Enhancement of Endothermic Capacity and Combustion Efficiency of Fuels for Hypersonic Propulsion

ABSTRACT: The Air Force identified a need to enhance the capabilities of scramjet-powered hypersonic systems through the development of technologies such as advanced endothermic fuels, fuel additives, catalysts or fuel cooling concepts for high-speed propulsion systems. Physical Sciences Inc. (PSI), in collaboration with the United Technologies Research Center (UTRC), proposes to develop fuel modification technologies that will enhance the endothermic capacity and combustion efficiency of hydrocarbon fuels for mid-scale scramjets. These fuels are required to maintain thermal balance for the flight vehicle using only the onboard fuel as heat sink without sacrificing integrated system performance. Our proposed high density, miscible liquids as fuel additives will enhance the performance of hypersonic propulsion systems by: 1) increasing endothermic heat sink of the fuel, 2) suppressing coking in coolant passages during endothermic cracking of the fuel, and 3) forming a cracking product distribution that, entering the scramjet combustor results in fast ignition and complete combustion. On a potential Phase II, we will demonstrate the feasibility of this advanced fuel concept to increase the capabilities of scramjet systems. We will perform detailed numerical modeling and subscale testing of our proposed approach and assess the impact of this enhancing technology to identify pathways for various applications. BENEFIT: Full development of our technology will result in the production of advanced fuel products that will have applications in high-speed military systems, as well as in future high-speed commercial applications.