Laminar magnetohydrodynamics film flows in an open channel of arbitrary electrical conductivity under the influence of a transverse magnetic field are investigated. The effects of the magnetic field, channel conductivity, and channel width on current and velocity distributions are discussed. The present research establishes quantitative scaling law for the magnetic field's impact on the film thickness, utilizing Fourier eigenfunction series and comprehensive physical modeling. The scaling law is validated through direct numerical simulation results and experimental data, which accounts for factors that influence the film thickness, including the Reynolds number (volume flow rate), channel inclined angle, and magnetic field strength. Additionally, the physical mechanism governing the three-dimensional evolution of magnetohydrodynamics films is explored, which finds that a strong magnetic field introduces a Lorentz separation eddy and destabilizes the initially stable, flat film. The present investigations will contribute to the design of flowing liquid metal plasma facing components in tokamak fusion reactors.
This paper investigates the effects of a transverse magnetic field on the flow of liquid metals in an open channel, which is relevant for fusion reactor plasma-facing components. The study establishes a scaling law to predict the impact of the magnetic field on the film thickness, and explores the physical mechanisms behind the three-dimensional evolution of magnetohydrodynamic films.