Time-Dependent Solver doesn't progress from 0%

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Hi everyone,

I'm currently working on a 3D simulation (+Magnetic Fields (mf) interface) involving an oscillating object along the z-axis, surrounded by deforming air domains. The object motion is prescribed using a sin(2pift) deformation, also for the upper and lower "air slugs" with (I hope) the correct deformation functions. The simulation needs to be in 3D since I'm gonna add asymmetric coils to the geometry to simulate induction voltages in pickup coils.

I've added a stationary solver at the beginning, and producing a stationary magnetic field plot is fine. Everything also seems fine geometrically and mesh-wise, but my time-dependent solver fails immediately with the following error:

Failed to find consistent initial values.Singular matrix.For mesh case 0 there are 72 void equations (empty rows in matrix) for the variable comp1.mf.mag1.Vc_d0...

I correctly added all the magnetic insulations boundaries, continuity bound pairs and right now I am at a loss for solutions. I would be happy if someone with experience helped me out.

Best regards.



1 Reply Last Post Apr 23, 2025, 6:48 p.m. EDT

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Posted: 1 day ago Apr 23, 2025, 6:48 p.m. EDT
Updated: 1 day ago Apr 23, 2025, 6:55 p.m. EDT

In Stationary the Magnet has no dependent variable Vc_d0 (Electric potential (conductors)), but in time-dependent this dependent variable variable exists. I think it needs some boundary conditions or initial Value.

You could remove this dependent variable by setting in Magnet 1 the 'Constrain for induced currents' to 'No induced currents constrain'.

Nice greetings.

In Stationary the Magnet has no dependent variable Vc_d0 (Electric potential (conductors)), but in time-dependent this dependent variable variable exists. I think it needs some boundary conditions or initial Value. You could remove this dependent variable by setting in Magnet 1 the 'Constrain for induced currents' to 'No induced currents constrain'. Nice greetings.

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