Versatile Thermal Insulation for Cryogenic Upper Stages



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46th International Conference on Environmental Systems


Within ESAs future launcher preparatory program RUAG Space has developed a Versatile Thermal Insulation (VTI) system for cryogenic launcher upper-stages. The pneumatically deployable VTI system is self-sustained and mounted via interchangeable segments on the payload interface adapter. At this location the system is protected from environments on the launch pad and aerothermal loads during lift-off. On the interface adapter the VTI is independent from the upper stage, which in turn does not need to be modified for the insulation system. As the insulating VTI segments are adaptable in size the system can be designed to any cryogenic upper stage configuration. VTI is thus a viable upgrade kit for existing- and future launchers. In orbit VTI segments deploy on command through pressurization in a sequence that concludes in an insulating skirt covering the cryogenic stage. The entire deployment process is solely controlled by pressure and built-in retainers made of hook/loop fasteners. Apart from the hold-down and release assembly no additional mechanism is needed for deployment. This approach reduces system complexity and leads to a mass below 80kg for a 75m2 covering VTI system. The deployment process has been successfully verified with a full scale, 1.5 meter by 5 meter, demonstrator model of one VTI segment. It was demonstrated that deployment is reliable and reproducible in real size and that stowing in rolled form is compatible with launch loads. Thermal analyses have shown that on a generic 4.4m upper stage the developed VTI system reduces the heat input into the liquid hydrogen tank by more than 90% resulting in a strongly reduced fuel boil-off rate.


RUAG Space GmbH
European Space Agency ESA
European Space Agency - ESA
RUAG Schweiz AG
ICES106: Thermal Control for Space Launch Vehicles, Propulsion, and Nuclear Power Systems
Vienna, Austria
M. Moser, RUAG Space GmbH, Austria
W. Hoidn, RUAG Space GmbH, Austria
P. Delouard, RUAG Space AG, Switzerland
A. Tvaruzka, European Space Agency ESA, The Netherlands
M. Loche, European Space Agency ESA, The Netherlands
U. Lafont, European Space Agency ESA, The Netherlands
The 46th International Conference on Environmental Systems was held in Vienna, Austria, USA on 10 July 2016 through 14 July 2016.


Cryogenic upper stage, boil-off, Deployable, Thermal Insulation