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Using solution from electrostatic solver for transient EW solver

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As the topic states, I'm having an issue using the solution from a stationary electrostatic solution as the initial condition for a transient EM wave solver.

What I'm aiming to do is solve for the field of a charged coaxial structure and then model the reflections in the transmission line if one of the ends is shorted. For the test case I'm using a simple coaxial geometry which should produce a sine wave inside the lossless cable with a wavelength 4 times the length of the line.

In this test case I'm using the geometry from the "Transient Model of a Coaxial Cable" example (1mm center conductor, 1mm air gap, 40 mm long). I set up ES physics with a voltage of 1 on the inner conductor and ground on the outer. The transient model is setup with an open at one end of the line (PMC) and a short at the other (PEC).

The stationary solver finds the electric field but the issue I'm having is figuring out how to set this solution as the initial condition for the time dependent solver. To date, I've tried with 2 steps in a single study and as separate studies. Currently, I have the first solution from solver 1 being saved and the second solver setup to use the solution as the initial condition. I think the issue is that the ES solver does not solve for the magnetic vector potential which is used to by the transient solver. Anyone have an idea how something like this could be done?


0 Replies Last Post Jul 9, 2012, 9:36 p.m. EDT
COMSOL Moderator

Hello Jordan Chaparro

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