Conceptual Design and Three-dimensional Analysis for Commercial-Scale Faraday-Type MHD Generator

*** † ‡ A new design of commercial-scale Faraday-type MHD generator has been done for a coal-fired CO2 recovery power system, and detailed three-dimensional analyses have been carried out. The following results have been obtained. (1) The new design results in 24.2% of enthalpy extraction, leading to about 55% (on the basis of Higher Heat Value, HHV) of the overall system efficiency including the electric power required for CO2 liquefaction (recovery). (2) The generator performance obtained by the three-dimensional analysis agrees generally with the design value, although some discrepancy of the flow field appears. (3) The overshoot of the boundary layer appears near the insulating wall, and the vortex flow is produced on the plane perpendicular to the main flow direction. These are induced by the strong three-dimensional MHD interactions. (4) An analysis of short circuit of loading has been carried out, showing an intensive current concentration, suggesting a requirement of some protection device.