Thermal instability in natural convection flow over a boundary layer subject to external electrical and magnetic fields

摘要

This paper presents a numerical study of external electrical and magnetic effects on the formation of longitudinal vortices in natural convection flow over a heated horizontal plate. The criterion on the position marking on the onset of longitudinal vortices is defined in the present paper. The onset position characterized by the Grashof number depends on the Prandtl number, the wave number, the electric field parameter, and the magnetic field parameter. The flow is found more stable as the value of the magnetic field parameter increases. Moreover, the stabilizing effect is also found on the flow when the positive electric field parameter Ec is applied. The results of the present numerical prediction show reasonable agreement with the experimental data with zero magnetic field and electric field parameters in literature.