Computation of the noise radiation of an induction machine using 3D FEM/BEM

Purpose - The purpose of this paper is to set up a comprehensive numerical approach to estimate the 3D structural vibration and noise radiation of an induction machine. Design/methodology/approach - The rotating force waves, acting in the air gap of an induction machine and obtained by an electromagnetic finite element multi-slice simulation, are applied to the 3D structural finite element model and a structural harmonic simulation is performed. The sound emission due to the vibration of the surface of the machine is computed with a 3D boundary element model. Findings - The paper outlays problematic issues when setting up the numerical models, i.e. the structural finite element model. The material properties strongly affect the structural behaviour and therefore the radiated noise. Originality/value - The 3D force distribution in the air gap and the resulting vibrations are computed. The structural behaviour, i.e. the different vibrational behaviour of stator and surface is discussed. The correlation of the structural vibrations and the noise radiation is investigated.