Edgar J. Kaiser
Certified Consultant
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Posted:
11 months ago
30 apr 2022, 10:22 GMT-4

In 2D axial you must use line integrals on the boundaries, because this is where the charge sits. You can check the surface integral checkbox to get integrated charge around the circumference of the respective edge.

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Edgar J. Kaiser

emPhys Physical Technology

www.emphys.com
In 2D axial you must use line integrals on the boundaries, because this is where the charge sits. You can check the surface integral checkbox to get integrated charge around the circumference of the respective edge.

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Posted:
11 months ago
1 mag 2022, 07:55 GMT-4

Thank you for your reply!
Yeah it is actually working only for ES Physics but the answer is very small (order 1e-20 F), I'm a bit skeptical of this result. When applying it to EC Physics, it is giving complex values for the line integration of the surface charge density, which is also unreasonable.

I am thinking that the capacitance in this case is a fixed value C = Q/U. i.e. for each potential applied to all parts of the conductor equally, the charges sitting on each surface will change in a way that keeps the ratio (Q/U) constant. are there any other methods for calculating the stray capacitance in comsol ?

Thank you for your reply!
Yeah it is actually working only for ES Physics but the answer is very small (order 1e-20 F), I'm a bit skeptical of this result. When applying it to EC Physics, it is giving complex values for the line integration of the surface charge density, which is also unreasonable.
I am thinking that the capacitance in this case is a fixed value C = Q/U. i.e. for each potential applied to all parts of the conductor equally, the charges sitting on each surface will change in a way that keeps the ratio (Q/U) constant. are there any other methods for calculating the stray capacitance in comsol ?

Edgar J. Kaiser
Certified Consultant
Please login with a confirmed email address before reporting spam

Posted:
11 months ago
1 mag 2022, 17:33 GMT-4

In order to verify your methods you may consider to use a simple model with an analytical solution. In 2D axial symmetry this could be a coaxial capacitor.

-------------------

Edgar J. Kaiser

emPhys Physical Technology

www.emphys.com
In order to verify your methods you may consider to use a simple model with an analytical solution. In 2D axial symmetry this could be a coaxial capacitor.