Development of an Innovative Validation Strategy of Gas-Surface Interaction Modelling for Re-Entry Applications — TN4210 - Development and validation of numerical models in TAU

Kurzfassung

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 Herdrich and Massuti 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.