激光烧蚀固体碳氢材料的离子组分分离研究  

Separation of ion component from solid hydrocarbon materials by laser ablation

作　　者：陆云杰 陶弢 赵斌[2,3] 郑坚[1,3] Lu Yun-Jie;Tao Tao;Zhao Bin;Zheng Jian(Department of Plasma Physics and Fusion Engineering,University of Science and Technology of China,Heifei 230026,China;Department of Mathematics and Physics,Nanjing Institute of Technology,Nanjing 211167,China;IFSA Collaborative Innovation Center,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]中国科学技术大学等离子体物理与聚变工程系,合肥230026 [2]南京工程学院数学与物理系,南京211167 [3]上海交通大学,IFSA协同创新中心,上海200240

出　　处：《物理学报》2023年第7期277-286,共10页Acta Physica Sinica

基　　金：中国科学院战略性先导科技专项(批准号:XDA25010200,XDA25050600);中央高校基本科研业务费专项资金(批准号:WK2140000014)资助的课题.

摘　　要：本文从双离子组分等离子体的Landau-Fokker-Planck方程出发,通过Chapman-Enskog方法约化得到离子输运方程,求得双离子组分等离子体的离子输运系数,给出了计及离子扩散的完备离子流体方程;再结合一维辐射流体力学程序Multi-1D模拟得到的烧蚀层的宏观状态,研究了激光烧蚀固体碳氢材料时的组分分离现象.计算结果显示,离子组分分离对等离子体流体演化的影响小,基本可以忽略;但对于敏感依赖于离子组分的其他物理过程,如汤姆孙散射,离子组分分离的影响显著,这意味着研究激光等离子体相互作用时,离子组分分离必须予以考虑.Plasma usually consists of multiple ion component.Ion-component separation occurs in various conditions,and profoundly affects the plasma dynamic evolution.In this work,ion-component separation in two-ion-component plasma is investigated in the hydrodynamic condition.Starting from the Landau-Fokker-Planck equations of two-ion-component plasma,the ion transport equations are reduced through the Chapman-Enskog approach.The transport equations are then transformed into a set of linear algebraic equations and solved by expanding the perturbed ion distribution functions into the series of Sonine polynomials.The diffusive ion mass flows with inclusion of baro-diffusion,thermo-diffusion and electro-diffusion are thus obtained.With these efforts,the complete ion fluid equations are presented,which can be used to describe the processes of ion-component separation.We evaluate ion-component separation in the case of a solid CH plate target ablated with a laser pulse,by solving the ion diffusion equation with the hydro states output from the one-dimensional radiative hydro code Multi-1D.The simulation results show that ion-component separation mainly occurs around ablation front and under-dense region,and that the effect of ion-species separation on plasma hydrodynamic evolution is minor and can be neglected.For those physical processes sensitive to ion concentration such as Thomson scattering,however,the effect of ion-component separation is significant,which means that ion-component separation should be included in the study of laser plasma interaction.

关 键 词：等离子体输运过程 组分分离 激光烧蚀 辐射流体模拟 

分 类 号：TL334[核科学技术—核技术及应用]