Finite Rate Surface Catalysis Modelling of PM1000 and SiC Employing the DLR CFD Solver TAU

Abstract

Within the frame of the ESA research project 'Development of an Innovative Validation Strategy of Gas-Surface Interaction Modelling for Re-Entry Applications' (GSI) the pressure dependency of surface catalysed Oxygen and Nitrogen recombination on PM1000 and SiC at temperatures relevant for the re-entry of a space vehicle has been investigated for the first time. The measurements of Massuti-Ballester show, that oxygen recombination significantly depends on pressure. At 1400 K the oxygen recombination probability on C/C-SiC decreases with increasing oxygen partial pressure. Since the Eley-Rideal recombination mechanism is expected to be pressure independent at this temperature, the finding supports the modelling that a high temperature Langmuir-Hinshelwoood mechanism is responsible for the pressure dependency. A similar dependency was observed for PM1000 at 1500 K. The new data allows for an improved modelling of the oxygen recombination probability on SiC and PM1000.