|
[Sponsors] |
![]() |
![]() |
#1 |
Senior Member
Join Date: Dec 2019
Posts: 215
Rep Power: 7 ![]() |
Hi,
I am using the kOmegaSSTDES turbulence model with rhoCentralFoam. I am questioning my boundary conditios for k, nut and omega. Since my mesh is coarse near walls, I am using wall functions: k: type kqRWallFunction; value 1e-10; omega: type omegaWallFunction; value 1e2; nut: type nutkWallFunction; value uniform 0; Still, nut and k become quite large near walls and are nowhere close to 0, like it should actually be atleast for nut, since the kqRWallFunction is basically a zeroGradient BC. Nut is always bigger than nu. I have read in a paper (http://www.tfd.chalmers.se/~hani/kur...DES-Report.pdf) that they have used a fine grid near the wall (y+ below 11) and used fixedValue with (1e-10) k and nut (0). This was for openfoam2.x.x. Actually I am modeling supersonic jet steam and I am interested in the shear layer of the jet. The walls are actually not of interest, but I have to apply the right boundary conditions to them. So my question is are wall functions implemented in the DES model and why do I get those large values for k and nut at the walls? Last edited by shock77; November 4, 2020 at 10:13. |
|
![]() |
![]() |
![]() |
|
|
![]() |
||||
Thread | Thread Starter | Forum | Replies | Last Post |
Centrifugal fan-reverse flow in outlet lesds to a mass in flow field | xiexing | CFX | 3 | March 29, 2017 10:00 |
Wrong flow in ratating domain problem | Sanyo | CFX | 17 | August 15, 2015 06:20 |
Waterwheel shaped turbine inside a pipe simulation problem | mshahed91 | CFX | 3 | January 10, 2015 11:19 |
Question about heat transfer coefficient setting for CFX | Anna Tian | CFX | 1 | June 16, 2013 06:28 |
Low Mixing time Problem | Mavier | CFX | 5 | April 29, 2013 00:00 |