Thermal Fluid-Structure Interaction in Different Atmospheres

A generic nosecap model was tested in the arc heated facility L3K. The model was particularly designed to show thermomechanical fluid-structure interaction phenomena when heated by hypersonic high enthalpy flow. In particular, displacement measurements on the model's nose plate showed a very good agreement to coupled simulations of flow and structure. When heated in air flow local temperature maxima were observed that propagate like a wave along the surface. A comparative test campaign on SiC samples in air and nitrogen flow verified that the phenomenon can be explained by heat flux enhancement due to catalytic oxygen recombination at the surface at temperatures between 1200 K and 1500 K