Investigations of thermally resistant structures for future aerospace vehicles.

Abstract

The feasibility of future aerospace vehicles depends on advanced structural concepts to achieve sufficient mechanical load capacity combined with high resistance against strong heat fluxes and large temperature gradients. Experiments on metallic structures such as a thermal protection system, hot load carrying panels, and a wing box were carried out in DLR test facilities within the temperature range up to 1000 grad C. As an alternative to metals, fiber-reinforced polymers and glasses for applications under moderate and/or cryogenic temperatures and under steep temperature gradients were also investigated. Complementary to this technological and experimental approach, corresponding numerical procedures have been established. Analytical and numerical methods deriving thermal conductivities and thermal elongations of laminates from the fiber and matrix properties were validated. Special Finite Elements based on thermal lamination theories have been developed to analyse efficiently the temperature field of multi-directional laminates.