This documentation gathers all questions you may have on how to carry elementary tasks with MANATEE software dedicated to e-motor vibroacoustic simulation, e.g. how to identify the root cause of e-NVH or how to implement noise control actions. They are sorted following e-NVH simulation chronology, starting with the electrical machine definition, ending with simulation result interpretations.
You can browse these questions in two ways:
using the search engine on top right corner of EOMYS website, starting you question with “How to…” start with the first one|How MANATEE files are organized and clicking Next at the bottom of the page to read all the questions thoroughly using the following tree view to find a specific question based on keywords
If you can’t find the answer to one of your question, you can drop us an email at manatee(toremove)eomys.com.
Definition In Manatee software, the electromagnetic excitations due to Maxwell forces are linearly decomposed into Load Cases. To do so, magnetic excitations are generally expanded in Fourier series along the airgap (for Maxwell stress) or along tooth distribution, resulting in a certain number of wavenumbers.… Read More »What is a magnetic Load Case (LC)?
Definition Given the normal vibration velocity of an elementary surface, it is possible to evaluate the acoustic power with the following relation: begin{equation*}W= frac{1}{2} rho_0 c v^2 S sigma_r end{equation} where: is the overall acoustic power [W] radiated by the system under study (e.g. an… Read More »What is Equivalent Radiated Power (ERP)?
The airgap flux distribution (radial & tangential components in the middle of the airgap as a function of time and space) can be imported from third party electromagnetic software to Manatee software in order to carry electromagnetic noise and vibration analysis. The following tutorial explains… Read More »How to get the airgap flux distribution from Altair Flux?
Manatee software does not include models for the assessment of aerodynamic noise and vibrations (e.g. fan noise), neither for mechanical noise and vibrations (e.g. bearing, gearbox). Fan whine, gear whine and e-motor whine are three different physical problems that require specific numerical solvers and specific… Read More »Can Manatee calculate aerodynamic and mechanical noise (e.g. gear whine)?
Manatee V2 default models assume a weak coupling between electromagnetic and structural models. The weak coupling is valid when rotor and stator radial displacements are much smaller than the effective airgap width, which is generally the case, especially for surface PM machines. As an example,… Read More »Can Manatee model a strong magneto-mechanical coupling?
In theory, acoustic noise and vibrations due to electromagnetic forces in electrical machines involve two sources of magnetics forces: Maxwell forces, mainly concentrated at the interface between iron and air, and magnetostrictive forces, occuring in the lamination material itself. Manatee V2 software only accounts for… Read More »Can Manatee calculate magnetostriction effects?
Manatee vibroacoustic models can be coupled to any third party 2.5D electromagnetic software (Opera, Jmag, Flux, Magnet, Maxwell , Femag etc.) by importing the airgap flux distribution in Manatee as a .csv sheet. This import can be done include skew and variable speed operation. If… Read More »Can Manatee be coupled to JMAG / FLUX / OPERA / MAXWELL / MAGNET / …?
Objectives The accurate calculation of noise and vibrations induced by e-machine operation requires the assessment of vibro-acoustics at variable speed, taking a high number of speed steps to correctly catch structural resonances (the less damping, the more speed steps). This can represent a high computational… Read More »What is Load Extrapolation Algorithm (LEA)?
Manatee® is a complementary software service that helps you getting the best out of your current CAE software to efficiently solve magnetic noise and vibration problems. Manatee® is not designed to replace electromagnetic, structural mechanics or acoustics FEA software. This is why all Manatee® customers… Read More »What is the difference between Manatee and multiphysic numerical software suites (e.g. Ansys Workbench, Comsol Multiphysics, Siemens Simcenter)?
The airgap flux distribution (radial & tangential components in the middle of the airgap as a function of time and space) can be imported from third party electromagnetic software to Manatee software in order to carry electromagnetic noise and vibration analysis. In this article is… Read More »How to get the airgap flux distribution from Ansys Maxwell?
Principle The EVS (Electromagnetic Vibration Synthesis) is a proprietary algorithm of Manatee designed to speed up electromagnetic noise and vibration calculation while giving more physical insights on the e-NVH behaviour of an electrical system. It consists in decoupling the vibrational characterization of the electric motor… Read More »What is Electromagnetic Vibration Synthesis (EVS) algorithm?
Introduction Manatee e-NVH CAE collaborative platform has been initially developed by EOMYS to support its consulting activities aiming at troubleshooting and solving on electric machine noise problems. Manatee has therefore been successfully applied to predict and mitigate noise and vibration due to magnetic forces on… Read More »How to improve e-NVH test & simulation correlation?
