Coupled reaction diffusion equations

Hello,
I am still quite newbie and I am trying to implement a reaction diffusion model which writes:

\partial_t u=D_u\nabla^2 u +u-u^3-v+k
\tau\partial_t v=D_v\nabla^2 v +u-v

where I have to unknowns : u and v. I roughly know how to write a weak formulation for the diffusion of a single species, but I am quite lost on how to proceed for two species, with coupled PDE and how to implement that in freefem. Would anyone have recommendations on that topic ?

Have a great day,

Marc

Hi,

See one of the examples for Navier-Stokes. Remove continuity/pressure and change the terms to match what is shown in your equations.

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Hi Chris,

Thanks a lot for your indication - I am going to see what I can make out of it, based on my rather low level in math and freefem :wink: - don’t ask me why I have to teach something I don’t understand well myself…

Hi! I’m also trying to solve these kind equations, have you solved your problem now? :stuck_out_tongue_winking_eye:

If you want to learn in 1D, I have examples in FF and c++ that are rather simplistic
and just meant to test mjmdatascope but for the right parameters you should be
able to run these indepedent codes and get similar plots. I don’t remember
but IIRC its backward Euler in c++ and maybe forward in FF fwiw.

mjmdatascope

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