| The analytical design of a hydrogen fueled, dual-cycle engine having either an annular "wraparound" turboramjet or side-by-side turbofan-ramjet has been conducted. The typical flight profile was assumed with altitude ranging from sea level to 90,000 ft and Mach number from 0 to 5. The overall performances evaluated for both engines are presented in the form of the engine thrust, drag and thrust specific fuel consumption. The corresponding weights and lengths of the engines are also determined.The side-by-side turbofan-ramjet, which is lighter and shorter than the wraparound turboramjet, emerges as an optimum engine configuration. It yields considerably higher overall performance over the entire prescribed flight profile. However, this optimum design requires a side-by-side combustion chamber for ramjet and turbofan afterburner with a variable position wall between the two chambers. The optimum operating mode of the side-by-side turbofan-ramjet is then defined. |
