This key feature of Manatee software allows to import the modal basis of a third party 3D FEA mechanical software.
Manatee includes its own modal expansion algorithm which has been optimized for noise and vibration calculation under electromagnetic forces. During the modal basis import, Manatee also performs pre-calculations to speed up e-NVH simulation.
The associated mesh should include the definition of some key node sets : lumped magnetic load vector application nodes on stator (in the middle of tooth tips), and enveloppe nodes for the calculation of air-borne noise level. Optionally, the user can define magnetic force application nodes on rotor side (e.g. to include UMP on an internal rotor), and nodes for vibration-only calculations.
Modal basis import can be used by mechanical engineers in detailed design phase, once the electrical machine environment is known (e.g. casing geometry). Ideally, the 3D FEA mechanical should have been fit with experiments (e.g. EMA on a first prototype) in order to use a realistic modal basis. The use of the modal basis coming from a 3D FEA mechanical model improves the absolute accuracy of Manatee results, and allows to identify the contribution of each mode to the sound power level.