基于子模型技术的四种点焊结构建模方法研究

Research on Four Modeling Methods of Spot Welding Structure Based on Sub-model Technology

针对目前常见的4种焊点模拟单元,本文运用子模型技术选取某不锈钢地铁车的12个参考点为研究对象,分别建立4种焊点有限元模型。对比4种单元的建模过程及12个参考点在AW3+纵向压缩800Kn静强度工况下的仿真应力水平和试验应力水平,结果表明:ACM单元的模拟平均误差为4.06%,模拟精度最高,但该单元结构复杂,整车建模时网格规模较大,适合关键部件的精细研究;Rbe2单元的模拟平均误差为9.89%,其本质相当于刚度无穷大的杆,模拟精度最低;Beam单元和Cweld单元建模都较简单,模拟平均误差分别为6.55%和7.87%,整车建模时可使用beam单元。

Aiming at the four kinds of common solder joint simulation elements,this paper uses the sub-model technology to select 12 reference points of a stainless steel subway car as the research object to establish four kinds of solder joint finite element models.The simulation stress level and test stress level of four kinds of element modeling process and 12 reference points under the static strength condition of AW3+longitudinal compression 800Kn are compared.The results show that the average simulation error of the ACM element is 4.06%,and the simulation accuracy is the highest,but the structure of the element is complex,and the grid scale of the whole vehicle modeling is large,which is suitable for detailed research of key components;the average simulation error of the Rbe2 element is 9.89%,which is essentially equivalent to a rod with infinite stiffness,and the simulation accuracy is the lowest.The modeling of Beam element and Cweld element is relatively simple,and the average simulation error is 6.55%and 7.87%.Beam element can be used in vehicle modeling.