单元类型对焊接数值计算精度的影响  

Influence of element types on the accuracy of welding numerical simulation

作　　者：张立平[1] 房元斌 吴斌[1] 张红芳 占小红[3] 

机构地区：[1]江苏徐州工程机械研究院,江苏徐州221004 [2]徐州徐工随车起重机有限公司,江苏徐州221004 [3]南京航空航天大学,江苏南京211106

出　　处：《电焊机》2016年第11期88-91,110,共5页Electric Welding Machine

摘　　要：焊接数值模拟分析过程中,在保证网格质量的前提下,单元类型及网格类型的选择对计算结果的精确性产生明显影响。以大型有限元分析软件Marc为计算工具,采用四面体网格和六面体网格对平板对接接头进行离散,同时分别采用一阶单元和二阶单元进行分析。结果表明:四种单元类型下的焊接仿真变形趋势与实际焊接变形趋势一致,但是计算结果有较大差异。当焊接方法为MAG焊,网格尺寸为2 mm时,采用六面体8节点单元能较好地模拟焊接结构的变形情况。但是当焊缝位置网格尺寸发生变化时,如何选取单元类型需要进一步的分析。Different element types and element order have influence on the accuracy of welding numerical simulation under the same mesh quality. Using Marc software,flat butt joints are meshed by tetrahedral mesh and hexahedral mesh and analyzed by lower order element and high order element. The results show that simulation deformation trend is consistent with the actual weld distortion trend under different element types, but the calculation results have significant difference, When welding method is MAG and element size is 2 mm, an eight-node hexahedral element is appropriate for welding deformation. However, how to choose element type and element order need to be further studied when element size near welding bead changes.

关 键 词：数值模拟 单元类型 单元阶次 焊接变形 焊接残余应力 

分 类 号：TG404[金属学及工艺—焊接]