Wavy Taylor Vortex Effect on Power Generation Characteristics of Co-axial Magnetohydrodynamic Energy Conversion Device

Three-dimensional numerical analysis is conducted to clarify the effect of wavy Taylor vortices on the power generation characteristics of a co-axial magnetohydrodynamic energy conversion device. The numerical results show that time-periodic oscillations in the input and output powers occur when the load factor, which is defined as the ratio of the load voltage to the induced electromotive force, is below a threshold. These are caused by the modulation of the wavy Taylor vortices induced inside the device. Additionally, the oscillation amplitude of the output power is considerably small even when the oscillation amplitude of the input power is maximum. The effects of Taylor vortices and Lorentz force on the input power are also investigated. The dependence of the input power on the load factor is determined by the balance between the contribution from inertial force (convection), which increases with increasing load factor, and the contribution from the Lorentz force, which decreases with increasing load factor.