Determination of temperature in a plasma jet emanating from a plasma torch with sectioned inter-electrode insert from the molecular emission spectrum of nitrogen

2011 ◽  
Vol 18 (4) ◽  
pp. 629-641 ◽  
Author(s):  
A. A. Mikhalchenko ◽  
E. V. Kartaev ◽  
V. I. Kuzmin ◽  
V. I. Nalivaiko ◽  
P. A. Chubakov
Keyword(s):  
Emission Spectrum ◽  
Plasma Torch ◽  
Plasma Jet ◽  
Molecular Emission

Anode Boundary Layer Effects in Plasma Spray Torches

2000 ◽  
Author(s):  
Z. Duan ◽  
J. Heberlein
Keyword(s):  
Boundary Layer ◽  
Plasma Torch ◽  
High Speed ◽  
Plasma Jet ◽  
Coating Quality ◽  
Gas Entrainment ◽  
Framing Rate ◽  
Mass Flow Rates ◽  
Cold Gas

Abstract The control over coating quality in plasma spraying is partly dependent on the arc and jet instabilities of the plasma torch. Different forms of instabilities have been observed with different effects on the coating quality. We report on an investigation of these instabilities based on high-speed end-on observation of the arc. The framing rate of 40,500 frames per second has allowed the visualization of the anode attachment movement and the determination of the thickness of the cold gas boundary layer surrounding the arc. The images have been synchronized with voltage traces. Data have been obtained for a range of arc currents, mass flow rates, for different gas injectors and for anodes displaying different amounts of wear. The analysis of the data has led to quantitative correlations between the cold gas boundary layer thickness and the instability mode for the range of operating parameters. The arc instabilities can be seen to enhance the plasma jet instabilities and the cold gas entrainment. These results are particular useful for guiding plasma torch design and operation to minimize the influence of plasma jet instabilities on coating properties.

Models of Thermodynamic Properties of Prominences

1979 ◽  
Vol 44 ◽  
pp. 349-355
Author(s):  
R.W. Milkey
Keyword(s):  
Thermodynamic Properties ◽  
Mass Transport ◽  
Emission Spectrum ◽  
Thermodynamic Parameters ◽  
Working Group ◽  
Physical Processes ◽  
Theoretical Concepts ◽  
Group 3 ◽  
Observational Techniques

The focus of discussion in Working Group 3 was on the Thermodynamic Properties as determined spectroscopically, including the observational techniques and the theoretical modeling of physical processes responsible for the emission spectrum. Recent advances in observational techniques and theoretical concepts make this discussion particularly timely. It is wise to remember that the determination of thermodynamic parameters is not an end in itself and that these are interesting chiefly for what they can tell us about the energetics and mass transport in prominences.

MOTION OF ANODE ATTACHMENT AND FLUCTUATIONS OF PLASMA JET IN DC ARC PLASMA TORCH

1997 ◽  
Vol 1 (2) ◽  
pp. 167-178 ◽  
Author(s):  
Milan Hrabovsky ◽  
M. Konrad ◽  
Vladimir Kopecky ◽  
J. Hlina ◽  
J. Benes ◽  
...  
Keyword(s):  
Plasma Torch ◽  
Plasma Jet ◽  
Arc Plasma ◽  
Arc Plasma Torch ◽  
Dc Arc ◽  
Dc Arc Plasma Torch

scholarly journals Power Dissipation of an Inductively Coupled Plasma Torch under E Mode Dominated Regime

Micromachines ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 834
Author(s):  
Nan Yu ◽  
Renaud Jourdain ◽  
Mustapha Gourma ◽  
Fangda Xu ◽  
Adam Bennett ◽  
...  
Keyword(s):  
Power Dissipation ◽  
Inductively Coupled Plasma ◽  
Plasma Torch ◽  
Electrical Response ◽  
Inductively Coupled ◽  
De Laval Nozzle ◽  
Surface Fabrication ◽  
Icp Torch ◽  
Frequency Power

This paper focuses on the power dissipation of a plasma torch used for an optical surface fabrication process. The process utilizes an inductively coupled plasma (ICP) torch that is equipped with a De-Laval nozzle for the delivery of a highly collimated plasma jet. The plasma torch makes use of a self-igniting coil and an intermediate co-axial tube made of alumina. The torch has a distinctive thermal and electrical response compared to regular ICP torches. In this study, the results of the power dissipation investigation reveal the true efficiency of the torch and discern its electrical response. By systematically measuring the coolant parameters (temperature change and flow rate), the power dissipation is extrapolated. The radio frequency power supply is set to 800 W, E mode, throughout the research presented in this study. The analytical results of power dissipation, derived from the experiments, show that 15.4% and 33.3% are dissipated by the nozzle and coil coolant channels, respectively. The experiments also enable the determination of the thermal time constant of the plasma torch for the entire range of RF power.

scholarly journals On the violation of local thermodynamic equilibrium in the plasma jet of an argon arc two-jet plasmatron

2019 ◽  
Vol 85 (1II)) ◽  
pp. 145-150
Author(s):  
A. S. Cherevko ◽  
A. A. Morozova
Keyword(s):  
Energy Level ◽  
Equilibrium State ◽  
Thermodynamic Equilibrium ◽  
Local Thermodynamic Equilibrium ◽  
Plasma Jet ◽  
Saha Equation ◽  
Radiation Processes ◽  
Unconventional Method

The degree and nature of the violation of local thermodynamic equilibrium (LTE) in the analytical zone of a plasma jet generated by an argon arc two-jet plasmatron (TJP) was estimated using an unconventional method based on determination of the nonequilibrium parameterbiequal to the ratio of the experimentally determined actual population of the energy level (ni) of the element to the population of the same level calculated from the Saha equation (nis). Partial ionizing deviation of plasma under study from the equilibrium state takes place only when low-lying atomic levels are overpopulated. The distinct dependence ofbion the ionization potential of the considered element (e.g., Ca, Mg, and Be) is shown. The results were interpreted in the light of the increasing role of radiation processes upon excitation of spectra in the argon arc two-jet plasmatron.

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