Problem 45deg Inflow and Outflow
 

Hi guys

I want to investigate a flow over a cylinder with an velocitsy inflow angle of 45 degrees. Therfore I created the computational domain in the attachement. My inflow patch is the on the side in x-direction, outflow patch in following to that on the opposite. Top and Bottom of the domain are set to cyclic patches. Forget about the streamlines in the picture. The do make no sense.

Ok I am sure I have to use periodic boundary conditions. Tried also to implement them but always getting following error:

Here is the interesting part of my boundary file
and my U file respectively for p, eg...


What am I doing wrong?

no one can help me?

first thing first, how did you generate that mesh? It seems like your mesh cells on the top and bottom patches don't match up nicely, hence the complain from the solver. Typically, in order to use the cyclic boundary conditions, you need cell matching on the periodic BCs within certain tolerance (insert "matchTolerance 0.0001;" in your constant/polyMesh/boundary under the cyclic boundaries). For example,

patch1
{
type cyclic;
nFaces 100;
startFace 1;
matchTolerace 0.0001;
neighbourPatch patch2;
}
patch2
{
type cyclic;
nFaces 100;
startFace 101;
matchTolerace 0.0001;
neighbourPatch patch1;
}

If your cells in the top and bottom faces are way off, such that the matchTolerance parameter doesn't help, then you will have to use cyclicAMI instead of the cyclic boundary type. I know of it, but haven't used it myself, so can't help you with the details related to how to use cyclicAMI. However, I'm sure you can find some information on the forum by doing a quick search.

Hope this helps! good luck!

Hi, eRzBeNgEl!

I'm solving a flow around cylinder case with interFoam. My geometry is just like yours. I'm wondering how to simulate outflow BC(just like outflow BC in fluent) in openfoam.

I have tried freestream and freestreamPressure BC in U and p files. However, the drag coefficient doesn't match the values announced in papers.

Do you have any ideas?

thanks in advance.

I want to refresh this topic:

Now I tried to use cyclicAMI


This is what I did so far:
Made faceSets:
setSet
faceSet AMI new patchToFace sym1
faceSet AMI add patchToFace sym2
quit

setsToZones -noFlipMap


boundary file:

I also adjusted the initial conditions U and p correctly:

Now I got following error
:

I think I am almost there, the error is asking for intial target face. I thought I already defined this by faceSets at the beginning.