The 3-D computations of edge induction heating using semi-analytical method and FEM

Contents

Both a 3-D semi-analytical method and an approach based on a 3-D FEM are presented to calculate the electromagnetic and thermal fields for edge induction heating. The proposed semi-analytical method is based on the separation of variables and the discrete Fourier transform to solve the eddy current problem. The Fourier components are sinusoidal functions with complex arguments. Boundary conditions are used to determine the unknown coefficients, and a criterion for the existence of the solution is given. The thermal problem is solved by a nonlinear FEM by considering the radiation boundary condition. The computation results show that after the edge induction heating the temperature at the edges of the steel bar is really raised as expected to compensate the temperature drop at the edges during the steel strip casting process. Compared with experimental model records, the proposed algorithms are verified. Comparisons performed include the distribution of temperature and four main characteristic quantities of the edge induction heating. The error observed is less than 15%. Because the computation shows the distributions of the power and fields in the heated bar, it can be expected to achieve an optimal design for the edge induction heating.