Numerical Prediction of Cavitating MHD Flow of Electrically Conducting Magnetic Fluid in a Converging-Diverging Nozzle

Abstract

The fundamental characteristics of the two-dimensional cavitating MHD flow of an electrically conducting magnetic fluid in a vertical converging-diverging nozzle under a strong nonuniform magnetic field are numerically predicted to realize the further development and high performance of a two-phase liquid-metal MHD power generation system using electrically conducting magnetic fluids. First, the governing equations of the cavitating flow of a mercury-based magnetic fluid based on the unsteady thermal nonequilibrium multifluid model are presented, and several flow characteristics are numerically calculated taking into account the effect of the strong nonuniform magnetic field. Based on the numerical results, the two-dimensional structure of the cavitating flow and cavitation inception phenomena of the mercury-based magnetic fluid through a converging-diverging nozzle are shown in detail. The numerical results demonstrate that effective two-phase magnetic driving force, fluid acceleration, and high power density are obtained by the practical use of the magnetization of the working fluid. Also clarified is the precise control of the cavitating flow of magnetic fluid that is possible by effective use of the magnetic body force that acts on cavitation bubbles.