Investigation on thermo-mechanical behavior of continuous casting slab based on element-free Galerkin method
SUN Cong-lei1,2, CAI Lai-qiang1,2, WANG Xu-dong1,2, YAO Man1,2
1. School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024, Liaoning, China; 2. Key Laboratory of Solidification Control and Digital Preparation Technology (Liaoning Province), Dalian University of Technology, Dalian 116024, Liaoning, China
Abstract：Compared with the numerical computation method based on grid discretization,the meshless method avoids the problems of complex topology structure,element numbering and information transfer by replacing the grid with discrete nodes,and shows great flexibility in simulation and analysis of movement interface of phase transition,large deformation and dynamic crack propagation. A field variable approximation function is constructed based on the moving least squares method. According to the heat transfer characteristics of continuous casting slab during the initial solidification in mold,the control equation of thermo behavior of continuous casting slab based on element-free Galerkin method are constructed and derived. Then combined with the weak form of Galerkin integral and the variation principle,the thermal elastoplastic model for two-dimensional cross-section slab is established. Taking the heat flux calculated inversely from the measured temperatures of copper plate as boundary conditions,the non-uniform heat transfer,stress and strain of initial solidified shell inside mold are simulated and analyzed. The results show that in the width direction of mold,thermo-mechanical behavior shows significant non-uniform characteristics. The stress-strain increases rapidly within 200 mm from the meniscus,and then the growth rate of stress-strain slows down. At 550 mm from the meniscus,the equivalent stress-strain appear maximum values,which are 15.97 MPa and 0.76%. In the width direction,due to the influence of two-dimensional cooling,the temperature of the corner decreases rapidly and the phenomenon of stress concentration appears. However,there is a low valley of stress-strain in the adjacent deflection corner,which is different from the corner in temperature,stress and strain. The results verify the feasibility and applicability of the meshless method to calculate the non-uniform heat transfer and mechanical behavior for continuous casting process,and provide a basis and reference for the application of the meshless method to the research of formation and propagation of slab cracks.
孙聪磊, 蔡来强, 王旭东, 姚曼. 基于无网格伽辽金法的板坯传热及力学行为[J]. 钢铁, 2022, 57(10): 91-100.
SUN Cong-lei, CAI Lai-qiang, WANG Xu-dong, YAO Man. Investigation on thermo-mechanical behavior of continuous casting slab based on element-free Galerkin method[J]. Iron and Steel, 2022, 57(10): 91-100.
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