Use of “lattice Boltzmann” – like resolution methods to simulate atmospheric blown plasma jets for spray process.

In a scientific context in which flow modeling seems to be a well-resolved issue thanks to the growing power of computing machinery and the improvement of numerical technologies, new calculation concepts are appearing. Typically, these are resolution methods initially resulting from the cellular robot technology (lattice gas) and whose autonomous theoretical development has been growing for about twenty years. They are named “Lattice Boltzmann method” (LBM)

These algorithms create a keen interest because of:

• Their ability to enable spectacular visual representations of scalable phenomena.
• Their “particulate” aspect.
• Their implementation based on elementary phenomenological rules.
• Their potential to inform of boundary conditions on complex surfaces (granular, porous, diphasic environments).
• Their ability to allow the “parallel” execution of computations.

These methods seem to be absolutely usable to simulate a plasma jet of thermal spraying along with the interaction with the carried powdery matter.

However, in practice, a few problems are remaining, as for instance:

• The LBM don’t show enough thermal exchanges, although these are fundamental in a blown arc plasma jet.
• How to explain transport gradient properties: viscosity, thermal conductivity, etc ?
• How to show the axial symmetry of the jet, in order to reduce computation times?

These are problems for the scientific community, and we have proposed some solutions based on the example of a binary gas jet (argon-hydrogen) immersed in a similar atmosphere. To do so, we have modified the standard equation of the LBM model for the jet asymmetry to be considered. The turbulence is represented according to a Smargorinsky model and thermodynamics and gas transportation properties are extracted from T&TWinner (http://ttwinner.free.fr).

According to the first conclusions, these methods seems to be competitive with those already existing in Jet&Poudres (see figure 1, figure 2) and additional performance gains are expected concerning the representation of jets seeded with particles.

The activity of the scheme focuses on these following points:

• The Jets&poudres project itself (more than 200 downloads per years)
• T&TWinner, calculation and data bases of thermodynamics and transportation properties (put online in December 1999 and more than 600 downloads in 2009),
• The Stochas project for the 3D reconstitution of a non-homogeneous or a porous material (deposit there) from microscopy images and estimation of the thermodynamics properties through the Lattice Boltzmann method.

1. R. Djebali, B. Pateyron, M. El Ganaoui, H. Sammouda
   Axisymmetric high temperature jet behaviours based on a lattice Boltzmann computational method. Part I: Argon Plasma
   International review of Chimical Engineering, vol. 1, n. 5 pp. 428-438
   
   
2. Meillot, E., Vardelle, A., Coudert, J.F., Pateyron, B., Fauchais, P.
   Plasma spraying using Ar-He-H2 gas mixtures
   1^st Proceedings of the International Thermal Spray Conference, 803-808 (1998)
   
   
3. B. Pateyron, G. Delluc and N. Calvé
   T&TWinner, the chemistry of non-line transport properties in interval 300K to 20000 K
   Mécanique et industries 6 (2005) 651-654
   
   
4. B. Pateyron, G. Delluc and P. Fauchais
   Chemical and transport properties of carbon-oxygen hydrogen plasmas in isochoric conditions
   Plasma Chemistry and Plasma Processing 25 (2005) 485-502
   
   
5. B. Pateyron
   ADEP - Thermodynamic and transport properties Data Base
   Codata Newsletter November (1993)
   
   
6. Pateyron, B., Elchinger, M.F., Delluc, G., Fauchais, P.
   Sound velocity in different reacting thermal plasma systems
   Plasma Chemistry and Plasma Processing 16 (1996) 39-57
   
   
7. B. Pateyron, M.F. Elchinger, G. Delluc, P. Fauchais
   Sound velocity in different reacting thermal plasma coatings
   Plasma Chemistry Plasma Processing 16 (1), p 39-57, (1996)
   
   
8. W.L.T. Chen, J. Oberlein, E. Pfender, B. Pateyron, G. Delluc, M.F. Elchinger, P. Fauchais
   Thermodynamic and transport properties of argon/helium plasmas at atmospheric pressure
   Plasma chemistry and plasma processing, 15 (3), p 559-579, (1995)
   
   
9. B. Pateyron and G. Delluc
   Logiciel TT Winner, ADEP Banque de données de l’Université de Limoges et du CNRS
   (Ed.) Direction des bibliothèques, des Musées et de l’Information Scientifique et technique, France (1986),
   disponible sur le site http://ttwinner.free.fr
   "Jets&Poudres" free downlowd from http://www.unilim.fr/spcts or http://jets.poudres.free.fr
   
   
10. B. Pateyron
    "Code ADEP - Chimie sur Minitel"
    Le Journal du CNRS Mai 1992, LMCTS "ADEP-Junior" Fiche logiciel L’actualité chimique N° 3 Mai-juin 1993, Anonyme "ADEP - Thermodynamic and transport properties Data Base" Codata Newsletter November 1993
    "T&TWinner" free downlowd from http://www.unilim.fr/spcts or http://ttwinner.free.fr