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

simple Foam empty solution

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   April 3, 2012, 12:35
Default simple Foam empty solution
  #1
New Member
 
Debb
Join Date: Sep 2011
Location: Toronto, Canada
Posts: 20
Rep Power: 14
tellico is on a distinguished road
I'm trying a channel (with one two bends) in simpleFoam, it seems to be running without errors but when I look at the results in paraView I only see the inlet and outlet vectors, and nothing is happening in the actual channel throughout the 20 second run

my U conditions are the following:

internalField uniform ( 0 0 0 );

boundaryField
{

inlet
{
type fixedValue;
value uniform ( 0.2 0 0 );
}
Wall1 //all the walls are defined in the same manner
{
type fixedValue;
value uniform ( 0 0 0 );
}
Outlet
{
type fixedValue;
value uniform ( 0 -0.2 0 );
}

is there anything obvious that I am missing here?

any help would be much appreciated.
Attached Images
File Type: jpg Screenshot.jpg (40.4 KB, 18 views)
tellico is offline   Reply With Quote

Old   April 3, 2012, 13:40
Default
  #2
New Member
 
arash
Join Date: May 2011
Posts: 11
Rep Power: 14
arash1 is on a distinguished road
Hi,
I think the problem stems from the fact that setting a fixed value for velocity in outlets makes the solution unstable and may result in strange solutions. you may try runnig the case with zero gradient B.C. for velocity in the outlet.
arash1 is offline   Reply With Quote

Old   April 3, 2012, 16:03
Default
  #3
New Member
 
Debb
Join Date: Sep 2011
Location: Toronto, Canada
Posts: 20
Rep Power: 14
tellico is on a distinguished road
thanks for the info, I changed the outlet value as per your instructions but I'm still getting an almost empty solution, and most of the glyphs are outside of the volume, coming off a wall, rather than the outlet, so I'm assuming that my solution is still unstable

are there any "tricks" that might be useful here to get a stable solution?
tellico is offline   Reply With Quote

Old   April 4, 2012, 01:52
Default
  #4
kid
Senior Member
 
cfdkid
Join Date: Mar 2009
Posts: 133
Rep Power: 17
kid is on a distinguished road
Hello,
We would require more inputs like U,p,RASProperties files.
Use dropbox/box account and use a public link to the picture/file to share the full case.

Hope you co-operate.

regards
CFDkid
kid is offline   Reply With Quote

Old   April 4, 2012, 02:33
Default
  #5
Senior Member
 
Alberto Passalacqua
Join Date: Mar 2009
Location: Ames, Iowa, United States
Posts: 1,912
Rep Power: 36
alberto will become famous soon enoughalberto will become famous soon enough
How did you generate the mesh? I am asking because I noticed a similar issue with one imported mesh.
__________________
Alberto Passalacqua

GeekoCFD - A free distribution based on openSUSE 64 bit with CFD tools, including OpenFOAM. Available as in both physical and virtual formats (current status: http://albertopassalacqua.com/?p=1541)
OpenQBMM - An open-source implementation of quadrature-based moment methods.

To obtain more accurate answers, please specify the version of OpenFOAM you are using.
alberto is offline   Reply With Quote

Old   April 4, 2012, 09:06
Default
  #6
New Member
 
Debb
Join Date: Sep 2011
Location: Toronto, Canada
Posts: 20
Rep Power: 14
tellico is on a distinguished road
I've attached my files. I generated the mesh using blockMesh. This morning I found an error in my blockMesh file and feeling a bit dumb about it (was missing a wall, and I only figured this out by building the geometry out of cardboard and labeling all the faces).

But still not really showing much within the geometry after I run a simulation.
Attached Files
File Type: zip channel.zip (6.3 KB, 2 views)
tellico is offline   Reply With Quote

Old   April 4, 2012, 17:20
Default
  #7
New Member
 
Debb
Join Date: Sep 2011
Location: Toronto, Canada
Posts: 20
Rep Power: 14
tellico is on a distinguished road
I've uploaded the complete file folder to drop box https://www.dropbox.com/sh/1o5m7ukgl2fqkaf/qqbzctfKKT
tellico is offline   Reply With Quote

Reply

Tags
simplefoam convergence


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
Convergence Centurion2011 FLUENT 48 June 14, 2022 23:29
[Other] cgnsToFoam problems with "QUAD_4" cells lentschi OpenFOAM Meshing & Mesh Conversion 1 March 9, 2011 04:49
simple algorithm, converge of solution bbasal Main CFD Forum 0 February 13, 2010 02:58
Strange Solution for a simple pipe flow!! shekharc Main CFD Forum 4 May 9, 2005 09:21
[Gmsh] Import gmsh msh to Foam adorean OpenFOAM Meshing & Mesh Conversion 24 April 27, 2005 08:19


All times are GMT -4. The time now is 02:46.