[petsc-users] How to add a source term for PETSCFV ?

[Jed Brown]

How would you like to discretize the diffusive terms?  The example has a type of gradient reconstruction so you can have cellwise gradients, but there are many techniques for discretizing diffusive terms in FV.  It's simpler if you use an orthogonal grid, but I doubt that you are.

As for terminology, the diffusive part is usually stiff and thus must be treated implicitly.  In TS terminology, this would be part of the IFunction, not the RHSFunction.

Thibault Bridel-Bertomeu <thibault.bridelbertomeu at gmail.com> writes:

> Dear all,
>
> I have been studying ex11.c from ts/tutorials to understand how to solve an
> hyperbolic system of equations using PETSCFV. I first worked on the Euler
> equations for inviscid fluids and based on what ex11.c presents, I was able
> to add the right PETSc instructions in an already existing in-house code
> with different gas models  to solve the problems in parallel (MPI) and with
> the AMR capabilities offered by P4EST.
>
> Now my goal is to move to Navier-Stokes equations. Theoretically the system
> is not completely hyperbolic and can be seen as one with an hyperbolic part
> (identical to the Euler equations) and a parabolic part coming from the RHS
> diffusion terms.
> I have been looking into the manual and also the sources of PETSc around
> the DM, DMPlex, DS and FV classes but I could not find anything that speaks
> to me as "adding a RHS to an hyperbolic system of equations" or "adding a
> source term to an hyperbolic system of equations". What's more, that source
> term depends on the derivatives of the context variables ...
>
> I wanted to know if anyone maybe had a suggestion regarding this issue ?
>
> Thank you very much in advance,
>
> Thibault Bridel-Bertomeu
> —
> Eng, MSc, PhD
> Research Engineer
> CEA/CESTA
> 33114 LE BARP
> Tel.: (+33)557046924
> Mob.: (+33)611025322
> Mail: thibault.bridelbertomeu at gmail.com