Study of flux limiter using Fokker–Planck and fluid simulations of planar laser-driven ablation

Abstract

The dependence of flux limiters (f ) on laser intensity is investigated by Fokker-Planck (FP) and fluid simulations including laser heating, electron transport and ion hydrodynamics. The planar laser-driven ablation processes are simulated by the FP and fluid code, respectively, where f is obtained according to the match of ablation surfaces between them. It is found that a constant flux limiter in time is applicable in the simulations when laser intensity (I ) is below ∼10 15 W cm −2 . When I > 10 15 W cm −2 , a time-dependent flux limiter is required. The match of corona temperatures computed by the fluid and FP code is also investigated as I increases. It is found that corona temperatures cannot agree well with each other at laser intensities above ∼5 × 10 14 W cm −2 due to the occurrence of a temperature jump near the critical surface in fluid simulation.

Formation of jet-like spikes from the ablative Rayleigh-Taylor instability

“…5 In this paper, we choose a preheating profile with a ¼ 8.6 and b ¼ 1.6. It should be mentioned here that the form of the preheating function f(T) is consistent with that of Fokker-Planck calculations, 13 and the free parameters a and b are determined empirically by comparing the simulation results with that from the corresponding experiment, theory, and/or simulation. Other heatconduction models with preheating effects can also be used.…”