Learning Forum

[Stathis Stratakos]

Hi everyone,

I am trying to simulate a rotating structure constrained by magnetic bearings.

I have seen that in rotordynamics simulations I can create bearings setting stiffness and or damping values.

Should I use this approach even with magnetic bearings or could this be an oversimplification of the problem and lead to unreliable results?

Thank you!

Stathis

 

[peteroznewman]

Linear springs are used in the Bearing support used in rotodynamic simulations. Magnetic bearings have a nonlinear force-displacement curve, so in a large deflection transient analysis, the results would be different if you used linear springs. However for small deflections, the magnetic bearing operates over a small range that can be linearized without being oversimplified.

[Stathis Stratakos]

Dear Mr. Newman,

Thank you so much for taking the time to respond!

To achieve a higher reliability, should I run a simulation coupling the electromagnetic module with the mechanical one?

Best,
Stathis

[peteroznewman]

It depends on whether the disturbance forces acting at the bearing are large enough to get into the nonlinear range of travel. You have to decide that. It is possible to characterized the nonlinear force-deflection curve of the magnetic bearing in a module like Maxwell. There is a Magnetostatic module in Mechancial, but I am not familiar with using that.

[Stathis Stratakos]

Once more, thank you for your quick response and valuable suggestions!