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Matrix has zero on diagonal - Calculating inductance using AC/DC module

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Hello All,

I'm totally new to the AC/DC module and in Electromagnetism, in general, and I would like to start learning it by building a simple example (see attachment). I have built it by following the "Inductor 3D" model, but I can't manage to make it work. When I run the model it gives:

"Failed to find a solution.
Matrix has zero on diagonal"

I assume that has something to do with the Boundary Conditions, but which ones? Can anyone help me with it? Thanks!


2 Replies Last Post 2017年6月6日 GMT-4 04:30

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Posted: 7 years ago 2017年6月6日 GMT-4 00:04
Updated: 7 years ago 2017年6月6日 GMT-4 00:05
Paul,

When you click on the link provided in the error message, you will be referred to the comsol website saying that:

"... it is not possible to use the following linear system solvers/preconditioners/smoothers: all versions of SOR and Jacobi (diagonal scaling). Try the Vanka preconditioner/smoother instead."

To solve this, go to the solver, right click on "iterative 1" and select "vanka".

Run the simulation. It will work.

Amin,
Paul, When you click on the link provided in the error message, you will be referred to the comsol website saying that: "... it is not possible to use the following linear system solvers/preconditioners/smoothers: all versions of SOR and Jacobi (diagonal scaling). Try the Vanka preconditioner/smoother instead." To solve this, go to the solver, right click on "iterative 1" and select "vanka". Run the simulation. It will work. Amin,

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Posted: 7 years ago 2017年6月6日 GMT-4 04:30
Thank you, Amin! That worked. You are a life savior :-)
Thank you, Amin! That worked. You are a life savior :-)

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