Automatic Mesh Generation And Thermal-mechanical Coupling Analysis Of Complex Structural Component

Complex structural components are widely used in aerospace,nuclear reactors,mechanical,microelectronic semiconductor,and other fields of engineering,its structural safety and reliability design is the basis of normal work.When a complex structural component is working,its heat transfer will influence the structural deformation.In contrast,the internal energy generated by the structural deformation will impact its heat transfer process,and the interaction between heat transfer and structural deformation is a thermal-mechanical coupling process.This paper adopts the numerical simulation method to study automatic mesh generation and thermal-mechanical coupling analysis of complex structural components.The results are as follows:(1)The basic theory and algorithmic principle of the Delaunay triangulation algorithm and the Advancing front technique in mesh generation are studied.For the Delaunay triangulation algorithm,the Delaunay triangulation network of all internal points is generated based on the point-by-point insertion method,which satisfies the empty circumscribed circle and maximization and minimum angle criteria.The boundary is discretized according to the global grid size control function for the Advancing front technique.The triangle element is generated recursively from the boundary to the inner normal direction.After the grid is generated,the edge exchange and joint moving methods are applied to optimize the grid topology.The quality of the grid is evaluated by the triangle side length index and shape index.(2)The feature recognition algorithm is introduced to set the grid size of different scale regions of the complex structural components' model.The complex structural components' model decomposes based on the Delaunay triangulation algorithm and the Advancing front technique.Finally,the overall complex structural components' mesh model is formed by connecting and transitioning regional grids of different scales through geometric exponential control function.Through the automatic grid generation of NACA1410-D wing,pressing die of mobile phone chip,heat pipe cooled nuclear reactor are compared with the results generated by ANSYS software,It is showed that the meshing time of the grid is close to those of ANSYS software,the maximum error between the average mesh quality and ANSYS software is 11%,and the overall mesh quantity obtained by the method in this paper is significantly less than ANSYS software.(3)The Heat-transfer basic equation,steady-state thermal-mechanical coupling equation and transient thermal-mechanical coupling equation of complex structural component and its Finite element numerical solutions are studied.The meshing model was used as the calculation input,for the steady-state thermal-mechanical coupling process,based on the unidirectional coupling relationship,the weak coupling analysis method was used to decouple the temperature field and the displacement field respectively and calculate the change law of the temperature field and the displacement field.For the transient thermal-mechanical coupling process,based on the bidirectional coupling relationship,the close-coupling analysis method is adopted to solve the temperature field and displacement field alternately and iteratively in the time domain,and the heat transfer law of the temperature field and the dynamic response characteristics of the displacement field are obtained.The results show that the steady-state thermal-mechanical coupling will lead to the thermal expansion of the structure.The transient thermal-mechanical coupling will induce the structure's vibration,and then the amplitude decreases gradually and finally becomes stable.