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Two steps simulation

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Hi, I am trying to model a variable capacitor, composed of a bottom (fixed) electrode and a suspended bridge. At the first step, I used DC voltage to make the fixed-fixed bridge deflects a certain distance (done, with electromechanics module). Then at the second step, I want to use RF module to calculate s-parameters of the capacitor at the distance I simulated at step 1. My problem is I dont know how to tell the software to understand that I want to simulate the step 2 at the geometry after I have solved the step 1. Does anybody suggest me a way to deal with that. It is also good if you provide me with a link to a model in the library with similar situation that I can learn from. Thank you in advance.

2 Replies Last Post 31.03.2013, 12:09 GMT-4
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 28.03.2013, 02:58 GMT-4
Hi

you need to model the air (if you do not rely only on geoemtrical variables integration over gap distance and local areas) and this you do best with ALE so that the air deforms with the solid deformation, then you add a solver step only for the ES on the ALE air + electric part and you solve hence ina fully decoupled way => solid drived electromagnetics.
But you can solve all in one, need a bit more ram but it works nicely, you might then also inlcude electrostatic forces

--
Good luck
Ivar
Hi you need to model the air (if you do not rely only on geoemtrical variables integration over gap distance and local areas) and this you do best with ALE so that the air deforms with the solid deformation, then you add a solver step only for the ES on the ALE air + electric part and you solve hence ina fully decoupled way => solid drived electromagnetics. But you can solve all in one, need a bit more ram but it works nicely, you might then also inlcude electrostatic forces -- Good luck Ivar

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Posted: 1 decade ago 31.03.2013, 12:09 GMT-4
Thank you Ivar, I am trying :)
Thank you Ivar, I am trying :)

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