Ceramic Matrix Composite Materials for Transpiration Cooling

Proposed effort will formulate and demonstrate the methodology for fabricating Porous Ceramic Matrix Composite (PCMC) transpiration plates with controlled levels of porosity, suitable for high-speed/high-temperature missile applications.Process will entail subjecting polymer composites to high-temperature pyrolysisprocess converting it to a porous ceramic matrix and locking the fiber reinforcement in place. Porosity of fabricated plates will be characterized using pycnometer and compared with porous metallic plates with drilled holes constructed for scramjet tests in the CUBRC shock tunnel facility. Thermal and mechanical testing of the PCMC plates will be performed for plates with varied levels of porosity. Preliminary planning for Phase II testing at CUBRC in realistic hypersonic conditions will also be performed, where the CUBRC Combustion Duct model will be used for which detailed experimental and CFD studies have been performed. Preliminary CFD transpiration studies performed earlier have indicated the effectiveness of transpiration in reducing drag in the combustor thus increasing overall performance.