SPRAY: A smoothed particle radiation hydrodynamics code for modeling high intensity laser-plasma interactions

TL;DR

SPRAY is a novel GPU-accelerated, mesh-free SPH code for simulating complex laser-plasma interactions with high accuracy, addressing limitations of previous methods in high energy density physics.

Contribution

It introduces the first SPH-based radiation hydrodynamics code tailored for high intensity laser-plasma interaction simulations, with a mesh-free ray-tracing scheme and WKB-based laser coupling.

Findings

Demonstrated accuracy with benchmark problems

First SPH application to laser-plasma interactions in high energy density physics

Achieved reliable simulations of laser-target irradiation phenomena

Abstract

Here we report the development of SPRAY, a massively parallel GPU accelerated, smoothed particle hydrodynamics (SPH)-based, radiation hydrodynamics (RHD) code designed specifically for simulating high intensity laser-plasma interactions. When a target is irradiated by an intense laser, highly complex fluid deformation occurs due to instabilities, which is challenging to study numerically. SPRAY is particle-based, mesh-free, and Lagrangian, which addresses numerical issues that posed difficulties to existing methods. Its SPH formulations for RHD governing equations are tailored toward accurate and reliable simulations of laser-target irradiation phenomena, and are solved via a time-dependent, flux-limited diffusion method. A new laser energy coupling module, which is based on the Wentzel-Kramers-Brillouin (WKB) approximation, is implemented with a totally mesh-free ray-tracing scheme that is applicable for arbitrary geometry and dimensions. The accuracy and reliability of the code are demonstrated with a series of benchmark problems. To the authors' knowledge, this is the first attempt to employ SPH method for simulations of laser-plasma interactions in high energy density physics research. Possible expansions to the code, such as laser beam-beam interaction modeling and more sophisticated multi-group radiation transport are left for future development.