Non-linear characteristics of Rayleigh–Taylor instable perturbations

被引：0
作者：
Zhengfeng Fan
Jisheng Luo
机构：
[1] Tianjin University,Department of Fluid Mechanics, School of Mechanics
来源：
Acta Mechanica Sinica | 2008年 / 24卷
关键词：
Inertial confinement fusion; Rayleigh–Taylor instability; Non-linear characteristics; Direct numerical simulation;
D O I：
暂无
中图分类号：
学科分类号：
摘要：
The direct numerical simulation method is adopted to study the non-linear characteristics of Rayleigh–Taylor instable perturbations at the ablation front of a 200 μm planar CH ablation target. In the simulation, the classical electrical thermal conductivity is included, and NND difference scheme is used. The linear growth rates obtained from the simulation agree with the Takabe formula. The amplitude distribution of the density perturbation at the ablation front is obtained for the linear growth case. The non-linear characteristics of Rayleigh–Taylor instable perturbations are analyzed and the numerical results show that the amplitude distributions of the compulsive harmonics are very different from that of the fundamental perturbation. The characteristics of the amplitude distributions of the harmonics and their fast growth explain why spikes occur at the ablation front. The numerical results also show that non-linear effects have relations with the phase differences of double mode initial perturbations, and different phase differences lead to varied spikes.
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页码：143 / 149
页数：6
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