Numerical study of an ArH2 gas mixture flowing inside and outside a dc plasma torch

Citation
P. Eichert et al., Numerical study of an ArH2 gas mixture flowing inside and outside a dc plasma torch, J THERM SPR, 7(4), 1998, pp. 505-512
Citations number
26
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Material Science & Engineering
Journal title
JOURNAL OF THERMAL SPRAY TECHNOLOGY
ISSN journal
1059-9630 → ACNP
Volume
7
Issue
4
Year of publication
1998
Pages
505 - 512
Database
ISI
SICI code
1059-9630(199812)7:4<505:NSOAAG>2.0.ZU;2-E
Abstract
The flow of gas mixtures in a de plasma torch is studied using the CFD PHOE NICS (CFD PHOENICS, Berkeley, CA) code, In the model, the cold gas mixture (300 K), initially constituted of 85 vol% Ar and 15 vol% H, is introduced i nto a power input zone where it takes energy and is ejected in the surround ing atmosphere at constant pressure (10(5) Pa). The flow is assumed to be i n chemical equilibrium. Equations of mass, momentum, and energy are discret ized using a control-volume method. The turbulent flow is modeled by a k-ep silon two-equations model for the turbulent kinetic energy and its dissipat ion rate. Finally, the algebraic coupling equations set is solved by means of the SIMPLEST algorithm, implemented into the CFD code, using a hybrid in terpolation scheme. Results concern the effect of the torch power on the Ar H2 flow. The phenomenon is analyzed through the evolution of velocity and t emperature inside and outside the torch. From these calculations, the effec t of ambient gas entrainment by the jet is emphasized and a comparison of t he level of entrained gas is made with experimental data.