阳极自冷却高效等离子体束流源

High Efficient Plasma Torch with Self-cooling Anode

研制了一种阳极自冷却的高效层流等离子体炬。利用工质气体在阳极内部循环冷却阳极,提高气体温度;再让加热后的气体以更高的定向速度流入放电腔,得到稳定的等离子体射流。试验中等离子体炬的总功率约为785W,在大气压环境工作,阳极无水冷,束流能够长时间稳定工作。稳态运行过程中,射流长度无明显变化,阳极温度保持在395℃。比对试验中非自冷式等离子体炬在阳极无水冷情况下,运行5 min后放电中断;在运行期间射流长度出现明显的变化,阳极明显烧红,温度高达750℃。试验表明阳极自冷却能够改善射流的稳定性,提高射流的长度,温度和焓值,是一种提高等离子体炬热效率和品质的重要技术之一。

We developed a plasma torch with self-cooling anode. The anode was cooled by forcing the working medium to flow through the internal of the anode, and the temperature of working gas would simultaneously increase by absorbing heat from the high-temperature anode. The heated gas then flowed into the discharging channel, and a stable plasma jet was obtained. The new plasma torch was tested with total input power at 785 W, under atmospheric pressure without water-cooling, and it could work stably in long-standing period. The length of the jet does not change notably, and the anode keeps a temperature at about 395 ℃. A traditional torch was also tested for comparison with 815 W input power without water-cooling. The temperature of the normal torch increases to 750 ℃ and shuts down after 5-minute operation in the air. The length of the plasma jet from a normal torch exhibits a quasi-period variation, observed by neck eyes clearly. The experimental results show that the self-cooling anode is an efficient way to achieve a stable plasma jet, and to increase the length, temperature and enthalpy of the jet. Self-cooling anode is a useful technique to improve the efficiency and quality of a plasma torch.