压力对双射流电弧等离子体特性的影响  

Effects of pressure on the characteristics of dual-jet dc arc plasmas

作　　者：吴贵清[1] 葛楠[1] 杨安[1,2] 李和平[1] 包成玉[1] 

机构地区：[1]清华大学工程物理系,北京100084 [2]南方医科大学生物医学工程学院,广州510515

出　　处：《清华大学学报（自然科学版）》2014年第1期68-72,83,共6页Journal of Tsinghua University(Science and Technology)

基　　金：国家自然科学基金资助项目(11035005)

摘　　要：该文采用实验测量方法研究了气体压力对双射流直流电弧等离子体弧电压、放电稳定性及等离子体电弧-射流区二维投影温度场的影响规律。通过引入可见光测温技术,对不同工况下的热等离子体放电图像进行采集,并采用二值化阈值分割方法求取投影温度场对应的等灰度线,利用8方向Freeman链码对特定边界进行描述,从而对热等离子体电弧-射流稳定性进行评估。研究结果表明:在其他参数保持不变的情况下,随着反应器内工作压力的降低,电弧-射流区二维投影温度场高温区面积增大,同时,电弧的稳定性也会受到一定影响;但随着工作气体流量的增大,反应器内工作压力对电弧-射流二维投影温度场高温区面积变化的影响减弱;在本文实验研究参数范围内压力对弧电压的影响较小。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 stahilities 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 theparameter ranges studied in this paper.

关 键 词：压力 双射流热等离子体 电弧 

分 类 号：TK124[动力工程及工程热物理—工程热物理]