This paper experimentally studies the influence of the operation pressure on arc voltages, discharge stabilities and projective areas of dual-jet dc arc 2-D high-temperature plasma regions. The visible pyrometry, the contour extraction method with the variable binary thresholding technique, and an eight-direction Freeman chain coding technique were used based on the recorded digital discharge images to quantitatively in situ describe the 2-D grayscale contour distributions of the arc-jet plasmas and the discharge stabilities during discharge processes. Experimental results show that with other parameters being unchanged, the 2-D high-temperature region of the arcjet increases with decreasing operation pressure, which also affects the discharge stabilities of the plasmas. The results also show that with increasing argon flow rate, the differences of the arcjet 2-D high-temperature region areas at different operation pressures decease, while the influences of the operation pressure on the arc voltage are not significant within the parameter ranges studied in this paper.
吴贵清, 葛楠, 杨安, 李和平, 包成玉. 压力对双射流电弧等离子体特性的影响[J]. 清华大学学报（自然科学版）, 2014, 54(1): 68-72.
Guiqing WU, Nan GE, An YANG, Heping LI, Chengyu BAO. Effects of pressure on the characteristics of dual-jet dc arc plasmas. Journal of Tsinghua University(Science and Technology), 2014, 54(1): 68-72.
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