A5031392582- Laser-induced spectroscopy and plasma
- Atomic and Molecular Physics
- Plasma Diagnostics and Applications
- Gas Dynamics and Kinetic Theory
- Analytical chemistry methods development
- Ion-surface interactions and analysis
- Advanced Chemical Physics Studies
- Metal and Thin Film Mechanics
- Computational Fluid Dynamics and Aerodynamics
- Laser Design and Applications
- Plasma and Flow Control in Aerodynamics
- Plasma Applications and Diagnostics
- Spectroscopy and Laser Applications
- Ionosphere and magnetosphere dynamics
- Mass Spectrometry Techniques and Applications
- Diamond and Carbon-based Materials Research
- Vacuum and Plasma Arcs
- Astro and Planetary Science
- Laser-Ablation Synthesis of Nanoparticles
- Catalytic Processes in Materials Science
- Combustion and flame dynamics
- Dust and Plasma Wave Phenomena
- Fusion materials and technologies
- Magnetic confinement fusion research
- Fluid Dynamics and Turbulent Flows
Complexe de Recherche Interprofessionnel en Aérothermochimie
2015-2024
Centre National de la Recherche Scientifique
2015-2024
Université de Rouen Normandie
2012-2024
Normandie Université
2014-2023
Institut National des Sciences Appliquées Rouen Normandie
2014-2019
National Council for Scientific Research
2011
A nonlinear time-dependent collisional-radiative model for recombining argon is presented. Reactions involving Ar(2)+ are taken into account and their influence discussed. It shown that may increase the time to reach quasi-steady-state by a factor of 100. The calculation recombination rate coefficient at An analytical expression derived compared with existing literature values. importance illustrated comparisons excited levels population densities distribution measured in fast moving plasma...
A nonlinear time-dependent two-temperature collisional-radiative model for air plasma has been developed pressures between 1kPa and atmospheric pressure to be applied the flow conditions of space vehicle re-entry into Earth’s atmosphere. The consists 13 species: N2, O2, N, O, NO, N2+, O2+, N+, O+, NO+, O2−, O− in their ground state major electronic excited states electrons. Many elementary processes are considered given temperatures involved (up 10 000K). Time scales reach final...
An accurate investigation of the behavior electronically excited states atoms and molecules in postshock relaxation zone a trajectory point Flight Investigation ReentryEnvironment 2 (FIRE II) flight experiment is carried out bymeans one-dimensional flow solver coupled to collisional-radiativemodel. Themodel accounts for thermal nonequilibrium between translational energy mode gas vibrational individualmolecules. Furthermore, electronic andmolecules are treated as separate species, allowing...
Abstract As part of the development proven diagnostics allowing characterization ITER’s PFUs (Plasma Facing Units) without dismantling, LIBS (Laser-Induced Breakdown Spectroscopy) is a serious candidate for determining multi-elemental composition. In this article, we report measurement campaign carried out within WEST tokamak using an original device based on following technological choices. (1) The laser source and spectrometer are placed outside tokamak. (2) pulses conveyed by optical...
The effects of non-equilibrium in a quasi-one-dimensional nozzle flow are investigated by means collisional-radiative model. gas undergoing the expansion is an air plasma and consists atoms, molecules, free electrons. In present analysis, electronic excited states atomic molecular species treated as separate pseudo-species. Rotational vibrational energy modes assumed to be populated according Boltzmann distributions. coupling between radiation dynamics accounted for, simplified manner, using...
The most relevant way to predict the excited state number density in a nonequilibrium plasma is elaborate collisional–radiative (CR) model taking into account of collisional and radiative elementary processes. Three examples such an elaboration are given this paper case various flows related planetary atmospheric entries. theoretical determination nitrogen atom ionization or recombination global rate coefficients under electron impact addressed first. coefficient can be implemented...
The flow field modeling of planetary entry plasmas, laser-induced inductively coupled arcjets, etc., requires to use Navier-Stokes codes. kinetic mechanisms implemented in these codes involve global (effective) rate coefficients. These coefficients result from the excited states coupling during a quasi-steady state. In order obtain over wide electron temperature (Te) range for ionization and recombination carbon, nitrogen, oxygen, argon, behavior their is investigated using zero-dimensional...
Evaluating the mole fraction of hydrogen isotopes in a solid is difficult task. Few methods allow it to be achieved. LIBS laser method based on electronic excitation elements and spontaneous emission characteristic optical lines. On sample containing isotopes, α-type lines can estimate their total fraction. In addition, discriminating because separate contributions isotopes. This paper reports implementation this thin film-type samples tritium. They consist nanometric layers palladium...
Extensive calculations of the rate coefficients for dissociative recombination (DR), elastic collisions, inelastic collisions (ICs) and superelastic NO+ ions on initial vibrational levels, , with electrons energy between 10−5 10 eV have been performed, a method based multichannel quantum defect theory. Comparisons DR plasma experimental results give good agreement, confirming that vibrationally excited recombine more slowly than those in ground state. Also, our state IC are very similar to...
The two-temperature collisional-radiative model CoRaM-AIR, working over a wide range for pressure and temperatures, has been developed the flow conditions around space vehicle entering Earth's atmosphere. species N2, O2, NO, N, O, Ar, N2+, O2+, NO+, N+, O+, Ar+, free electrons are taken into account. is vibrationally specific on ground electronic state of electronically all species, with total 169 vibrational states 829 states, respectively. A set elementary processes considered under...
Nonequilibrium plasma, produced by the propagation of a shock wave in tube or behind front detached from body entering planetary atmosphere, requires development state-to-state models. The collisional-radiative model for has been elaborated on this framework pure nitrogen flows. Its elaboration is reported paper. includes , N, and free electrons thermochemical nonequilibrium. vibrationally electronically specific insofar as vibrational states electronic ground state excited ; are...
Cross sections and thermal rate coefficients are computed for electron-impact dissociative recombination vibrational excitation/de-excitation of the N2+ molecular ion in its lowest six levels, collision energies/temperatures up to 2.3 eV/5000 K.
The latest molecular data—potential energy curves and Rydberg/valence interactions—characterizing the super-excited electronic states of CO are reviewed, in order to provide inputs for study their fragmentation dynamics. Starting from this input, main paths mechanisms CO+ dissociative recombination analyzed; its cross sections computed using a method based on multichannel quantum defect theory. Convoluted sections, giving both isotropic anisotropic Maxwellian rate coefficients, compared with...
Multichannel quantum defect theory is applied in the treatment of dissociative recombination and vibrational excitation processes for BeD$^+$ ion twenty four levels its ground electronic state ($\textrm{X}\,{^{1}\Sigma^{+}},v_{i}^{+}=0\ldots 23$). Three symmetries BeD$^{**}$ states (\ensuremath{^{2}\Pi}, \ensuremath{^{2}\Sigma^{+}}, \ensuremath{^{2}\Delta}), are considered calculation cross sections corresponding rate coefficients. The incident electron energy range $10^{-5}$--2.7 eV...
The latest molecular data -potential energy curves and Rydberg-valence interactions -characterising the super-excited electronic states of BF are reviewed in order to provide input for study their fragmentation dynamics.Starting from this input, main paths mechanisms + dissociative recombination vibrational excitation analysed.Their cross sections computed first time using a method based on multichannel quantum defect theory (MQDT), Maxwellian rate-coefficients calculated displayed...
First results are presented in relation with experimental and theoretical studies performed at the CORIA laboratory general framework of determination chemical analysis Tokamak plasma facing materials by laser-induced breakdown spectroscopy (LIBS) picosecond regime. Experiments on W a specific chamber. This chamber is equipped UV-visible-near IR spectroscopic device. Boltzmann plots derived for typical laser characteristics. We show that initial excitation temperature close to 12 000 K...
To predict the nonequilibrium flows around a hypersonic vehicle entering Martian atmosphere, two-temperature collisional-radiative model “CoRaM-MARS” has been developed. The species CO2, CO, C2, CN, N2, NO, O2, C, N, O, Ar, CO+, C2+, CN+, N2+, NO+, O2+, C+, N+, O+, Ar+, and free electrons are taken into account. can therefore be used for conditions belonging to wide ranges of temperatures pressures. is vibrationally specific on ground electronic state O2 electronically all species, with...
We study the stagnation point boundary layer of high enthalpy subsonic flows obtained in inductively coupled plasma torches, aiming at determining catalytic properties materials for reentry applications. Simple recombination processes are often considered with same probability wall. In this work, a phenomenological model has been used to describe more accurately gas-surface interaction. This shows that strongly dependent on wall temperature, concentration different species close wall, and...
The radial profiles of metastable and ground state atomic number densities at numerous sections a supersonic nitrogen plasma jet have been derived from UV absorption emission spectroscopy. An original method that provides the density ratio intensities 119.955, 120.022 120.071 nm resonance lines has developed. Along axis direction, similarly to N N2+ excited states, decreases more steeply centre than its border. At exit source, our results throw doubt upon dissociation rate usually considered...