Systems Analysis on Hypersonic Airplanes using Pre- Cooled Turbojet Engine

Systems analysis and evaluation of Mach 5 class hypersonic airplanesis performed. The airplanecan fly across the Pacific Ocean in 2 hours. A multi-disciplinary optimization program with aerodynamic, thermal structure, propulsion and trajectory is used to define baseline shape. Pre-cooled turbojetengine is assumed as the propulsion system for the hypersonic airplane. The engine can be operated from takeoffto Mach 5, continuously. This engine has adopted pre-cooling cycle using cryogenic liquid hydrogen. The high temperature inlet air at the hypersonic flightwill be cooled by liquid hydrogenfor fuel. Surface flow of the airplaneat hypersonic speedand low speed are evaluated using results of CFD analyses. The control characteristics with control wings and variation of aerodynamic characteristics by adding strakesare obtained by a low speed wind tunnel experiment. The heat flux distribution on the surface of the airframeat hypersonic cruise condition is evaluated by using the results of CFD analyses. The characteristics of heat shieldmaterials for the surface of the fuselageat downstream of the exhaust gas is evaluated by an elemental experiment.