GMAW熔滴过渡行为数值分析及试验验证  

Numerical simulation and experimental verification of droplet transfer behavior in GMAW

作　　者：丁雪萍[1,2] 李桓 

机构地区：[1]中国科学院重庆绿色智能技术研究院,重庆401122 [2]智能增材制造技术与系统重庆市重点实验室,重庆400714 [3]天津大学天津市现代连接技术重点实验室,天津300072

出　　处：《焊接学报》2017年第12期73-76,113,共5页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目(51175374);重庆市基础科学与前沿技术研究一般项目(cstc2016jcyj A0059);先进焊接与连接国家重点实验室面上项目(AWJ-M16-03)

摘　　要：基于FLUENT软件,考虑热分析,选用VOF模型,针对纯氩气保护直流熔化极气体保护焊(GMAW)熔滴过渡行为进行数值模拟,分析熔滴过渡不同时刻对应电弧温度、电势、热通量等物理量的变化规律.结果表明,电弧最高温度呈现周期性变化趋势;电势分布随着熔滴行为变化而变化,而在熔滴脱落之后,电流不再流经脱落熔滴.热通量最大值出现在中心部位,沿径向距离减小.为验证模拟结果准确性,开展焊接试验,利用Lab VIEW信号采集系统采集焊接电流和电弧电压波形,借助高速摄像设备拍摄实时电弧形态和熔滴过渡过程,从而有效、定量验证模拟结果准确性.比较结果表明模拟结果同试验结果二者吻合良好,文中熔滴过渡数学模型是合理的.The droplet transfer in GMAW was simulated based on FLUENT software. A two-dimensional axisymmetric model of droplet transfer was developed considering thermal analysis. The distribution of physical quantities,including temperature,electric potential and heat flux on the workpiece,was investigated at different stages of droplet transfer. The results showed that the maximum arc temperature displayed a periodic trend. It is found that the electrical potential changed with droplet behavior and the current did not flow through the detached droplet. The heat flux decreased from the axis to the boundary and the maximum value occurred at the center. To verify the accuracy of simulated results,the welding experiments were performed. The actual droplet transfer was recorded with high-speed photography while the waveforms of welding current and arc voltage were acquired through Lab VIEW signal acquisition system.The comparison showed that the simulated results agreed well with the experimental ones. It was demonstrated that the established mathematic model for droplet transfer was reasonable.

关 键 词：熔化极气体保护焊 熔滴过渡 数值分析 高速摄像 

分 类 号：TG444.7[金属学及工艺—焊接]