基于光路追踪方法的激光交叉束能量转移模型  

Laser crossing-beam energy transfer model based on ray-tracing method

作　　者：李欣[1] 郝亮[1] 

机构地区：[1]北京应用物理与计算数学研究所

出　　处：《强激光与粒子束》2014年第5期136-140,共5页High Power Laser and Particle Beams

基　　金：国家高技术发展计划项目;国家自然科学基金项目(11305014)

摘　　要：提出一种基于几何光路追踪方法并可在流体模拟程序中实现在线计算的激光交叉束能量转移(CBET)耦合模型。借助由激光逆轫致吸收公式引入的泵浦激光功率密度在流体网格尺度上的计算公式,该模型可计算探针激光束中每根光线所携带的能量经过与泵浦激光场相互作用带来的损失(或增加),从而实现激光能量在束间的转移。反复迭代的计算方法解决了由于激光束间能量转移与光线历史相关并且束间强耦合带来的方程求解困难。模型很容易推广到多束激光束两两能量交换的情形,也可用于研究逆轫致吸收和激光等离子体相互作用等物理内容。A new ray-based model of crossing beam energy transfer （CBET） is developed. This model can be used in dy- namic kinetic codes for evaluating CBET in line. By defining laser intensity in grid through inverse bremsstrahlung absorption for mula of laser, every single ray of probe laser beam can obtain （or lose） energy from the intensity of pump laser beam. Since CBET is dependent on the history of every single laser ray and the coupling between probe laser and pump laser is strong, the cou pling equations are difficult to be solved. Calculating iteratively can solve the problem well. This in-line CBET model can be gen- eralized to the situation where there are energy transfers among three or more laser beams easily. Inverse bremsstrahlung absorp- tion and laser plasma interaction could also be involved in the model.

关 键 词：间接驱动惯性约束聚变 激光靶耦合 交叉束能量转移 几何光路追踪 在线耦合计算 

分 类 号：O532.13[理学—等离子体物理]