Technology Investigation for High Area Ratio Nozzle Concepts

Kurzfassung

Bell-type nozzle concepts are state -of-the-art technology for expanding gases towards high exhaust velocities. Alternative nozzle concepts have been investigated, although none of them has achieved full-scale flight hardware status. These concepts include altitude adaptive concepts for first stage application, and concepts with reduced length for upper stage application. Both applications have the common requirement that for the thrust chamber design, accurate prediction models for the wall pressure evolution, the wall heat transfer, and the side-load characteristic are of importance. To enhance corresponding design models, the need of well tailored subscale tests at elevated thrust levels has been identified and expressed by the three partners EADS Space Transportation (former Astrium, Space Infrastructure), DLR Lampoldshausen, and Volvo Aero Corporation. Consequently, a joint programme has been formulated, the Calorimeter Nozzle Programme . Within the frame of this Calorimeter Nozzle Programme, three different thrust chamber configurations including actively cooled and film-cooled nozzle extensions are build, tested, and analyzed. Tests are performed with hydrogen-oxygen propellant combination at mixture ratios between 5 and 7.5, and at elevated combustion chamber pressures up to 130 bars.