Effects of CO₂ molecules upon and argon thermal plasma

¹ Laboratoire Arc Électrique et Plasmas Thermiques, Université Blaise Pascal, 24 avenue des Landais, 63177 Aubière Cedex, France
² Département Mesures Physiques, IUT d'Aubière, Université d'Auvergne, 24 avenue des Landais, 63172 Aubière Cedex, France

Corresponding author: hubert.coitout@univ-bpclermont.fr

Received: 24 October 2003
Revised: 5 April 2004
Accepted: 15 April 2004
Published online: 5 August 2004

Abstract

The effects of CO₂ molecules upon an argon thermal plasma at atmospheric pressure are studied by optical emission spectroscopy. The excitation temperature, heavy particles temperature and electron density are measured as a function of Ar-CO₂ mixture composition and discharge current. The excitation temperature is ranging from 7000 K to 12000 K, electron density from 3 × 10²¹ m⁻³ to 5.6 × 10²² m⁻³ and heavy particles temperature of the peripherical region of the column from 6000 K to 7000 K. Excitation temperature and electron density gradients are evaluated. The influence of the arc confinement is studied and departure from local thermal equilibrium is also discussed.