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Reaction rate

Michael Rembe Certified Consultant

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Hello,

in a porous media transport problem I defined a simple reaction rate:
mc=k*(cs-c) (cs - saturated concentration).

This reaction rate also removes mass at locations with c>cs by numerical overshots.

Using a step function and a reactions rate mc=k*(cs-c)*step(cs-c) helps and converges, but it leads to c>cs at location with mc*timestep > max. mass in a mesh volume considered by cs.

I look for a limitation of mc, that considers the timestep in such a way that the resulting c <= cs.

Is there any good idea? Thanks a lot!!

Best regards
Michael Rembe

0 Replies Last Post Jul 13, 2017, 5:39 a.m. EDT
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Hello Michael Rembe

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