Heat Transfer Mechanisms in Arcs of Various Gases at Atmospheric Pressure
نویسندگان
چکیده
Abstract This work expands findings about the dominant heat transfer mechanisms in argon and helium arcs at atmospheric pressure for monoatomic (Ar, He, 50% Ar–50% He), diatomic (air, $${\hbox{N}}_{2}$$ N 2 , $${\hbox{O}}_{2}$$ O $${\hbox{F}}_{2}$$ F $${\hbox{Cl}}_{2}$$ Cl ), triatomic ( $${\hbox{CO}}_{2}$$ CO ) gases. The objective is to understand plasmas through validated numerical modeling GTAW welding process. Arcs of all gases have lengths 10 mm 200 A current. Five are considered: Joule heating, convection, radiation, conduction, Thomson effect. Results indicate that general structure qualitatively similar gases; sizes change depending on gas. energy input near cathode while anode convection. output always follows same sequence: effect next followed by radiation arc column, conduction anode. heating most significant Ar, it has lowest significance. due differences electric conductivity He (higher up 21,000 K lower beyond than other gases) high viscosity which creates a small versus large convection region. transfers towards lowest; enthalpy compared . Finally, Ar radiative emission smallest their net coefficient.
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ژورنال
عنوان ژورنال: Plasma Chemistry and Plasma Processing
سال: 2023
ISSN: ['0272-4324', '1572-8986']
DOI: https://doi.org/10.1007/s11090-023-10328-9