基于VOF模型的移动TIG焊三维瞬态熔池行为分析  

Three-dimensional Transient Molten Pool Behavior Analysis of Mobile TIG Welding Based on VOF Model

作　　者：罗家元[1] 杨全 LUO Jiayuan;YANG Quan(College of Mechatronics and Vehicle Engineering,Chongqing Jiaotong University,Chongqing 400074,China)

机构地区：[1]重庆交通大学机电与车辆工程学院,重庆400074

出　　处：《热加工工艺》2020年第21期102-106,共5页Hot Working Technology

基　　金：重庆市教委科学技术研究项目(KJ1705129,KJQN201801610);重庆市博士后特别资助项目(Xm2017034);重庆交通大学山区桥梁结构与材料教育部工程研究中心开放式基金项目(QLGCZX-JJ2015-2);重庆第二师范学院校级科研项目(KY201701A);重庆市人文社科重点研究基地“重庆市统筹城乡教师教育研究中心”资助项目(18JDZDWT03)。

摘　　要：根据钨极惰性气体保护焊(TIG)实际的熔池情况,建立了移动热源作用下的三维瞬态熔池数值计算模型。考虑了熔池内部所受到的浮力、电磁力、Marangoni力等综合作用对熔池流场和温度场的影响,获得了各时段不同焊接电流TIG焊的熔池行为变化规律。结果表明,焊接熔池在电弧压力、电磁力、浮力和Marangoni力的共同作用下快速流动搅拌,使形成的焊缝较为均匀。在焊接热源移动过程中,熔池前端等温线被"压缩",热量密度较为集中,温度梯度较大。而尾部发生明显"拖尾",且热量分散,真实地反映了焊接熔池的演变。在此基础上,增大焊接电流后,熔池搅动增速,使得热量传播效率提升,引起了熔池体积增大。According to the actual molten pool of tungsten inert gas shielded welding(TIG), a three-dimensional transient numerical calculation model of molten pool under moving heat source was established. Considering the effects of buoyancy,electromagnetic force and Marangoni force inside the molten pool on the flow field and temperature field of the molten pool,the change law of the molten pool behavior in TIG welding under different welding current at different time periods was obtained. The results show that the welding molten pool can be rapidly agitated by the combined action of arc pressure,electromagnetic force, buoyancy force and Marangoni force, so that the weld formed is uniform. In the moving process of the welding heat source, the isotherm of the front end of the molten pool is compressed, the heat density is concentrated and the temperature gradient is large. The tail has obvious "trailing" and the heat is dispersed, which truly reflects the evolution of welding pool. On this basis, with the increase of welding current, the stirring speed of the molten pool increases, resulting in the increase of heat transfer efficiency and the volume of the molten pool.

关 键 词：TIG焊 VOF模型 熔池行为 FLUENT 

分 类 号：TG444[金属学及工艺—焊接]