Refined mean field model of heat and momentum transfer in magnetoconvection

TL;DR

This paper revisits and refines a theoretical model for heat and momentum transfer in magnetoconvection, extending it to all Hartmann numbers and comparing it with experimental data, highlighting successes and limitations.

Contribution

The authors simplify and extend an existing magnetoconvection model to cover the full Hartmann number range, aligning it with recent experimental and numerical findings.

Findings

Heat transport is well described by the revised model.

Reynolds number predictions are less accurate, indicating model limitations.

Model aligns with Grossmann-Lohse theory in zero magnetic field limit.

Abstract

In this article, the theoretical model on heat and momentum transfer for Rayleigh-B\'enard convection in a vertical magnetic field by Z\"urner et al. (Phys. Rev. E 94, 043108 (2016)) is revisited. Using new data from recent experimental and numerical studies the model is simplified and extended to the full range of Hartmann numbers, reproducing the results of the Grossmann-Lohse theory in the limit of vanishing magnetic fields. The revised model is compared to experimental results in liquid metal magnetoconvection and shows that the heat transport is described satisfactorily. The momentum transport, represented by the Reynolds number, agrees less well which reveals some shortcomings in the theoretical treatment of magnetoconvection.