| Abstract: | The adiabatic efficiency of a supersonic Faraday MHD (magnetohydrodynamic) generator and its relation to Joule dissipation in the MHD channel were studied in a shock tube experiment. An adiabatic efficiency of 39.7% was obtained at enthalpy extraction of 8.3%. A dissipation process, which reduces the adiabatic efficiency, is examined by evaluating loading parameters and entropy production caused by Joule dissipation. At low load resistance, large Faraday currents in the channel upstream cause extremely large Joule dissipation in both the main flow and the region near the electrodes. It is confirmed experimentally that a high loading parameter yields a high adiabatic efficiency because Joule dissipation is small throughout the MHD channel. © 1999 Scripta Technica, Electr Eng Jpn, 128(4): 47–54, 1999 |
