Heat transport in magnetohydrodynamic duct flow regimes with conducting and insulating walls

Abstract

The flow of a liquid metal (LM) in a rectangular duct segment, subject to a uniform transverse magnetic field and uniform heating at the side walls is explored in an ample parameter space using Direct Numerical Simulation (DNS). We modify electrical wall conductivity, (either highly conducting or perfectly insulating) and investigate the effects of the buoyancy force, both in horizontally and vertically orientated ducts. In the latter case, it may be directed either with the flow or against the flow, creating backflow regions. In this parameter space and with the presence of vortex promoters at the inlet of the duct we identify $4$ types of flow. We calculate the Nusselt number $Nu(t)$ for each of them and study the statistical properties to compare their heat transfer capabilities in future fusion reactor blankets.