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Use of the previous study as initial condition for the next one

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Hi everybody, I'm trying to perform a time domain study starting from a previous one (using the latter as starting point). In order to do this I've found two possible solutions: 1) in the study settings under "initial values of variables solved for" and under "initial values of variables not solved for" set method-->solution and study--> the one to start from. 2) under the physics nodes (I have shell and pressure acoustics transient) set initial values --> the ones at the end of the previous study. However, I have problems with both solutions. With the 1) the problem is that the study correctly starts from the conditions at the end of the previous but then it evolves quite differently with respect to a study with a duration equal to the sum of the two (ex: one study from 0 to 1 sec vs two studies, one from 0 to 0.6 sec and one from 0.6 to 1). In fact if I compare the two solutions they are equal from 0 to 0.6 but then from 0.6 to 1 sec it seems there is a phase shift and a difference in amplitude. (See attached files) With 2) instead the problem is that I can only put a single value as "initial value" while in my physics I need the entire field of vibration, velocities and so on (so the values for each node of the mesh). I've also tried to do some sort of averaging over my domain to obtain a single value but it behaves in a strange way. Does anyone have a solution? Thank you for your attention,

Tommaso



0 Replies Last Post Nov 14, 2021, 8:44 a.m. EST
COMSOL Moderator

Hello Tommaso Botti

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