Boundary conditions in a 2D RZ simulation

[alexnovoselov]

Hello,

I'm interested in running a 2D RZ coordinate simulation where the boundary conditions are R_hi = Inflow/Outflow, Z_lo/Z_hi = Periodic. From my understanding, the remaining boundary condition R_lo (the centerline of the cylinder) is required to be "Symmetry" when running in RZ. However, I'm interested in having this boundary condition act as a source/sink instead, which doesn't appear to be built-in functionality. Two approaches I've (only briefly) considered are 1) adding a source term to the points right next to the R_lo boundary or 2) digging into the Symmetry requirement to ultimately remove it and implement Inflow/Outflow for the R_lo boundary. I'd appreciate any insight from anyone who is more familiar with the code or has given this some thought. Is either method preferred? Is there a better method? Is this perhaps already possible?

Thanks!