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Changing boundary condition - Matlab/Comsol

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Hi all,

I've got a problem where I'm trying to simply solve the diffusion equation with boundary conditions that change with time (one interval with a concentration imposed, followed by an interval with insulation bc).

I'm new to Comsol and Comsol with Matlab, but I was able to follow the manual on how to concatenate several transient solutions, but this is still very user intensive, similar to what I was doing before. I'd like to automate the process, and what I can't figure out is how to make the previous iteration's final solution the next iteration's initial condition...it seems like it should be possible.

I hope it's simple, but I'm new to Comsol and Comsol with Matlab so it's taking me some time.

I'm using v3.5a with R2009b. Thanks for any help.

3 Replies Last Post 08.06.2011, 04:27 GMT-4
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 09.05.2011, 14:50 GMT-4
Hi

you should define your BC value as a function of time, with smooth transition between the steps (use i.e. Heaviside functions)

--
Good luck
Ivar
Hi you should define your BC value as a function of time, with smooth transition between the steps (use i.e. Heaviside functions) -- Good luck Ivar

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Posted: 1 decade ago 08.06.2011, 04:27 GMT-4
hi,
i am studying about homogenisation problems and i am writing a code using matlab.
I want to use the incremental loading method, so the BC change in every step.
I defined BC in first step using pdetool, but i don't know how to defined these in the next step.

Could you help me?
hi, i am studying about homogenisation problems and i am writing a code using matlab. I want to use the incremental loading method, so the BC change in every step. I defined BC in first step using pdetool, but i don't know how to defined these in the next step. Could you help me?

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 08.06.2011, 04:27 GMT-4
hi,
i am studying about homogenisation problems and i am writing a code using matlab.
I want to use the incremental loading method, so the BC change in every step.
I defined BC in first step using pdetool, but i don't know how to defined these in the next step.

Could you help me?
hi, i am studying about homogenisation problems and i am writing a code using matlab. I want to use the incremental loading method, so the BC change in every step. I defined BC in first step using pdetool, but i don't know how to defined these in the next step. Could you help me?

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