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Boundary Element Parallel Plate (ElectroMechanical Module)

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Hello, I am modeling a 2D Parallel plate capacitor using Boundary Element Method (BEM) and comparing its results with 2D FEM results and Analytical Formulation for the tip deflection of the moving electrode and the electrostatic forces.

When the depth is considered as 1(m), the results for all three different approaches (Analytical, FEM, and BEM) are almost the same (deflection=1.40E-07).

This deflection is not dependent on the depth of the structure. But when I change the depth to 100 [um], the deflection for Boundary Element Method (BEM) decreases astronomically to -9.50E-16, however, the Analytical and FEM results stay the same.

I have attached these two models here. Please let me know if I am considering something wrong.



1 Reply Last Post Nov 18, 2022, 12:00 p.m. EST
Acculution ApS Certified Consultant

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Posted: 2 years ago Nov 18, 2022, 12:00 p.m. EST

For acoustic BEM, I would point you to the 'Thin body problem', since you have singularity issues with the Green's functions for very small distances between adjacent elements and/or observation points. Could be the same for your case.

-------------------
René Christensen, PhD
Acculution ApS
www.acculution.com
info@acculution.com
For acoustic BEM, I would point you to the 'Thin body problem', since you have singularity issues with the Green's functions for very small distances between adjacent elements and/or observation points. Could be the same for your case.

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