船舶甲板分段纵骨焊接变形和残余应力数值模拟

基于非线性分析软件Abaqus,采用顺序耦合的热弹塑性有限元方法研究典型船舶甲板分段纵骨焊接的变形与残余应力问题。焊接过程中的温度场分析采用具有截面积分shell单元的shell/solid模型,移动热源为高斯分布与均匀体组合热源,材料考虑应变随温度变化的特性。通过与T型接头焊接实验结果对比,验证了方法的可靠性。在此基础上,计算分析了甲板分段纵骨焊接的整体变形和局部板格变形,并讨论了外板纵向和横向焊接残余应力分布规律。

Numerical Simulation of Welding Distortion and Residual Stress of Longitudinals of a Deck Grillage

In this article, the welding distortion and residual stress of a deck grillage are studied through a thermal elastic-plastic finite element method based on shell/solid model. In the sequentially coupled analysis, the shell/solid model is adopted to model the deck structure and the combined heat source and temperature-dependent material properties are employed in the thermal analysis. The accuracy of the approach is verified by the comparison of a tee joint welding simulation results with experimental values. FE model of the deck grillage is built up, and the welding induced distortion and residual stress is simulated by the proposed method.