CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > OpenFOAM > OpenFOAM Running, Solving & CFD

simpleFoam kOmegaSSt boundary conditions

Register Blogs Members List Search Today's Posts Mark Forums Read

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   April 1, 2022, 06:14
Default simpleFoam kOmegaSSt boundary conditions
  #1
New Member
 
Sean
Join Date: Apr 2022
Posts: 5
Rep Power: 4
DataDriven is on a distinguished road
Hi everyone,

I’m a long time visitor and lurker on the forum. Today I’m making my first post! Thank you in advance

I’m struggling to get a simpleFoam kOmegaSST turbulence model to run on OF7.

The cases existed in the department, though I had to make two changes to get simpleFoam to run:
  • in constant/fvOptions > momentumsource I changed “fieldNames” to “fields” (this tells that the case used to run on a different version of OF?)
  • in 0/nut the walls had “calculated” which gave errors so I changed it to “nutLowReWallFunction”.
The initial conditions are read in properly, but when running simpleFoam the solution is not right. Please see the attached image of the velocity field on the 0th, 100th and 500th iteration. Judging from the field I suspect something is wrong with BC on either the inlet or walls.

I have a working case of kOmegaSST which has largely the same BC, although in that case the inlet and outlet are cyclic so I cannot compare the inlet and outlet. I have tried many different values, settings and wall functions but the results remains wrong. Can anybody help me spot the issue?

Due to the interpolated values the files are too large to attach, please see a summary of the 0 directory below. If anyone requires more information or files please let me know!

U:
internalField --- nonuniform List (interpolated LES data)
inlet ------------ fixedValue nonuniform List (… fully developed channel flow)
topWall --------- fixedValue uniform(0 0 0)
bottomWall----- fixedValue uniform(0 0 0)
outlet ---------- zeroGradient

p:
internalField --- nonuniform List (interpolated LES data)
inlet ------------ zeroGradient
topWall --------- zeroGradient
bottomWall----- zeroGradient
outlet ---------- fixedValue uniform(0)

nut:
internalField -- nonuniform List (interpolated LES data)
inlet ------------ calculated nonuniform List (… fully developed channel flow?)
topWall -------- nutLowReWallFunction uniform 3e-18
bottomWall---- nutLowReWallFunction uniform 3e-18
outlet --------- calculated nonuniform List (… fully developed channel flow?)

both top and bottom walls had “calculated” instead of “nutLowReWallFunction”, but simplefoam couldn’t run with calculated. I think nutLowReWallFunction is appropriate.

omega:
internalField ---- uniform 0.11
inlet ------------ fixedValue nonuniform List (… fully developed channel flow?)
topWall --------- omegaWallFunction uniform 1000
bottomWall----- omegaWallFunction uniform 1000
outlet ---------- zeroGradient


k:
internalField ---- nonuniform List (interpolated LES data)
inlet ------------- fixedValue nonuniform List (interpolated LES data)
topWall --------- fixedValue uniform 1e-15
bottomWall----- all fixedValue uniform 1e-15
outlet ---------- zeroGradient
Attached Images
File Type: jpg iteration_progress.jpg (60.7 KB, 18 views)

Last edited by DataDriven; April 1, 2022 at 11:32.
DataDriven is offline   Reply With Quote

Reply

Tags
boundary condition, initial conditions, komegasst, simplefoam, simplefoam initialisation

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
CFD analaysis of Pelton turbine amodpanthee CFX 31 April 19, 2018 18:02
Out File does not show Imbalance in % Mmaragann CFX 5 January 20, 2017 10:20
Velocity vector in impeller passage ngoc_tran_bao CFX 24 May 3, 2016 21:16
Low Mixing time Problem Mavier CFX 5 April 29, 2013 00:00
Error finding variable "THERMX" sunilpatil CFX 8 April 26, 2013 07:00


All times are GMT -4. The time now is 17:19.