How can I compute normal and tangential forces on a region in Flux?


The magnetic force computation in Flux is based on the virtual works method; it assumes that the region on which the force is computed is surrounded by air.

In order to compute the magnetic force (normal and tangential components) on a region, one should follow the steps below:

1In menu Advanced click on Sensor -> New
2

Select the type Predefined (Energy, Force, Torque,..) and select the region
e.g. Magnet region in rotating machine. Note that the region is surrounded by air

3

Evaluate the sensor

Note: you can create the sensor before the solving in order to evaluate it during the solving process

4Display sensors curves
5

Export the curves and compute the normal and tangential components in Excel for instance (you can also ask an example to the support)

Note: The normal and tangential components are computed using the rotation matrix:
Fr= Fx *Cos(θ) + Fy * Sin(θ)
F θ= -Fx *Sin(θ) + Fy * Cos(θ)