세미나

The desire to maintain thermal loads acting on re-entry vehicles within acceptable limits drives numerous activities pertaining to research and
development of thermal-protection materials. Metallic thermal-protection materials with low mass densities and life-cycle costs as well as greater
strength to withstand thermal loads have been widely employed in the design and manufacture of re-entry as well as reusable launch vehicles. It
is well known that exothermic catalytic recombination effects govern the magnitude of surface heat transfer via diffusion, which may be greater
compared to conductive heat transfer. It has previously been demonstrated that recombination phenomena account for up to 30% of the total heat
transfer during reentry into Earth’s atmosphere.

Thermal-protection materials employed in the base heat shield of re-entry vehicles are subjected to significantly different surface heat-transfer
phenomena depending upon their catalytic efficiency. Therefore, to facilitate accurate prediction of thermal loads during re-entry, it is important to
accurately determine the catalytic efficiency of materials employed in vehicle construction.

The purpose of this seminar is to share the recent experimental results regarding the assessment of the oxygen/nitrogen catalytic efficiency of
metals and metal-oxides through use of a shock tube under controlled test conditions and specimen surfaces such that sources of errors in the
measurements are eliminated or at least minimized.