I am trying to simulate water
 

I am trying to simulate water drop (of diameter D) in moving air. For this purpose, I would like to solve a flow field and introduce a liquid drop into the system.

I see that boxtoCell would create a box type patch..how can I create a spherical fluid patch. If my case is axisymmetric what should I use?

I also did see the rotatedboxtoCell but not sure if its the right thing to use.

HI： i am also interested in
 

HI：
i am also interested in the question.there are lots of branches in TopoSetValue.could anyone explain how to use these utilities

You'll have to create your own
 

You'll have to create your own code to generate and write out a faceSet (which can then be used to make a patch). (the faceSet application with the boxToFace, rotatedBoxToFace etc. sources just handles the most general cases)

faceSets are very easy to code, e.g.

// Generate faceSet called f0 with size 100
faceSet f0(mesh, "f0", 100);
// Add faces based on face centre
forAll(mesh.faceCentres(), faceI)
{
if (mesh.faceCentres()[faceI].x() < 0)
{
f0.insert(faceI);
}
}
// Write to file
f0.write();

hi Mattijs：thanks but i jus
 

hi Mattijs：thanks
but i just want to set a circul cylinder inside the hydrocylone which i want to patch a air-core,is there any basic sources ?how can i use them? thankS!