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Diffusion in thin film

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Hello. I'm trying to simulate diffusion of CO2 molecules in a thin film polymer under certain pressure and temperature for a set time. However, I don't have the Chemical Engineering Module, but have the Fluid one. Is there a way I could simulate that? (Im running 5.3a)


1 Reply Last Post Jul 23, 2018, 6:02 a.m. EDT

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Posted: 6 years ago Jul 23, 2018, 6:02 a.m. EDT

Hi,

Your question is not very clear because you do not explain how you want to model it.

If you want to explicitly model diffusion through a thin film layer such as a tube in 3D or rectangular plate in 2D, then just use PDE form and invoke only those terms in the PDE that you need. This is very easy.

If you do not want to represent the thin film explicitly to avoid meshing difficulties, especially, if it is a part of a significantly larger domain (as in fractures), then you can once again use boundary PDEs and achieve the same.

The most important thing to remember is that you ensure that the governing equation you have at hand is correctly represented in the PDE form.

Suresh

Hi, Your question is not very clear because you do not explain how you want to model it. If you want to explicitly model diffusion through a thin film layer such as a tube in 3D or rectangular plate in 2D, then just use PDE form and invoke only those terms in the PDE that you need. This is very easy. If you do not want to represent the thin film explicitly to avoid meshing difficulties, especially, if it is a part of a significantly larger domain (as in fractures), then you can once again use boundary PDEs and achieve the same. The most important thing to remember is that you ensure that the governing equation you have at hand is correctly represented in the PDE form. Suresh

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