Ceramic Gas Turbine Technology Development

Abstract

AlliedSignal Engines is addressing critical concerns slowing the commercialization of structural ceramics in gas turbine engines. These issues include ceramic component reliability, commitment of ceramic suppliers to support production needs, and refinement of ceramic design technologies. The stated goals of the current program are to develop and demonstrate structural ceramic technology that has the potential for extended operation in a gas turbine environment by incorporation in an auxiliary power unit (APU) to support automotive gas turbine development. AlliedSignal Engines changed the ATTAP ceramic engine test bed from the AGT101 automotive engine to the 331-200[CT] APU. The 331-200[CT] first-stage turbine nozzle segments and blades were redesigned using ceramic materials, employing design methods developed during the earlier DOE/NASA-funded Advanced Gas Turbine (AGT) and the ATTAP programs. The ceramic design technologies under development in the present program include design methods for improved resistance to impact and contact damage, assessment of the effects of oxidation and corrosion on ceramic component life, and assessment of the effectiveness of nondestructive evaluation (NDE) and proof testing methods to reliably identify ceramic parts having critical flaws. AlliedSignal made progress in these activities during 1993 ATTAP efforts. Ceramic parts for the 331-200[CT] engine have been fabricated and evaluated in component tests, to verify the design characteristics and assure structural integrity prior to full-up engine testing. Engine testing is currently under way. The work summarized in this paper was funded by the U.S. Dept. of Energy (DOE) Office of Transportation Technologies and administered by NASA-Lewis Research Center, under Contract No. DEN3-335.