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Switching between two boundary conditions

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Hello,

I've got a transport of diluted species model in which a transient flux condition is set before being set to 0.

I wish to make it so that at the time the influx stops, the flux condition get's overridden by an open boundary condition.

Is there any way to change what boundary conditions override eachother with time? Or alrernatively, to model a flux boundary condition to behave similarly to an open boundary condition?


2 Replies Last Post 2 nov 2021, 12:59 GMT-4
Henrik Sönnerlind COMSOL Employee

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Posted: 3 years ago 2 nov 2021, 07:00 GMT-4

Maybe you can find some inspiration here:

https://www.comsol.com/blogs/how-to-make-boundary-conditions-conditional-in-your-simulation

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Henrik Sönnerlind
COMSOL
Maybe you can find some inspiration here:

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Posted: 3 years ago 2 nov 2021, 12:59 GMT-4
Updated: 3 years ago 2 nov 2021, 13:00 GMT-4

Maybe you can find some inspiration here:

Hi,

Thank you very much for your response. Unfortunately I have already taken a look at it multiple times before asking for help and my head is spinning.

I've spent an hour longer looking over it trying to gain the best understanding of the principles that I can. This will likely go down to more general knowledge of COMSOL as I am largely a beginner but I don't see how this can change what boundary conditions are overridden.

Could you elaborate on the key paragraphs/points in the article I should pay attention to?

I can see that one can disable and enable a boundary condition at certain points. I can also see that one can dynamically change how the boundary condition can change with respect to position along the selection. Are you suggesting that there is a way I can replicate an open boundary condition with a flux boundary condition?

>Maybe you can find some inspiration here: Hi, Thank you very much for your response. Unfortunately I have already taken a look at it multiple times before asking for help and my head is spinning. I've spent an hour longer looking over it trying to gain the best understanding of the principles that I can. This will likely go down to more general knowledge of COMSOL as I am largely a beginner but I don't see how this can change what boundary conditions are overridden. Could you elaborate on the key paragraphs/points in the article I should pay attention to? I can see that one can disable and enable a boundary condition at certain points. I can also see that one can dynamically change how the boundary condition can change with respect to position along the selection. Are you suggesting that there is a way I can replicate an open boundary condition with a flux boundary condition?

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