基于Fluent的熔融金属填充焊接冲蚀孔形成过程数值模拟

Numerical simulation of formation of hole due to flow of molten metal in welding based on Fluent

针对熔融金属填充焊接工艺过程中液流冲蚀形成小孔的过程进行数值模拟研究.分析确定该过程的控制方程和边界条件,建立二维轴对称模型.利用Fluent软件,从物理过程出发建立凝固熔化模型以及热源模型.利用VOF模型追踪金属相与气相界面,获得液流在不同的焊接条件下,冲蚀形成小孔的过程.并通过获得的流场,温度场分析形成不同形貌小孔的原因.利用锡铅合金为试验材料在堆焊过程中得到的焊缝截面形貌,试验结果表明,模拟计算得到结果与试验结果基本吻合.

The formulation of hole due to the flow of molten metal during welding was numerically simulated. A two-dimensional axial symmetric model was established by determining the control equations and boundary conditions after analyzing the physical process of welding. Melting and solidification model and heat source model were built based on commercial software Fluent. The interface between the metal and gas phases was tracked using VOF model,which induced formation of holes in fluid flow on sheets with different thicknesses. The reasons of shaping holes was analyzed with the fluid flow field and temperature field. The microstructure of bead weld was observed with tin-lead alloy as experimental material,and it shows that the simulated results agreed well with the measured results.