材料和激光参数对应的水层最优厚度。The propulsion in one laser pulse period was divided into four relative phases. The principles and laws of energy translation and transformation in each phase were investigated separately. A new model named ＂ explosion and continuous explosion propulsion＂ was proposed to describe the character of water-powered propulsion for exotic target. It can determine the nature of the experimental results. Water-powered laser propulsion can generate much higher C than other modes of laser propulsion. A parameter s： is defined to describe the energy transformation rate of one impact between metal atom and water molecule. The κ of Cu, Fe and Al are 68.8% , 73.6% and 96.0% respectively, has the same increasing trend as the trend of Cm using these material as target floor. By investigating the principles, using a metal which has the closest atomic weight with the water molecule as the floor material can lead to better propulsive effect. There is an optimization for thickness which depends on the target floor and the laser parameters.

关 键 词：激光推进 激光水推进^+ 双层结构靶 基板 材料 

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]