[Saideep]

Hi Guys;

I have a question regarding the domain decomposition for running a case on parallel using MPI.

I used the simple decomposition until now and ran into no problems for simple cases.

I am trying to have a domain in the shape of a "T". Please see the attached figure (the colors indicate allocation of cells to processors using another software - Gerris). Within that domain, I would like to allocate the mentioned zone (marked by red solid boundary) to a specific processor.

Reason: When I inject fluid through two inlets, the main physics occurs at the junction point and I would like to allocate that region (junction) to 1 processor.

Now, from my understanding this can't be done using the simple, hierarchical or scotch decomposition. The one left is the "manual" decomposition.

From the users manual I see that we can assign specific cells to a specific processor. (can anyone direct me here for an example).
However, I have too many cells in that region where cherry picking and allocating each individual cell within that region is rather impossible.

Can anyone advice me here how to proceed please.

Thanks;
SaiD