焊接数值模拟中以温度为控制变量的高效算法

A high-efficiency welding simulation method based on welding temperature

关键词:  焊接  数值模拟  快速计算  分段热源

Key words:  welding  numerical simulation  high-efficiency simulation  line-gauss heat source

摘要:

对焊接数值模拟中的各种加速计算方法进行了细致研究,并在分段热源法的基础上提出了温度函数法.和分段热源法相比较,温度函数法将焊接数值模拟中的控制变量由热量转变为温度,增加了焊接温度场的可控制性,并提高了模拟温度场在模型宽度和厚度方向与实际焊接温度场的一致性.文中通过铝合金薄板搅拌摩擦对焊的模型对温度函数法进行验证.结果表明,温度函数法得到的残余应力和变形结果与移动热源方法得到的结果具有一致性,并且和实际试验测量结果吻合,计算效率有大幅度的提高,能够达到工程应用的需要.

Abstract:

A lot of computed methods which improve the efficiency of welding simulation were discussed, and base on line-gauss heat source model, a new method was presented which was called temperature function method.Compared with line-gauss heat source model, the control variable in temperature function method was changed from heat input to welding temperature, which led to more consistent between welding temperature field from simulation and experiment in width and thickness direction of model.This new high-efficiency simulation method was validated by a model of friction stir welding on Al alloy sheet in this paper.The simulation results show that not only the residual stress and distortion of the sheet from temperature function method is similar with that from moving heat source model method, which is validated by the experimental results, but also the efficiency of new method is significant increased, and achieves the time request of welding simulation in engineering application.