Numerical analysis of arc welding phenomena from a unified arc-electrodes model

统一电弧电极模型对电弧焊接现象的数值分析

基本信息

批准号：
13650779
负责人：
USHIO Masao
金额：
$ 2.18万
依托单位：
Osaka University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2001
资助国家：
日本
起止时间：
2001 至 2003
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13650779/
关键词：
Tungsten electrode Arc Weld pool TIG welding Numerical analysis Plasma Convective flow Simulation レーザ計測

项目摘要

The development of a numerical model of the process is quite useful for understanding quantitative values of the balances of mass, energy and force in the welding phenomena, because there is still luck of experimentally understanding the quantitative values of them due to the existence of complicated interactive phenomena between the arc plasma and the weld pool. This study was focused on a stationary tungsten inert gas (TIG) welding process for simplification, but the whole region of TIG arc welding, namely, tungsten cathode, arc plasma, work-piece and weld pool was treated in a unified numerical model because of taking the close interaction between the arc plasma and the weld pool into account. Calculations were made for stationary TIG welding at a current of 150 A. The anode was assumed to be a stainless steel, SUS304. The two-dimensional distributions of temperature and velocity in the whole region of TIG welding process were predicted. The weld penetration geometry was also predicted. Furthermore, quantitative values of the energy balance for the various plasma and electrode regions were given. The predicted temperatures of the arc plasma and the tungsten cathode surface were in good agreement with the experiments. There was also approximate agreement of the weld shape with experiment. The calculated convective flow in the weld pool was mainly dominated by the drag force of the cathode jet and the Marangoni force as compared with other two driving forces, namely, the buoyancy force and the electromagnetic force. It was shown that change in the direction of re-circulatory flow in the weld pool led to dramatically different weld penetration geometry.

该过程的数值模型的发展对于理解焊接现象中质量，能量和力量平衡的定量值非常有用，因为由于ARC Plasma和焊接池之间存在复杂的交互现象，实验中仍然存在实验性理解其定量值的运气。这项研究的重点是简化的固定钨惰性气（TIG）焊接过程，但是Tig Arc焊接的整个区域，即钨阴极，ARC等离子体，工件和焊接池在统一的数值模型中进行了处理，因为将ARC Plasma与ARC Plasma之间的密切相互作用进行了处理。对固定的TIG焊接进行了计算，在150 A的电流时进行了计算。假定阳极是不锈钢SUS304。预测了整个TIG焊接过程中温度和速度的二维分布。还预测了焊缝穿透性几何形状。此外，给出了各种等离子体和电极区域的能量平衡的定量值。 ARC血浆和钨阴极表面的预测温度与实验非常吻合。焊接形状与实验也有近似的一致性。与其他两种驱动力相比，焊接射流的阻力和Marangoni力的阻力主要由焊接池中计算出的对流流动，即浮力和电磁力。结果表明，焊接池的再循环流动方向的变化导致焊接渗透几何形状急剧不同。