GTAW熔池形状数值模拟精度的改进

Improvement on numerical simulation precision of GTAW weld pool geometry

关键词:  熔池形状  熔池尾部后拖  热源分布模式  数值模拟  钨极氩弧焊

Key words:  weld pool geometry  rear trailing of weld pool  distribution mode of heat source  numerical simulation  gas tungsten arc welding

摘要:

采用高斯分布或双椭圆分布热源模式对GTAW熔池形状的数值模拟中发现,计算得到的熔池尾部形状与实际情况有较大差别。文中分析了误差产生原因,提出了数值模拟程序设计中如何确定热源在工件上作用区域计算半径的三个原则。解决了计算结果中熔池尾部后拖不足的问题,提高了GTAW熔池形状数值模拟精度。

Abstract:

It has been found that when the Gaussian or Double-elliptic mode of heat flux distribution was employed in numerical simulation of GTAW(gas tungsten arc welding) welding pool behaviors there was marked difference between the predicted and practical pool geometry at the rear of weld pool.The reason why such difference exists was analyzed,and three principles guiding how to determine the calculating zone of heat source on the work piece were put forward in designing the numerical simulation program.Through appropriate selecting the calculating zone radius of welding arc on the work piece and making it matched with the distribution parameters of Double-elliptic mode of heat flux,the trailing problem of weld pool rear in previous models had been successfully solved,and the numerical simulation precision had been greatly improved for GTAW weld pool geometry.