Nonlinear Evolution of Jet-Like Spikes from the Single-Mode Ablative Rayleigh-Taylor Instability with Preheating  

作　　者：王立锋 叶文华 范征锋 吴俊峰 李英骏 张维岩 贺贤土 

机构地区：[1]Institute of Applied Physics and Computational Mathematics [2]HEDPS,Center for Applied Physics and Technology,Peking University [3]State Key Laboratory for GeoMechanics and Deep Underground Engineering,China University of Mining and Technology

出　　处：《Plasma Science and Technology》2013年第10期961-968,共8页等离子体科学和技术（英文版）

基　　金：supported by National Natural Science Foundation of China(Nos.10935003,11275031,11075024,11074300 and 11274026);National Basic Research Program of China(No.2013CB834100);China Postdoctoral Science Foundation(Nos.2011M500181,2012T50018)

摘　　要：In this research, the nonlinear evolution of jet-like spikes in the single-mode ablative Rayleigh-Taylor instability （ARTI） in the presence of preheating, is studied numerically. It is demonstrated that the preheating plays an essential role in the formation of jet-like spikes in the nonlinear ARTI. The evolution of jet-like spikes in the ARTI with preheating consists of three stages with distinctly different distinguishing features. In the early stage, the preheating contributes to significantly increase the density-gradient scale length and broaden the velocity profile of the ablation surface, where the former can reduce the linear growth of the ARTI and mitigate the growth of its harmonics. In the middle stage, the ablative Kelvin-Helmholtz instability is dramatically suppressed due to the ablation effects. In the late stage, the jet＇s length （i.e. bubble-spike amplitude） is further increased by the bubble acceleration in the highly nonlinear ARTI, resulting eventually in the formation of jet-like spikes.In this research, the nonlinear evolution of jet-like spikes in the single-mode ablative Rayleigh-Taylor instability （ARTI） in the presence of preheating, is studied numerically. It is demonstrated that the preheating plays an essential role in the formation of jet-like spikes in the nonlinear ARTI. The evolution of jet-like spikes in the ARTI with preheating consists of three stages with distinctly different distinguishing features. In the early stage, the preheating contributes to significantly increase the density-gradient scale length and broaden the velocity profile of the ablation surface, where the former can reduce the linear growth of the ARTI and mitigate the growth of its harmonics. In the middle stage, the ablative Kelvin-Helmholtz instability is dramatically suppressed due to the ablation effects. In the late stage, the jet＇s length （i.e. bubble-spike amplitude） is further increased by the bubble acceleration in the highly nonlinear ARTI, resulting eventually in the formation of jet-like spikes.

关 键 词：Rayleigh-Taylor instability PREHEATING jet-like spike bubble acceleration spike deceleration 

分 类 号：O35[理学—流体力学]