Numerical simulation of influence of nozzle structure on arc characteristics of GPCA-TIG welding  

作　　者：Huang Yong Ren Qinglong Lu Suzhong Ren Cao Feng Wei 黄勇;任青龙;陆肃中;任操;冯伟(State Key Laboratory of Advanced Processing and Recycling of Non-Ferrous Metals,Lanzhou University of Technology,Lanzhou 730050,China;Harbin Wolding Institute Limited Compary,Harbin 150028 China)

机构地区：[1]State Key Laboratory of Advanced Processing and Recycling of Non-Ferrous Metals, Lanzhou University of Technology, Lanzhou 730050 ,China [2]Harbin Wolding Institute Limited Compary,Harbin 150028 China

出　　处：《China Welding》2018年第3期11-19,共9页中国焊接（英文版）

基　　金：supported by National Natural Science Foundation of China(Grant No.51265029)

摘　　要：This work mainly articulated the effects of nozzle structure on arc characteristics in gas pool coupled activating TIG （GPCA-TIG） welding process by using Fluent Software. Different models were set up to adapt the different torch structure during computer progress. The specific configuration of the welding torch made the gas flow in outer gas passage constrained. The nozzle structure has great influence on outer gas distribution because of the changing of coupling region between the outer active gas and molten pool surface. When the coupling degree is reduced or the outer gas passage become smaller, the oxygen in outer gas penetrates into the arc plasma and spreads to the arc region more easily. Owing to its cooling effects, the morphology of arc is contracted, and the arc temperature is increased. When the inner wall and the outer wall of outer gas passage are not parallel, the wide top and narrow bottom nozzle shape can bring more oxygen into the arc plasma, the arc is contracted and the peak temperature of arc rises a little more comparing to the narrow top and wide bottom one.This work mainly articulated the effects of nozzle structure on arc characteristics in gas pool coupled activating TIG （GPCA-TIG） welding process by using Fluent Software. Different models were set up to adapt the different torch structure during computer progress. The specific configuration of the welding torch made the gas flow in outer gas passage constrained. The nozzle structure has great influence on outer gas distribution because of the changing of coupling region between the outer active gas and molten pool surface. When the coupling degree is reduced or the outer gas passage become smaller, the oxygen in outer gas penetrates into the arc plasma and spreads to the arc region more easily. Owing to its cooling effects, the morphology of arc is contracted, and the arc temperature is increased. When the inner wall and the outer wall of outer gas passage are not parallel, the wide top and narrow bottom nozzle shape can bring more oxygen into the arc plasma, the arc is contracted and the peak temperature of arc rises a little more comparing to the narrow top and wide bottom one.

关 键 词：gas pool coupled activating TIG welding numerical simulation nozzle structure arc characteristics 

分 类 号：TG444.74[金属学及工艺—焊接]