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Magnetic Field in Time Dependent Study

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I want to move a conductor through a constant magnetic field of 1 T. How do I create this constant magnetic field?

My solution until now is an ampere law with remanent flux density. I then change the B_r for y until I get 1 T in the middle of my domain. It is not perfect, but it is a solution.

As long as I use a stationary study. When I use a time depentent study, which is of course what I need when I want to move the conductor, I get the following Error (translated from german): No consistent starting values found. Undefined value found. NaN or Inf at Solution of the linearized Equation System with BiCGStab. Last time step did not converge. - Feature: Timedependent Solver 1 (sol1/t1)

So, is there a better way to create a homogeneous magnetic field? Or if not, how can I make the amperes law work in a time dependent study?

https://www.dropbox.com/s/tr7gt3u3nxxhjay/10_27_MagFieldMovMeshError.mph?dl=0



1 Reply Last Post 27 ott 2022, 13:35 GMT-4
Edgar J. Kaiser Certified Consultant

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Posted: 2 years ago 27 ott 2022, 13:35 GMT-4

Hi Annika,

you have two (maybe more) options to create a uniform magnetic field:

  • Solve for the reduced field and enter the background field or vector potential. or
  • Apply a suitable vector potential to the outer boundaries of the modeling domain

For a time dependent study you would typically run a stationary study step before, to make sure the time dependent study starts with suitable initial values.

Cheers Edgar

-------------------
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
Hi Annika, you have two (maybe more) options to create a uniform magnetic field: - Solve for the reduced field and enter the background field or vector potential. or - Apply a suitable vector potential to the outer boundaries of the modeling domain For a time dependent study you would typically run a stationary study step before, to make sure the time dependent study starts with suitable initial values. Cheers Edgar

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