Pseudo-spectral solver versus grid-based solver: A quantitative accuracy test using GMHD3D and PLUTO4.4

Abstract: We provide a thorough comparison of the GMHD3D code and the PLUTO4.4 code for both two and three-dimensional hydrodynamic and magnetohydrodynamic problems. The open-source finite-volume solver PLUTO4.4 and the in-house developed pseudo-spectral multi-GPU solver GMHD3D both can be used to model the dynamics and turbulent motions of astrophysical plasmas. Although GMHD3D and PLUTO4.4 utilize different implementations, it is found that simulation results for hydrodynamic and magnetohydrodynamic problems, such as the rate of instability growth, 3-dimensional turbulent dynamics, oscillation of kinetic & magnetic energy, and recurrence dynamics, are remarkably similar. However, it is shown that the pseudo spectral solver GMHD3D is significantly more superior than the grid based solver PLUTO4.4 for certain category of physics problems.