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Extrusion Coupling in 4.1
Posted Apr 20, 2011, 6:23 p.m. EDT Fluid & Heat, Chemical Reaction Engineering, Geometry, Modeling Tools & Definitions, Parameters, Variables, & Functions Version 4.1 4 Replies
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The documentation (Multiphysics User's Guide) only demonstrates how to set up an extrusion, but I don't see how to actually create variables to use it.
Here's a very simple problem I'd like to start with:
I have a rectangular 2D domain. I have laminar flow (spf) and transport of diluted species (chds) for the physics. I have two species: A and B. I want an equilibrium surface reaction on the top and bottom boundaries of this domain such that K = C/(A*B) is always satisfied on the boundaries and C is a surface concentration that is immobile and only changes due to be at equilibrium (K =C/(A*B)) with the two species A and B at the boundary.
It seems to me like I need to create a 1-D geometry with the same length as the 2-D rectangle. Then, I want to couple these so that the concentrations of A and B from the 2D model on the boundaries define C in the 1-D domain, and the concentration of C in the 1-D domain define the concentrations of A and B along the top/bottom boundaries in the 2-D domain (defined by the equilibrium equation).
Please help if you can. Thanks!
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in V4 you create "operators" under the "Definitions" node, then you call the operator in a variable declaration or in an equation. i.e once defined the "linext1" operator you may use it as "linext1(u)" or with whatever variable that fits.
This applies also to the integration (coupling variables) operators
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Good luck
Ivar
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You can also use weak form for the species reactions on boundaries of the reactor wall and then couple the outgoing product concentrations with the bulk flow of the reactor channel.
Mayur
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Your idea sounds promising, but I am not familiar with the weak form that you speak of. Could you provide some more information about what this is and how it is implemented in V4.1?
Thanks,
David
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