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Solve 1D advection-diffusion-reaction equation

Hi,

I`m trying to solve the 1D advection-diffusion-reaction equation dc/dt+u*dc/dx=D*dc2/dx2-kC using Fortan code but I`m still facing some issues. first I solved the advection-diffusion equation without including the source term (reaction) and it works fine. but when including the source term (decay of substence with the fisr order decay -kC)I could not get a correct solution. I have read that I need to use the spliting time mthod or as called also the operator time method, but I do not know how to apply it.
Could any one help to provide a simple code for solving this advection-diffusion-reaction equation ? I would appriciate your help.

Regards, 0 9/20/2014 2:08:22 AM  comp.soft-sys.matlab  211266 articles. 23 followers. 3 Replies 1062 Views Similar Articles

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> Hi,
>
> I`m trying to solve the 1D advection-diffusion-reaction equation dc/dt+u*dc/dx=D*dc2/dx2-kC using Fortan code but I`m still facing some issues. first I solved the advection-diffusion equation without including the source term (reaction) and it works fine. but when including the source term (decay of substence with the fisr order decay -kC)I could not get a correct solution. I have read that I need to use the spliting time mthod or as called also the operator time method, but I do not know how to apply it.
> Could any one help to provide a simple code for solving this advection-diffusion-reaction equation ? I would appriciate your help.

Try to implement this term kC in time-implicit scheme; i.e. put it in t_(n+1) when solving in (t_n , t_(n+1) ). This scheme is more stable.

Bruno 0  Bruno
9/20/2014 7:00:14 AM
You might try to use time-implicit scheme for this term, which is stable and void numerical oscillation. 0  Bruno
9/20/2014 7:53:05 AM
> Hi,
>
> I`m trying to solve the 1D advection-diffusion-reaction equation dc/dt+u*dc/dx=D*dc2/dx2-kC using Fortan code but I`m still facing some issues. first I solved the advection-diffusion equation without including the source term (reaction) and it works fine. but when including the source term (decay of substence with the fisr order decay -kC)I could not get a correct solution. I have read that I need to use the spliting time mthod or as called also the operator time method, but I do not know how to apply it.
> Could any one help to provide a simple code for solving this advection-diffusion-reaction equation ? I would appriciate your help.
>
> Regards,
>
>

Try MATLAB's "pdepe" (at least to check your results) - it uses an implicit method for time integration.

Best wishes
Torsten. 0  Torsten
9/22/2014 12:45:08 PM Similar Artilces:

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