[askjak]

I have a cylindrical geometry (see graphics) and I want to evaluate the angular momentum flux into the cylinder through the 30 ports (among other quantities) using a cylindrical coordinate system. The mesh is conforming between the two zones (red and blue).

My first attempt was to create a cyclic patch in each of the 30 ports and write a postprocessing tool based on patchIntegrate to find the angular momentum flux. This worked well formally, but it is very tedious to create the meshes in a commercial mesher in such a way that I can create the cyclic patches with createPatch (and we need a LOT of meshes). Other issues with this method is handling parallel postprocessing (see http://www.cfd-online.com/Forums/ope...-problems.html), and fundamentally I would prefer to get the angular momentum flux out during the simulation and not “postmortem”.

I have now created a faceZone for each of the 30 ports (see pink on graphics) according to the advice given in http://www.cfd-online.com/Forums/ope...-problems.html. I can now use OpenFOAM-1.6.x/src/postProcessing/functionObjects/field to get information out on a faceZone. But as I understand my problem is slightly more complex than the functionality in fieldValues since I need to know the position of the individual face and multiply phi with U before integration etc.

My question now is the following: What would you recommend? In some way extending the functionObjects?

+Ask

[lfbarcelo]

How did you create the faceZones?? I have made a mesh using snappyHexMesh. I meshed an stl corresponding to a surface with no width, inside a wind Tunnel. The problem is that paraView, in an attempt to show surface pressure, shows this surface as if it was "stained" because the pressure is different on each side of this surface. In order to "create" a certain width, ando solve this problem, I am trying to use "create Baffles", but I can't create the faceZone out of the patch, a face zone is necessary as an input agument for "createBaffles".