Constant static-temperature heating for hydrogen fueled scramjet engine

Temperature limits of composite material combustor significantly restricts the hydrogen-fueled scramjet engine performance in a wide range of Mach number flight. In order to solve this problem and conserve fuel, constant static-temperature heating has been newly proposed, which means that the static temperature keeps constant during combustion process of the engine. A thermodynamic cycle including constant static-temperature heating and a compound cycle model are developed corresponding to variable and constant inlet pressure ratios, respectively. Thermodynamic cycle analysis is carried out to evaluate the performance of a scramjet engine at different flight conditions and fuel equivalence ratios. Compared with traditional scramjet cycle, it finds that the two kinds of thermodynamic cycles with constant static-temperature heating can significantly improve the efficiency of the engine and provide greater thrust without over-temperature of combustor. Moreover, to maintain the constant static temperature heating in the scramjet, the area expansion requirements of combustor is also presented via some equations.