Low Cost, High Performance SiC Recuperators

There is a critical need for the development of high temperature, corrosion resistant, low weight, and low cost recuperators to increase the efficiency of advanced gas turbine engines. The temperature requirements dictate the use of ceramic materials, and the material choice is silicon carbide (SiC) as a result of its high thermal shock resistance, high thermal conductivity, excellent corrosion resistance, and low density. However, available SiC commercial materials are very costly and lacking in mechanical performance. This proposal addresses the need for low cost, high performance SiC ceramic materials with the development of two difference SiC materials, i.e. a siliconized SiC fiber reinforced composite and a siliconized SiC monolith with tailorable microstructure. Each offers the potential for much higher toughness combined with complex shape forming capabilities. All materials will be fully characterized, and the optimum materials tested at the Allison Gas Turbine Division of General Motors Corporation. The program will culminate in the development of a preliminary recuperator design (at Allison Gas Turbine) and a cost analysis for the production of recuperator components. The determination of fabrication costs combined with assessment of thermal and mechanical properties will determine the feasibility of using the proposed SiC-based materials in recuperator applications.