Moving Mesh Simulation – Fatal Error During Assembly/Calculation

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Dear colleagues,

I would like to seek your advice on a moving mesh simulation issue.

Current Model: I am simulating "the motion of a current-carrying conductor rod under the influence of a coil's magnetic field."

Physics Interfaces Used: Moving Mesh Magnetic Fields (AC/DC Module) Global ODEs and DAEs (for equation-based modeling)

Implementation Details: In the Magnetic Fields interface, I added a Force Calculation condition to compute the electromagnetic (Lorentz) force. The calculated force is passed to a global differential equation: F=ma=mxtt The displacement is then fed into the Moving Mesh interface to update the conductor rod's position. Since the electromagnetic force changes as the rod moves, I use Transient Analysis in the study step.

Issue: Despite multiple adjustments, the simulation consistently fails with the error: "A fatal error occurred during assembly or calculation."

Request: Has anyone encountered similar issues or have suggestions for troubleshooting? Any insights on: Correct coupling between Magnetic Fields, ODE, and Moving Mesh? Solver settings for such coupled electromechanical problems? Common pitfalls in force-driven moving mesh simulations? Thank you in advance for your expertise! Best regards,

Liu



1 Reply Last Post Jun 20, 2025, 10:52 a.m. EDT

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Posted: 18 hours ago Jun 20, 2025, 10:52 a.m. EDT

Hi,

If you can, please share your .mph file.

Hi, If you can, please share your .mph file.

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