can OpenFoam model a pole in Cylindrical mesh??
1 Attachment(s)
I am making a 3D cylindrical mesh for LES computations of premixed flames.
I would like to know if OpenFoam can correctly model singularities or poles at the origin (as shown in the attached figure) correctly, or would I have to mesh my geometry in a different manner. Would really appreciate any help on this topic. Thanks! |
I had previously tested this with rhoPimpleFoam, and did notice abnormal action along the cylinder axis (center of the "pie slices") where the cell skewness gets really large. I then tried rounding out one square hex, but this introduced abnormalities where the corners were stretched out (probably for the same reason). I then meshed a square in the center of the circle which simulated properly.
I honestly didn't spend too much effort trying to see if there were more advanced solver options to account for skewedness, I just changed the mesh. Somebody else with more experience may speak to your exact question. Good luck! |
I am wondering: why..? I mean, people use o-grids for this normally. I didn't really question this up to now, because I thought this is pretty common. Can you explain, why you prefer this way of meshing?
|
You are absolutely right, people use o-grids. It may have been my specific mesh/configuration/BC, but there were false temp/density iso's which protruded down the cylinder axis which should not have been the case. I was merely warning the OP that it is possible if he's not careful. As I said, I didn't play with it too much because it was simple enough for me to change the grid.
To keep an o-grid in my system I had calculated an excessively dense mesh in the center to keep the skewness down (increasing #/meter of "onion shells" around the axis where the "pie slice" tips narrow to zero @ the center). I have very little experience in CFD, but in my simulation, the denser mesh & running >3 nonOrthogonalCorrectors will slow me down, and I guessed a nice cubic in the center may help the solver converge more rapidly...? I wanted to spend the mesh density near the walls where there's something more interesting going on. Am I way off? |
Even I am modeling my mesh using an O-grid but was wondering if OpenFoam could model poles because for an axisymmetric grid it is able to take into account pole formation.
Anyways thanks for your reply Chris! :) |
3 Attachment(s)
Although it might be late for you, but I do have what you want.
You can change the length and radius from the .m4 file. Using the following command, you can get the blockMeshDict from the .m4 file. Code:
m4 circle.m4 > blockMeshDict |
All times are GMT -4. The time now is 02:29. |