Spectral-element method for high-speed rotating cylinders
Purpose - The purpose of this paper is to offer a fast and reliable discretisation scheme for computing the electromagnetic fields inside a ferromagnetic cylinder, accounting for motional eddy currents under high velocities and accounting for the severe ferromagnetic saturation of the rotor surface. Design/methodology/approach - A nonlinear spectral-element (SE) formulation is developed and compared to existing analytical and finite-element approaches. Findings - The proposed SE method results in a higher accuracy, allows for smaller models, avoids upwinding and needs less computation time. Disadvantages are the dense system matrix and the bad condition number. Research limitations/implications - The SE approach is only developed and tested for 2D models with a single cylindrical domain. Practical implications - The results of the paper may improve the design and optimisation of solid-rotor induction machines and magnetic bearings. Originality/value - The paper offers an appropriate solution for a computational problem, which already has been encountered, by a large community of researchers and engineers dealing with high-speed rotating devices.
electromagnetic fields eddy currents machine tools