PERFORMANCE OPTIMIZATION OF TURBORAMJET ENGINES PROPELLING A 2-STAGE SPACE TRANSPORTATION SYSTEM

A multistep prediction and design procedure is examined that couples t he steps of engine analysis and vehicle performance optimization for t he requirements of a typical space transportation system. The methodol ogy of turboramjet engine analysis employs an energy-state approximati on to enable a preliminary optimization of the engine operation for a fuel efficient acceleration. The turboramjet characteristics predicted are then used in a mission performance optimization algorithm in orde r to verify the mission assumptions used for the engine analysis, to d etermine the engine and vehicle controls for minimum fuel consumption, and to assess the overall mission performance. The results demonstrat e both the validity of key assumptions and the capabilities of the eng ine design tool developed.