A Radiation-Hydrodynamics Code Comparison for Laser-Produced Plasmas: FLASH versus HYDRA and the Results of Validation Experiments

Abstract

The potential for laser-produced plasmas to yield fundamental insights into high energy density physics (HEDP) and deliver other useful applications can sometimes be frustrated by uncertainties in modeling the properties and expansion of these plasmas using radiation-hydrodynamics codes. In an effort to overcome this and to corroborate the accuracy of the HEDP capabilities recently added to the publicly available FLASH radiation-hydrodynamics code, we present detailed comparisons of FLASH results to new and previously published results from the HYDRA code used extensively at Lawrence Livermore National Laboratory. We focus on two very different problems of interest: (1) an Aluminum slab irradiated by 15.3 and 76.7 mJ of "pre-pulse" laser energy and (2) a mm-long triangular groove cut in an Aluminum target irradiated by a rectangular laser beam. Because this latter problem bears a resemblance to astrophysical jets, Grava et al., Phys. Rev. E, 78, (2008) performed this experiment and compared detailed x-ray interferometric measurements of electron number densities to HYDRA simulations. Thus, the former problem provides an opportunity for code-to-code comparison, while the latter provides an opportunity for both code-to-code comparison and validation. Despite radically different schemes for determining the computational mesh, and different equation of state and opacity models, the HYDRA and FLASH codes yield results that are in excellent agreement for both problems and with the experimental data for the latter. Having validated the FLASH code in this way, we use the code to further investigate the formation of the jet seen in the Grava et al. (2008) experiment and discuss its relation to the Wan et al. (1997) experiment at the NOVA laser.

High repetition rate exploration of the Biermann battery effect in laser produced plasmas over large spatial regions

“…Ancillary to future measurements that will explore the mechanisms behind the observed return current, and to further interrogate the magnetic field structure in the LPP, we have undertaken a series of simulations using the FLASH code [37] . FLASH is a parallel, multi-physics, adaptive mesh refinement, finite-volume Eulerian hydrodynamics and magnetohydrodynamics (MHD) [38] code, whose high energy density physics capabilities [39] have been validated through benchmarks and code-to-code comparisons [40,41] , as well as through direct application to laser-driven laboratory experiments [42][43][44][45][46][47] .…”

Impact of Electron Transport Models on Capillary Discharge Plasmas

“…For this study, capillary discharge behavior is examined via fully resolved magneto-hydrodynamics simulations performed using the FLASH code. FLASH 24 is a publicly available 26 , parallel, multi-physics, adaptivemesh-refinement, finite-volume Eulerian hydrodynamics and MHD 27 code, whose high energy density physics capabilities 25 and synthetic diagnostics 28 have been validated through benchmarks and code-to-code comparisons 29,30 , as well as through direct application to laserdriven laboratory experiments [31][32][33][34][35][36][37][38] .…”

A novel femtosecond-gated, high-resolution, frequency-shifted shearing interferometry technique for probing pre-plasma expansion in ultra-intense laser experiments

“…b) Electronic mail: feister.7@osu.edu ond scale 5,6 . Characterizing and controlling these preplasma conditions is an integral part of ultra-short pulse experiments 7,8 . Interferometry is a well-known technique that can reveal the plasma electron density profile 9 .…”