Progress in the testing of coal-fired MHO generator ceramic channels

Abstract

AbstractExperimental results of recent ceramic channel tests performed under open cycle MHD conditions in the Electro technical Laboratory (ETL) COM-Fired Test Facility (ECFTF) are reported. The ceramic insulators and electrodes show good compatibility in the MHD channel environment.The performance of sialon (Si3N4-AI2O3-AIN) +oxide (Cr2O3), MgO +metal (NiCr alloy and pure Ni) composite, and SiC insulators and Cr2O3 and SiC electrodes are reported. Ceramic channel walls suitable for liquid slagging conditions and the design of a cooling system, including the ceramics to metal bonding technology, have been developed.Results of the splash experiments under high heat flux conditions indicate that the MgO with MgO-Ni alloy composite and copper nickel laminated relaxation layers were effective at surface temperatures around 1200°C and with a heat flux of about 100 W/cm2 Up to around 150 W/cm2, the insulators were damaged by ceramic to ceramic-metal composite interface separation caused by disproportionate ther...