Cryogenic Launcher Stage Optimization Toolbox

This paper presents an overview of a toolbox that has been developed and validated to aid the development process of future space-launch vehicles. The primary focus lays on structure, geometry, and thermal protection optimization in the early design phase of a cryogenic launcher stage. It is thereby irrelevant whether the envisaged stage operates first, in between, or last during the ascent mission. Even coasting phases (e.g., necessary for transfers into geostationary Earth orbit) may be evaluated from a thermodynamic point of view. Parts of this toolbox have previously been described and verified elsewhere in detail. The presented work connects the different fields, explains the working principle in detail, and demonstrates the capabilities of the toolbox by application to the Ariane 6 upper stage. Furthermore, a parameter study has been conducted to resolve the system response and analyze prime dependencies.