基于热弹塑性有限元法船舶薄板结构焊接变形模拟与预报

摘要

本文论述了基于热弹塑性有限元法对不同焊接顺序下薄板焊接变形的模拟和预报,介绍了模拟过程中关键问题的处理,如材料相变的应对措施,移动热源的加载过程的模拟,生死单元法在焊缝生成模拟中的应用.本文以T型构件两侧角焊缝为研究对象,设计4个常用焊接顺序,利用Ansys分别模拟不同顺序下的焊接过程,并进行热弹塑性有限元分析,根据温度场与合位移场分布情况,得出焊接变形的最小的最佳焊接顺序.说明基于热弹塑性有限元法可以实现不同焊接顺序下焊接变形的模拟和预报.计算结果与实测一致.%This paper discusses the simulation and prediction of welding deformation under different welding se-quences based on the thermal elastic-plastic finite element method, introduces how to deal with the key problems, such as the treatment of phase transition problem, simulation of the generation process of welding lines and the application of the meth-od of Birth and Death in welding simulation; Taking the fillet welds of the T-type component that is common in ships as an example as the research object. Designing four commonly used welding sequences.The welding process is simulated by ANSYS, and the thermal elastic-plastic finite element analysis of welding deformation under different welding sequences is conduc-ted. On the basis of the distribution of the temperature field and the displacement field, the optimum welding sequence of de-formation is obtained, which instructs that the simulation and prediction of welding deformation under different welding se-quences can realize based on thermal elastic-plastic finite element method. The calculated results are in line with the actual results.