A Novel OpenFOAM Library for Magneto-Hydrodynamics Studies in the Nuclear Fusion Field

Abstract

The intricate interplay between externally imposed magnetic fields and the dynamic behaviour of conducting fluids constitutes a challenging magneto-hydrodynamic (MHD) multi-physics problem of significant importance within the nuclear field. Studying such phenomena is crucial for comprehending and optimising processes inherent to this field, encompassing scenarios like magnetic confinement fusion reactors. The current open-source OpenFOAM solver, albeit validated, has limited modelling capabilities as it is suited only for incompressible, isothermal, and laminar flows; thus, there is interest in developing a complete MHD library that can tackle fusion-relevant conditions, involving, for example, the MHD flow in liquid metal or molten salts blankets and the confinement of the hot plasma. This work presents the development and verification of magnetoHDFoam, a new OpenFOAM computational library designed for simulating the complex fluid dynamics of MHD flows, with a particular emphasis on practical applications within the domain of the nuclear field. Compared to the existing OpenFOAM library, the presented solver has been designed for transient simulations of compressible fluids, both for laminar and turbulent regime with (eventually) temperature and density variations. For verification, the new library is tested against well-established benchmark tests and analytical cases (Hartmann flow, Shercliff flow, Hunt flow and thermal Shercliff flow) representing MHD phenomena within fusion reactors, focusing on conductive fluids under externally imposed magnetic fields. The library exhibits good agreement with the expected results, confirming its capability to reproduce the effects of magnetic fields on fluid flow regimes. As such, it represents a useful computational tool for the in-depth study of MHD phenomena in the context of nuclear fusion research, offering significant insights into the behaviour of conducting fluids in the presence of magnetic fields.