大型结构焊接件热-应力耦合仿真研究

Study on Thermal-Stress Coupling Simulation of Weldnents of Large Structures

以混流式水轮机蜗壳座环焊接为主要研究对象,板厚分别为90mm的座环与36mm的蜗壳以焊接方式实现连接,实际施工过程可能长达数月甚至数年的焊接时间,对于焊接数值仿真的计算也将长达数月,如何提高计算效率是一个值得研究的问题。基于ANSYS软件和APDL语言,对大型结构蜗壳座环焊接件进行热—应力耦合仿真分析,分别设置三种仿真模型,依据盲孔法实验数据选出最佳仿真方案,结果表明每层焊道数可以作为仿真时的简化手段,但要调整材料的导热系数,而模型和焊道层数尽量避免简化,该方法为其它大型结构焊接仿真提供了可靠的仿真过程和思路,并提高了计算效率。

Taking the welding of stay ring of Francis turbine volute as the main research object, the stay ring with the thickness of 90 mm and the volute with the thickness of 36 mm were connected by welding.The actual construction process may take months or even years, and the calculation of welding numerical simulation can take months.How to improve the calculation efficiency is a problem worthy of study.Based on ANSYS software and APDL language, the thermal stress coupling simulation analysis of large-scale structure spiral case stay ring weldment was carried out.Three kinds of simulation models were set up respectively, and the best simulation scheme was selected according to the experimental data of blind hole method.The results show that the number of weld beads in each layer can be used as the simplified hand during simulation, but the thermal conductivity of the material should be adjusted, and the simplification of the model and the number of weld beads should be avoided as far as possible.The method provides a reliable simulation process and idea for other large-scale structure welding simulation, and improves the calculation efficiency.