par Turchi, Alessandro;Helber, Bernd;Munafò, Alessandro;Magin, Thierry 
Référence 11th AIAA/ASME Joint Thermophysics and Heat Transfer Conference(11: 2014-06-16), American Institute of Aeronautics and Astronautics Inc
Publication Publié, 2014
Référence 11th AIAA/ASME Joint Thermophysics and Heat Transfer Conference(11: 2014-06-16), American Institute of Aeronautics and Astronautics Inc
Publication Publié, 2014
Publication dans des actes
| Résumé : | Ablative materials are extensively used in several aerospace applications. Their employ as heat shield for re-entry capsules enables to survive re-entry conditions that would be otherwise unfeasible. The coupled experimental-numerical work is fundamental to grow the understanding of their behavior in operative conditions. This work deals with the development and testing of an ablation model able to reproduce the stagnation-point gas-surface interaction over non-charring carbon-based ablative materials. Numerical tools, specifically developed at the von Karman Institute for Fluid Dynamics for re-entry application studies, are used together in the analysis to obtain relevant quantities as the stagnation-point surface mass blowing rate and temperature. Data from the experiments performed in the von Karman Institute Plasmatron in both air and nitrogen environment are used to compare with the numerical results and to tailor the ablation model. Test results in nitrogen environment prove that active surface nitridation takes place, and a proper nitridation reaction probability is extracted from the tests using the developed model with a reverse approach. Comparisons with the measured surface temperatures suggest that additional surface phenomena can occur in the low cold-wall heat flux tests. Surface nitrogen recombination, identified as one of these possible mechanisms, is analyzed. |
