How can I use the frozen permeability feature in Flux?

The “Frozen permeability” in Flux is a specific feature that allows freezing the permeability from a first computation. The frozen permeability can be used in a second computation with different values of current, or without magnet for instance.

To activate the frozen permeability, you have to follow the procedure below:

11 Solve the first case

Select Parameter/Quantity -> Export quantity-> Export spatial quantity and formula starting from different types of supports

Here is an example how to fill in the fields:

  • Support for exportation: Face region
  • Face region: Name of one region
  • Export format: DEX Flux file format
  • File Name : Name of the file *.DEX to be created
  • Formula: MurIncr (click on f() to open the formula editor, select µr inc and click on OK)

3Click on the OK button (normally a specific *.DEX file is created in the working directory)
4Close the current project
5Open the 2nd Flux project

Select Parameter/Quantity -> Import parameter and quantity -> New (constant) tabulated spatial quantity by importation

Here is an example how to fill in the fields:

  • Name of the tabulated…: FROZEN_MU_1
  • Support for importation: Surface region
  • Surface region: Name of one region
  • File name: *.DEX

7Click on the OK button

Create a new magnetic material (select Physics->Material->New)

  • Fill in the field Name of the material
  • Check the Magnetic property case
  • Select Spatial linear isotropic (close to the end of the list)
  • Select FROZEN_MU_1 in the Spatial relative permeability field
  • Click on the OK button
9Modify the property of one region in order to use this new material
Note: you have to repeat steps 8 and 9 for each region with frozen permeability
10Solve the 2nd project and analyze the results