Ultraviolet fixation of molecular contamination: physical model numerical implementation and validation
| Autor: | Delphine Faye, Pascale Guigue, Emilie Vanhove, Jean-François Roussel, Thomas Tondu |
|---|---|
| Přispěvatelé: | ONERA - The French Aerospace Lab [Toulouse], ONERA, Centre National d'Études Spatiales [Toulouse] (CNES) |
| Jazyk: | angličtina |
| Rok vydání: | 2016 |
| Předmět: |
Materials science
Condensation Aerospace Engineering Substrate (chemistry) 02 engineering and technology Contamination 021001 nanoscience & nanotechnology medicine.disease_cause 01 natural sciences Chemical reaction MOLECULAR CONTAMINATION [PHYS.PHYS.PHYS-SPACE-PH]Physics [physics]/Physics [physics]/Space Physics [physics.space-ph] 010309 optics Adsorption 13. Climate action Space and Planetary Science Chemical physics 0103 physical sciences Ultraviolet light medicine Deposition (phase transition) CONTAMINANT REEMISSION 0210 nano-technology Ultraviolet |
| Zdroj: | Journal of Spacecraft and Rockets Journal of Spacecraft and Rockets, American Institute of Aeronautics and Astronautics, 2016, 53 (6), p. 1159-1165. ⟨10.2514/1.A33504⟩ |
| ISSN: | 0022-4650 1533-6794 |
| Popis: | International audience; Physical contamination results from a competition between the deposition of incoming contaminants and their reemission, depending on the surface temperature. However, interaction with ultraviolet light greatly inhibits reemission. Ultraviolet light can lead to chemical reactions, bonding contaminants to the substrate or nearby molecules. This effect can have important consequences in flight. This is especially true for hot surfaces that show no contamination in the absence of ultraviolet light due to their high temperature and can nevertheless be significantly contaminated through photofixation. Previous studies conducted by ONERA–The French Aerospace Lab with Centre National d’Etudes Spatiales allowed identifying the physical mechanisms involved in photofixation and led to a sufficiently simple model to be implemented in engineering software. In this model, the substrate excitation is followed by the reaction of adsorbed contaminants with excited sites. Contaminant chemical photofixation thus results from the competition between their reemission and their reaction with excited sites. This paper presents the implementation of this photofixation model in the numerical tool COMOVA and its validation. It was carried out by modeling test cases, including ground experiments. It demonstrated the qualitative coherence of the photofixation model. The simplest experimental cases with pure contaminants,which have analytical solutions, also quantitatively validated the physical model and its numerical implementation. |
| Databáze: | OpenAIRE |
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