Optimization of the propulsion cycles for advanced shuttles. I - Propulsion mass model methodology

During the past year NASA and DLR computer codes were combined in order to analyze and optimize advanced rocket launcher systems. Previous optimization results led to relatively low chamber pressures and nozzle area ratios for the different cycles. Additional effort has been made to improve the verification of propulsive parameters such as chamber pressure, nozzle extension, kind of cycle, tripropellant systems, variable mixture ratio rocket motors, new technology effects, etc. The emphasis of this paper is to describe the methodology of the improved propulsion mass model.