Modeling of a cantilever beam surrounded by air with the application of an initial deformation and an electrostatic force

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Hello, I’m a beginner with COMSOL, and I’m trying to model a cantilever beam in the MEMS module, applying an initial deformation and an electrostatic force. For the initial deformation, I tried imposing either an initial stress and strain or a prescribed displacement in the Solid Mechanics physics, and I managed to achieve the deformation I wanted. For the electrostatic force, I applied a voltage using the Terminal option on the beam and grounded the air block below the beam. Finally, I added the Moving Mesh physics with the Deforming Domain option on the air to make it move according to the beam.

Unfortunately, when I run the simulation, I encounter the following error that I am unable to resolve: - Feature: Stationary Solver 1 (sol1/s1) Undefined value found. - Detail: Undefined value found in the equation residual vector. There are 921 degrees of freedom giving NaN/Inf in the vector for the variable comp1.spatial.u. at coordinates: (0.000231,2e-05,4.8e-06), (0.0002345,2e-05,4.8e-06), (0.000238,2e-05,4.8e-06), (0.000231,2e-05,6.1875e-06), (0.000231,2e-05,7.575e-06), ...

There are 921 degrees of freedom giving NaN/Inf in the vector for the variable comp1.spatial.v. at coordinates: (0.000231,2e-05,4.8e-06), (0.0002345,2e-05,4.8e-06), (0.000238,2e-05,4.8e-06), (0.000231,2e-05,6.1875e-06), (0.000231,2e-05,7.575e-06), ...

There are 921 degrees of freedom giving NaN/Inf in the vector for the variable comp1.spatial.w. at coordinates: (0.000231,2e-05,4.8e-06), (0.0002345,2e-05,4.8e-06), (0.000238,2e-05,4.8e-06), (0.000231,2e-05,6.1875e-06), (0.000231,2e-05,7.575e-06), ...

I noticed that by significantly reducing the initial deformation, the model works, but I don’t know why.

Do you have any ideas on how I could solve this? Thank you in advance


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