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Weird results after linking reaction-diffusion modules?
Posted May 26, 2012, 9:34 a.m. EDT Version 4.2 1 Reply
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Hi All
I'm trying to solve a big reaction diffusion problem so I've started with a small test...
The final model will have so many reactions in it that I want to use the reaction module to simplify specifying all the reactions. I then added a multiphysics link to a diffusion module to take care of the reactants diffusing when they are injected into the diffusion space from outside (actually its going to be a model of a biological cell). The code runs and the gradient of reactant seems reasonable at first (from edge to center) then 'lateral' gradients develop that should not appear in this test which should approach a uniform steady state as there is no injection at later times. It's also not clear that any of the reactions are working. I have no idea what is going wrong and I've run out of fiddling options as nothing seems to help. According to the documentation this should be possible ... any ideas? I attach the model below.
Cheers Mark
I'm trying to solve a big reaction diffusion problem so I've started with a small test...
The final model will have so many reactions in it that I want to use the reaction module to simplify specifying all the reactions. I then added a multiphysics link to a diffusion module to take care of the reactants diffusing when they are injected into the diffusion space from outside (actually its going to be a model of a biological cell). The code runs and the gradient of reactant seems reasonable at first (from edge to center) then 'lateral' gradients develop that should not appear in this test which should approach a uniform steady state as there is no injection at later times. It's also not clear that any of the reactions are working. I have no idea what is going wrong and I've run out of fiddling options as nothing seems to help. According to the documentation this should be possible ... any ideas? I attach the model below.
Cheers Mark
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1 Reply Last Post May 27, 2012, 3:51 a.m. EDT
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Posted:
1 decade ago
I fixed it by letting the multiphysics generate a new model for the diffusion rather than hand patch a diffusion module within the same model... I'm guessing that either I made a mistake in the linking variables or that the well stirred nature of the reaction module is messing up the gradients generated by the diffusion module...
Cheers
Cheers