Temperature Profile in YPO4 Laden Plasma Jet and Its Evolution with Arc Current and Powder Loading

Author(s):  
S. Bhandari ◽  
Y. Chakravarthy ◽  
V. C. Misra ◽  
T. Mahata ◽  
N. Tiwari ◽  
...  
1995 ◽  
Vol 416 ◽  
Author(s):  
Qingyu Wang ◽  
Jon L. Lindsay ◽  
David L. Hofeldt

ABSTRACTThe gas temperature of a radio-frequency thermal plasma has been measured by laser-induced fluorescence along the axis of the plasma jet near the substrate surface. The temperature was determined from the rotational population distribution of OH radicals. From the measured temperature profile, the freestream temperature was found to be about 3400 K and the boundary layer thickness was determined to be about 1 mm. A numerical model including carbonhydrogen- argon kinetics was used to predict species concentrations near the surface of the substrate. The results indicate that all CHa radical concentrations increase with freestream temperature for temperatures between 2500-4000 K. Of the C1 radicals, methyl has the highest concentration in this range in our system, which is consistent with other reports that methyl is an important diamond growth species.


Author(s):  
S. Janisson ◽  
A. Vardelle ◽  
J.F. Coudert ◽  
B. Pateyron ◽  
P. Fauchais ◽  
...  

Abstract In D.C. plasma guns used for plasma spraying, the properties of the plasma forming-gas control, to a great extent, the characteristics of the plasma jet and the momentum, heat and mass transfer to the particles injected in the flow. This paper deals with mixtures of argon, helium and hydrogen and the effect of the volume composition of these mixtures on the dynamic and static behavior of the plasma jet. Both were investigated from the measurements of arc voltage and gas velocity. Correlations between these parameters and the operating variables (arc current, gas flow rate, gas mixture composition) were established from a dimensional analysis. The results were supported by the calculation of the thermodynamic and transport properties of the ternary gas mixtures used in this study.


2020 ◽  
Vol 61 (4) ◽  
pp. 593-600
Author(s):  
M. B. Shavelkina ◽  
P. P. Ivanov ◽  
R. Kh. Amirov ◽  
A. N. Bocharov

1965 ◽  
Vol 20 (3) ◽  
pp. 465-474
Author(s):  
B. Ahlborn

A two-step model of the heating processes in a plasma jet is given. In this model, a hot interior and colder sheath is postulated, and the conservation theorems for mass, momentum and energy are solved so that the plasma velocity and temperature can be calculated if the power supply, pressure fall over the heating length, and the cross-sectional area of the luminous plasma stream are known. The accelerating action of the electromagnetic forces is considered as well as the J o u l e heating caused by the arc current. This model was tested by using a newly developed method to measure the average velocity and by using spectroscopy to measure the temperature of the plasma jet. The applicability of the “two step” model is shown by these experiments.


Author(s):  
Jinlu Yu ◽  
Liming He ◽  
Zhi Hu ◽  
Qian Zhang ◽  
Yang Xiao ◽  
...  

In recent past, the plasma-assisted ignition has been explored for applications on a variety of engines. The plasma ignition has been shown to possess special advantages such as reducing the ignition delay time, improving the reliability, and reducing the NOx emissions. By using a plasma jet ignition experimental system, the plasma jet ignition of argon-discharge arc has been investigated. Owing to the characteristics of high temperature, the mixture can be easily ignited by the plasma jet. Through the propane–air mixture ignition experiments, the ignition limits of the plasma jet and spark ignition are investigated. The results show that the plasma jet ignition could extend the ignition limits of propane–air mixture obviously. The ignition limit extends with the increase in the air flow rates. The average ignition limit (the gap between rich and lean limit) of spark ignition and plasma jet ignition are 2.34 and 2.57, respectively. The average ignition limit of the propane–air mixture extends by 9.8%. The plasma jet ignition limit extends with increasing arc current, and the degree of extending plasma jet ignition limit increases with increasing air flow rates. The average ignition limits of 5.7 A and 20.3 A are 2.57 and 2.79, respectively. The average ignition limit of the propane–air mixture extends by 8.5%. The plasma jet ignition limit extends with increasing argon flow rates. The average ignition limits of 200 L/h and 250 L/h are 2.79 and 3.08, respectively. The average ignition limit of the propane–air mixture extends by 10.4%.


1964 ◽  
Vol 18 (6) ◽  
pp. 166-170 ◽  
Author(s):  
P. A. Serin ◽  
K. H. Ashton

The effects of tangential gas flow, arc current, and water irascible solvents on the sensitivity of the plasma jet source, when used with aqueous solutions, have been studied. The optimum conditions for sensitivity have been established and the use of certain mixed aqueous/organic media have been found to improve the limits of detection significantly The effects of hydrochloric, nitric, and sulphuric acid were investigated and found to depend on the nature of the acid but not on the concentration. The matrix effect was found to be less severe than with many methods of excitation. Two examples of the application of the plasma jet to analytical problems are reviewed briefly.


2006 ◽  
Vol 45 (5B) ◽  
pp. 4355-4357 ◽  
Author(s):  
Tatsuya Okada ◽  
Seiichiro Higashi ◽  
Hirotaka Kaku ◽  
Naohiro Koba ◽  
Hideki Murakami ◽  
...  

2020 ◽  
Vol 23 (2) ◽  
pp. 1-6
Author(s):  
Ivan Peko ◽  
◽  
Bogdan Nedić ◽  
Marko Dunđer ◽  
Ivan Samardžić ◽  
...  

This paper presents Taguchi optimization of bevel angle in plasma jet cutting process of aluminium alloy EN AW 5083. Experimentations for this paper were carried out on the basis of standard L27 Taguchi's orthogonal array in which three plasma jet cutting parameters such as cutting speed, arc current and cutting height were arranged at three levels. From the analysis of means, analysis of variance and two-way interactions plot, significant plasma jet cutting process parameters and optimal combination of their levels that lead to minimal bevel angle were identified. The results showed that all three process parameters significantly affect bevel angle response. The predicted response at optimal plasma jet cutting conditions has a good fit with result of bevel angle from observed experiment.


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