Diffusion effects on the determination of surface catalysis in Inductively Coupled Plasma facility
| Autor: | Alan Viladegut, Umran Duzel, Olivier Chazot |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
Coupling
Work (thermodynamics) Chemistry General Physics and Astronomy 02 engineering and technology Plasma 01 natural sciences 010305 fluids & plasmas Calorimeter Boundary layer 020303 mechanical engineering & transports 0203 mechanical engineering Heat flux 0103 physical sciences Physical and Theoretical Chemistry Inductively coupled plasma Diffusion (business) Atomic physics |
| Zdroj: | Chemical Physics. :88-97 |
| ISSN: | 0301-0104 |
| DOI: | 10.1016/j.chemphys.2017.02.002 |
| Popis: | Atomic recombination is an important process to consider when computing the heat flux transferred to the wall of a re-entry vehicle. Two chemical processes are influencing the species diffusion in the boundary layer surrounding a re-usable Thermal Protection System: gas phase reactions and catalytic recombination at the surface. The coupling between them is not normally taken into account when determining the catalytic recombination coefficient ( γ ) in plasma facilities. This work aims to provide evidence of such coupling based on both a theoretical analysis and an experimental campaign in the VKI-Plasmatron facility. Recombination coefficient measurements at off-stagnation point configuration on a linear copper calorimeter are provided. An evolution from a high-catalytic to a low-catalytic condition due to the boundary layer growth along the probe is observed. This result is consistent with a parametric analysis carried out using the in-house non-equilibrium boundary layer solver, which shows how the experimentally determined catalysis could be influenced by the amount of gas-phase recombination inside the boundary layer. |
| Databáze: | OpenAIRE |
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