基于SYSWELD催化转换器焊接温度场和应力场模拟

Numerical Simulation of Welding Temperature Field and Stress Field of Catalytic Converter Using SYSWELD Software

依据产品几何模型,运用VisualMesh网格划分软件分别建立了网格模型,通过对实际工艺参数和工艺特点的分析,建立了简化的数值模型,考虑了材料随温度变化的热物理性能和对流、辐射换热边界条件,给出了其焊接温度场演变历程和焊缝及其附近热循环曲线。同时实测了催化转换器焊缝附近的焊接热循环曲线,与模拟结果比较,两者基本吻合,证明了焊接温度场模拟结果的可靠性;并通过热-力耦合,将温度场结果施加到应力场,得到了残余应力分布规律,以及焊接变形量大小,与实测结果基本吻合。

Geometric models were established based on the product,and then their mesh models were built by using Visual Mesh software.Simplified numerical models were established with the analysis of actual process parameters and characteristics,which took the material properties with temperature and the heat transfer boundary conditions such as convection and radiation into account.Their temperature evolutions and thermal cycles nearby welding beads were given.Thermal cycles nearby welding beads of catalytic converter were measured,which were almost consistent with the simulation results.The welding temperature field simulations were credible.The results of the temperature fields were applied to the mechanical field with thermal-mechanical coupled.Welding residual stress fields and the welding deformation simulation results were given and analyzed quantitatively,which were almost consistent with measured values.