An electrodeless AC MHD generator and pump

Summary form only given. An electrodeless magnetohydrodynamics (MHD) generator and pump have been developed whose major advantages are that the electrodeless design avoids electrode arcing and damage and that the AC coupling avoids the high-current, low-voltage DC that has caused power transfer difficulties in the past. The basic concept is to provide an iron core linking a closed current path in the gas or the conducting fluid. The iron increases the effective permeability of the current carrying gas, so that the magnetic flux is trapped for a sufficiently long time to permit AC operation of moderate frequency and size. Both the generator and the pump have been tested successfully in a mercury-fluid model. There has been much interest in this concept for ship propulsion in electrically conducting seawater, as gassing by electrolysis at the electrodes cannot occur