Partner: Damien Vacher

Université d’Auvergne (FR)

Recent publications
1.Kamińska A., Hoffman J., Vacher D., Dudeck M., Szymański Z., Electrical and plasma flow characteristics of a segmented plasmatron operating with mixture of gases, PLASMA SOURCES SCIENCE AND TECHNOLOGY, ISSN: 0963-0252, DOI: 10.1088/0963-0252/24/5/055007, Vol.24, pp.055007-1-13, 2015
Abstract:

The electric characteristics of a segmented plasmatron and the results of optical emission spectroscopy of Ar-air, N2, and N2–CO2 are presented. The main working gas forming the plasma stream was fed near the cathode into the arc region and another additional gas was injected into the plasma stream beyond the arc. It is shown that the gas injected into the plasma stream is drawn to the arc area due to arc spot movement and cyclic arc shrinking and expanding due to the power supply pulsation. It was found that when the anode spot moves upstream, the additional gas is retracted into the arc region, changing the operating conditions of the plasmatron. The retraction mechanism depends on the gas type and is different in argon and molecular plasmas. The results of the plasma emission spectroscopy show differences in the electron excitation and rotational temperatures for the plasmas studied and are used to explain the mechanism of functioning of a segmented plasmatron.

Keywords:

segmented plasmatron, electric properties, optical emission

Affiliations:
Kamińska A.-other affiliation
Hoffman J.-IPPT PAN
Vacher D.-Université d’Auvergne (FR)
Dudeck M.-CNRS (FR)
Szymański Z.-IPPT PAN
2.Kamińska A., Dudeck M., Hoffman J., Szymański Z., Gouy P.A., Vacher D., A plasma jet produced in a segmented plasmatron: modelling and experiment, PHYSICA SCRIPTA, ISSN: 0031-8949, DOI: 10.1088/0031-8949/2014/T161/014072, Vol.T161, pp.014072-1-4, 2014
Abstract:

Nitrogen and argon plasmas with a small admixture of air produced in a segmented plasmatron are studied both experimentally and theoretically. A two-temperature hydrodynamic model is used to simulate the plasma flow inside the plasmatron. The calculated plasma temperature and electron density are in reasonable agreement with the experimental values obtained from emission spectroscopy. The electron temperatures are several thousand kelvins higher than the atom temperatures, showing that the plasmas produced in the segmented plasmatron are in non-equilibrium.

Keywords:

segmented plasmatron, plasma expansion, emission spectroscopy

Affiliations:
Kamińska A.-other affiliation
Dudeck M.-CNRS (FR)
Hoffman J.-IPPT PAN
Szymański Z.-IPPT PAN
Gouy P.A.-Clermont Université (FR)
Vacher D.-Université d’Auvergne (FR)
3.Babou Y., Lequang D., Chazot O., Surzhikov S.T., Dikaljuk A.S., Panarese A., Cicala G., Longo S., Hoffman J., Szymański Z., Kamińska A., Dudeck M., Vacher D., Thermodynamic Characterization of High-Speed and High-Enthalpy Plasma Flows, The Open Plasma Physics Journal, ISSN: 1876-5343, DOI: 10.2174/1876534301407010155, Vol.7, pp.155-172, 2014
Abstract:

This contribution proposes a description of selected experimental activities conducted in aerospace sciences and dedicated to generate experimental data to assess atmospheric entry plasma models. In order to provide comprehensive set of experimental data, high enthalpy shock tube facilities have been developed to generate plasma representative of entry plasma for broad range of trajectory entry conditions. The shock-heated plasma is obtained through adiabatic compression and the resulting post-shock plasma flow exhibits thermodynamic state analogous to actual entry plasma. However, significant insight can be obtained through experiments conducted also with non-equilibrium plasma flows obtained with other methods. The typical methodologies adopted to provide experimental data of interest to enhance entry plasma modeling are sketched for four distinct non-equilibrium plasma kinds produced respectively by four specific ground facilities. The contribution firstly will consider experimental campaigns conducted with a high enthalpy shock tube in order to document in absolute radiance the radiative signature in the UV spectral range of an Earth entry plasma. Then, the investigations of the interaction between a shock wave and an electrical discharge will be described. These investigations were performed to identify the role of the internal degrees of freedom of molecular gases on the propagation of the shock. Also, the contribution covers investigations devoted to the thermodynamic state characterizations by means of spectroscopic diagnostics in the cases of the non-equilibrium plasmas flows generated by plasma wind tunnels. The examination of the Saha-Boltzmann equilibrium is proposed in the case of a subsonic plasma flow. And at last, the characterization methods of air supersonic plasma jet are presented and the 2D distributions of the subsequently measured plasma properties are documented for a straight comparisons with non-equilibrium plasma jet computations.

Keywords:

Abel transform, multi-temperature model optical emission spectroscopy, non-equilibrium plasma, particle in cell - Monte Carlo computation, plasma wind tunnel, Saha balance, shock tube, supersonic plasma

Affiliations:
Babou Y.-von Kármán Institute for Fluid Dynamics (BE)
Lequang D.-von Kármán Institute for Fluid Dynamics (BE)
Chazot O.-von Kármán Institute for Fluid Dynamics (BE)
Surzhikov S.T.-Institute for Problems in Mechanics, Russian Academy of Sciences (RU)
Dikaljuk A.S.-Institute for Problems in Mechanics, Russian Academy of Sciences (RU)
Panarese A.-University of Bari (IT)
Cicala G.-Institute of Inorganic Methodologies and Plasmas (IT)
Longo S.-University of Bari (IT)
Hoffman J.-IPPT PAN
Szymański Z.-IPPT PAN
Kamińska A.-other affiliation
Dudeck M.-CNRS (FR)
Vacher D.-Université d’Auvergne (FR)

Conference papers
1.Kamińska A., Szymański Z., Hoffman J., Vacher D., Menecier S., Dudeck M., Écoulements ionisés dans des plasmatrons pour la simulation des conditions d’entrée en atmosphéres planétaires, Conference on Modelisation : Atomes, Molécules, Plasmas et Systèmes Dynamiques, 2013-05-23/05-24, Bourges (FR), pp.75-86, 2013
Abstract:

Deux plasmatrons a arc non transferes sont utilises pour simuler les proprietes du gaz ionise entourant une sonde d'exploration planetaire. Le plasmatron de I'IEPE (Poznan) d'une puissance maximale de 25 kW fonctionne a pression atmospherique et a pression reduite (p>1 kPa) avec de l'argon, de l'azote et des melanges CO2-N2. La source a arc non transfere du LAEPT (Clermont-Ferrand) d'une puissance applicable maximale de 100 kW fonctionne a pression atmospherique avec de nombreux melanges gazeux dont les melanges N2-O2 et CO2-N2. Une modelisation fluide du plasmatron de I'IEPE est presentee pour de l'argon en tenant compte d'un desequilibre thermique Te-T. Des mesures de temperature par spectroscopie d'emission ont ete realisees dans les jets de plasma obtenus avec les deux plasmatrons. La temperature d'excitation de l'azote atomique et la temperature de vibration de la molecule CN ont ete determinees (IEPE). Les temperatures d'un plasma d'air et d'un plasma de CO2-N2 ont ete determinees a partir de l'emission du cuivre (LAEPT)

Affiliations:
Kamińska A.-other affiliation
Szymański Z.-IPPT PAN
Hoffman J.-IPPT PAN
Vacher D.-Université d’Auvergne (FR)
Menecier S.-Clermont Université (FR)
Dudeck M.-CNRS (FR)

Conference abstracts
1.Kamińska A., Dudeck M., Hoffman J., Szymański Z., Vacher D., Segmented plasmatron for simulation of re-entry conditions in a planetary atmosphere, XXXI ICPIG, XXXI International Conference on Phenomena in Ionized Gases, 2013-07-14/07-19, Granada (ES), Vol.1, pp.11-14, 2013
Abstract:

The experimental studies are carried out to adapt the plasmatron functioning to simulate re-entry conditions in a planetary atmosphere. The plasma flow is produced using argon or nitrogen arc and nitrogen or carbon dioxide is introduced into plasma jet. Although the gas introduced into plasma jet is injected behind the arc it influences the arc characteristics and dynamics of flow. This effect is studied in detail. Emission spectra of atomic nitrogen and ionized molecular nitrogen (N2+) are also recorded and analyzed. The atomic emission is studied in the infra-red region and has allowed the determination of an excitation temperature. The electron density is determined from the continuum radiation, and the rotational and vibrational temperatures are determined from the 1stnegative system of N2+

Affiliations:
Kamińska A.-other affiliation
Dudeck M.-CNRS (FR)
Hoffman J.-IPPT PAN
Szymański Z.-IPPT PAN
Vacher D.-Université d’Auvergne (FR)