Development of Cryogenic Insulations for Launcher Upper Stages
AIRBUS D&S, Bremen has executed a program for development of cryogenic insulations for application on upper stages for future launchers. Insulations under consideration are those applied inside the hydrogen tank as well as external surfaces of hydrogen and oxygen tanks. Currently a status of TRL 3 has been achieved and the next phase has been commenced heading for TRL 4/5. Until TRL 3 the foam basic material has been developed and down-selected to the most appropriate ones for internal and external applications. The chemical composition and structure as well as the cell morphology have been frozen. Parameters for manufacturing have been investigated on lab scale as well in very detail and have been preliminarily frozen. Comprehensive characterization and qualification has been done for LN2 conditions for physical, mechanical and thermal properties. For the most important properties a first characterization has been performed under LH2 conditions. All the measurements and tests performed so far exhibit excellent and promising results. Now for the next phase (IWTI = ~1 year. ETI = ~2 years) the insulation concepts will be established incorporating such components/aspects as liners, substructure fixation and NDI methods. Detailed characterization/qualification under LN2 and LH2 is intended on sample as well as on building block level. This paper refers to the achievements of the development performed so far and will discuss the development approach for the next maturation phase.
Wolfgang P.P. Fischer, AIRBUS Defence & Space, Germany