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Transport of Diluted Species, incorrect concentrations

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Hello everybody,

I have been trying to do the Comsol Micromixer tutorial which can be found under the following link:
www.comsol.com/model/download/215621/models.mph.micromixer.pdf

I succeeded in replicating all the flow patterns and graphs as in the tutorial.

Now my next step is to replace the existing structure with another structure. It is a tube with diameter .5mm, with a circular path three quarters of a circle of diameter 10mm.

With respect to the tutorial I changed the boundary conditions of the laminar flow. In the initial condition 1 I changed the velocity field to (0,0,0). And at the inlet I changed the velocity to U_mean and Normal inflow velocity. At the laminar flow discretization section I changed to P1+P1.

Now in the results of the simulation of the tube the concentration is not between 0 and 27 mol/m3, as expected and also shown in the results of the tutorial, but between 14 and 27 mol/m3.

Does anybody know what causes the outcome of the concentration profile to be wrong?


Regards,

Bas


0 Replies Last Post 14 oct. 2015, 01:06 UTC−4
COMSOL Moderator

Hello Mr Bas

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