[agarwa58]

Hi all,

I am trying to model a simple problem of flow through a tunnel duct. The domain consists of a velocity inlet and 2 pressure outlets as shown in the image attached. The tunnel receives liquid flow at the inlet and fills up only the bottom half of the tunnel volume. The solution starts smoothly but crashes after few iterations (at t=5 sec).

Even after repeated attempts and different combination of numerical schemes & BCs, I couldn't prevent the solution from crashing. The mesh quality looks good with no errors reported on running checkMesh.

Can someone inspect the case files and check if the BCs are defined correctly? Also, are the fvSchemes and fvSolution files ok for a robust multiphase simulation run? All the relevant files are attached here. It will be great if someone can help out ASAP.

Thanks and Regards,
Pulkit

[katete]

Hey,

I am also using interFoam to simulate flow in closed ducts.
Here you can find a thread I started with a working set of boundary conditions for OF 2.4.0:
http://www.cfd-online.com/Forums/ope...behaviour.html


I had a look at your case and found the following:
- alpha.water: you might try inletOutlet at the inlet for water and air (see my case).
- p_rgh: are you using OF 2.3.0? As far as I know the buoyantPressure-bc is not supported anymore. Try fixedFluxPressure instead (https://github.com/NREL/SOWFA/issues/3).
- U: sometimes you can get stability problems when you are using fixedValue U for a three-dimensional geometry surrounded by walls. Try flowRateInletVelocity instead.

I hope this helps.

Kind regards
Katharina