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arXiv · 1703.10708

Nonlinear Fluid Simulation Study of Stimulated Raman and Brillouin Scatterings in Shock Ignition

L. Hao·R. Yan·J. Li·W. D. Liu·C. Ren
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Abstract

We developed a new nonlinear fluid laser-plasma-instability code (FLAME) using a multi-fluid plasma model combined with full electromagnetic wave equations. The completed one-dimensional (1D) version of FLAME was used to study laser-plasma instabilities in shock ignition. The simulations results showed that absolute SRS modes growing near the quarter-critical surface were saturated by Langmuir-wave Decay Instabilities (LDI) and pump depletion. The ion-acoustic waves from LDI acted as seeds of stimulated Brillouin Scattering (SBS), which displayed a bursting pattern and caused strong pump depletion. Re-scattering of SRS at the 1/16th-critical surface was also observed in a high temperature case. These results largely agreed with corresponding Particle-in-Cell simulations.

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L. Hao, R. Yan, J. Li, W. D. Liu, C. Ren. 2017-03-30. Nonlinear Fluid Simulation Study of Stimulated Raman and Brillouin Scatterings in Shock Ignition. https://doi.org/10.1063/1.4989702

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