TIG焊接熔透熔池的数学模型

Mathematical Modeling of TIG Molten Pool with Full-penetration

关键词:  TIG熔透熔池  表面变形  流体流动  传热  数学模型

Key words:  full-penetration weld pool  pool-surface deformation  fluid flow  heat trasfer  mathematical modeling

摘要:

根据流体力学理论和变分法原理,推导出了熔透情况下TIG焊接熔池上表面和下表面变形的方程。建立了TIG焊接熔透熔池流场与热场的数值分析模型,采用非正交贴体曲线坐标系成功地处理了熔池表面的曲面边界。将熔透情况下熔池上下表面变形的计算,与熔池流场与热场的计算相结合,不仅较好地计算出了熔池的流场与热场,同时求得了焊接熔池的上下表面变形。焊接工艺试验表明,根据该模型计算的焊缝成形与试验测试结果吻合程度良好。

Abstract:

The calculating formulas of top and bottom pool-surface deformation in TIG full-penetration weld pool is developed based on principles of fluid mechanics and variation calculus. A mathematical model has been estabished for the fluid flow and heat transfer in TIG full-penetrated Weld pool.Difficulties associated with irregular shape of the deformed weld pool surface have been sucessfully overcome by calculating the surface deformation together with the fluid flow and heat transfer in weld pools. Data of fluid velocity and temperature distribution in weld pools are obtained, so do that of top and bottom pool-surface deformation. TIG welding experiments show that the predictions of the model have a good agreement with the experimental observation with respect to weld pool shape.