双丝三电弧焊热源优化及数值模拟

为研究双丝三电弧焊焊接温度散布规律，根据其电弧形态和脉冲频率建立了适用于双丝三电弧焊接的体+面热源，并根据焊丝的倾角对其进行了旋转计算，利用有限元技术模拟了6 mm厚Q235碳素钢的双丝三电弧焊焊接温度场，通过遗传算法对其热源参数进行了迭代优化，提高了计算效率。计算结果表明：温度场呈长椭圆状分布，且最高温度和最大温度梯度都出现在R弧热源处，其原因是此处同时积累了R弧电弧热量和L弧焊后凝固时的热量；有限元模型温度场与实验温度场结果对比吻合度较高，其结果可为拓展双丝三电弧焊的应用和优化工艺参数提供仿真基础。

Heat source optimization and numerical simulation for tri-arc twin wire welding

The temperature distribution rule of tri-arc twin wire welding was studied. According to the arc pattern and pulse frequency, a body+surface heat source model for tri-arc twin wire welding was established, and rotation transformation was performed based on the tilt angle of wire. The finite element technology was used to simulate the temperature field of 6 mm thick Q235 carbon steel under tri-arc twin wire welding, and genetic algorithm was introduced for iterative optimization of its heat source parameters, so as to improve the calculation efficiency. Calculation results showed that the distribution pattern of temperature field was in a long elliptical shape, and the highest temperature and maximum temperature gradient appeared at the R-arc heat source area, which was due to the accumulation of both R-arc heat and the L-arc heat during post-weld solidification. The temperature field of finite element model was highly consistent with that in the experiment, which provides basis for expanding the application of tri-arc twin wire welding and optimizing process parameters.