Optimization analysis of an alternate magnetohydrodynamic generator

The production of electric power through the oscillatory motion of an electrically conducting fluid in a continuous electrode Faraday generator is considered. The performance of this alternate magnetohydrodynamic (MHD) generator is analyzed using the conventional isotropic electrical efficiency and an overall second law efficiency, based on the global entropy generation rate. The velocity, electric current density and temperature fields for the oscillatory Hartmann flow are calculated in order to assess, in terms of the entropy generation rate, the dissipative phenomena caused by fluid friction, Joule heating and heat transfer in the MHD generator. The overall second law efficiency is used to determine optimum operation conditions that minimize process irreversibilities. (C) 2002 Elsevier Science Ltd. All rights reserved.