Effects of Hartmann number and conductance ratio on the flow imbalance in merging ducts with locally different electric conductivities

Abstract

In this study, examined are three-dimensional Liquid metal (LM) Magnetohydrodynamic (MHD) flow and convective heat transfer in merging ducts with locally different electric conductivities, having two inlets and one outlet, under a uniform magnetic field. Computational fluid dynamics simulations are performed to predict the behavior of the MHD flows in the ducts. Though numerous analytic, experimental and numerical studies on LM MHD duct flows were performed, detailed flow characteristics of a LM MHD flow in a merging duct with locally different electric conductivities have rarely been studied. In the present study, the interdependency of the current, fluid velocity, pressure, electric potential is examined in order to describe the electromagnetic characteristics of the liquid-metal flows in merging ducts. Here, cases with various arrangements of the electric conductivity in two inflow channel walls are considered for different Hartmann numbers, yielding different distributions of the fluid velocity in different cases, which leads to the imbalance of mass flow rate in the inflow channels, allowing differential cooling in a liquid metal cooling system of a fusion reactor.