Introduction
Vibro-acoustic
Any electromagnetic device (linear actuator, electrical motor etc.) comprised of a metallic part in motion surrounded by air is susceptible to generate vibrations and noise.
The calculation of the noise is made by taking into consideration the electromagnetic phenomena that generate the motion of the device.
The vibrations and the noise can be troublesome for the device itself, but also for the environment. It is then necessary to take into account such phenomena, starting with the conception phase, by carrying out a study of sensitivity with vibro-acoustic parameters.
Static structural analysis
It is important for some devices to study mechanical constraints coming from magnetic forces. For example, in transformers, Laplace forces can represent a mechanical constraint on the winding. This aspect is to take into account when dimensioning the device.OptiStruct
OptiStruct is an Altair suite software which has the capabilities to make simulations in the two physical applications noticed above.
OptiStruct is integrated in the HyperMesh software interface. HyperMesh allows making the pre-processing (geometry and mesh) and defining also the OptiStruct simulation through the interface.
The export to OptiStruct is the most complete in terms of options and quality.
Solution brought by Flux
In order to offer the ability to carry out the computation of the acoustic noise, a dedicated context is integrated into Flux. It permits the user to cover all the stages up to the export of a file of magnetic forces , which will then be used with the software for the vibro-acoustic or mechanical study.
This context gives access to three types of computations, presented in the following table:
| Computation | Computation support | Computation method | Format of generated file | Associated software |
|---|---|---|---|---|
| Computation of surface magnetic forces on Flux mesh | Flux entities | Derivative of energy – Maxwell tensor (method used with Flux) |
.FEM .NAS .UNV .DAT |
.FEM .NAS .UNV .DAT |
| Computation of surface magnetic forces on rotating machine imported mesh | Mechanical meshing | Computation of the radial and tangent magnetic pressure in the airgap |
.FEM .NAS .BULK .DAT |
OptiStruct Nastran Femap |
| Computation of volume Laplace forces on Flux mesh | Flux entities | J^B |
.FEM .NAS .DAT |
OptiStruct |