Adiabatic efficiency of supersonic Faraday MHD generator

Objectives of the present experimental study are to investigate adiabatic efficiencies of a supersonic Faraday MHD (magnetohydrodynamics) generator with cesium-seeded argon and at the same time to achieve a high enthalpy extraction. MHD power generation experiments were carried out with a shock tube facility. The MHD channel has 35 pairs of electrodes and the width between its insulator walls is expanded along the flow direction. Total pressures were measured at the exit of the MHD channel and total pressure losses were evaluated. Furthermore, the adiabatic efficiency was measured for the first time in the present experiments in which an enthalpy extraction ratio of about 10% was achieved. Comparison of these results with those obtained using a disk-type generator indicates that a Faraday generator has higher adiabatic efficiencies at the same enthalpy extraction ratio. The influence of voltage drops on loading parameters and electrical efficiencies is also discussed.