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

Help on a case of a Submarine which diverges

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

Reply
 
LinkBack Thread Tools Display Modes
Old   February 13, 2012, 22:11
Post Help on a case of a Submarine which diverges
  #1
New Member
 
Thibaut SIMON
Join Date: Jan 2012
Posts: 5
Rep Power: 4
thibautsimon1 is on a distinguished road
Hi all,

I'm working on a simple case of a submarine in Deep-water with a k-omega SST turbulence model, using simpleFoam resolution.
My problem is that the case always diverges after 1000 iterations, whatever I do on the mesh or in the settings.

Here my settings:


Number of cells: 4 100 000
Re= 1.146 E+006
y+=3.8
aspect ratio <100
Speed=0.717 m/s
Lenght of the hull=1.52m


And here is a part of my fvShemes file:

gradSchemes
{
default Gauss linear;
grad(p) Gauss linear;
grad(U) Gauss linear;
// grad(U) cellLimited Gauss linear 1;
}

divSchemes
{
default none;
div(phi,U) Gauss linearUpwindV grad(U);
div(phi,k) Gauss linearUpwind grad(k);
div(phi,omega) Gauss linearUpwind grad(omega);
div((nuEff*dev(T(grad(U))))) Gauss linear;
}


Someone has any idea of wath I did wrong?
Thanks for your help
thibautsimon1 is offline   Reply With Quote

Old   February 14, 2012, 02:19
Default
  #2
Senior Member
 
linnemann's Avatar
 
Niels Nielsen
Join Date: Mar 2009
Location: NJ - Denmark
Posts: 438
Rep Power: 13
linnemann will become famous soon enough
Hi

Try these settings (OF 2.1).

Also you should always start with upwind on everything if you have stability issues. It's just BPG (Best Practice Guidelines). Also for Marine CFD look at this for BPG
Attached Files
File Type: txt fvSchemes.txt (2.1 KB, 37 views)
File Type: txt fvSolution.txt (1.9 KB, 22 views)
__________________
Linnemann

PS. I do not do personal support, so please post in the forums.
linnemann is offline   Reply With Quote

Old   February 15, 2012, 20:07
Default
  #3
New Member
 
Thibaut SIMON
Join Date: Jan 2012
Posts: 5
Rep Power: 4
thibautsimon1 is on a distinguished road
Thanks a lot for your help,
I change few settings in my fvSchemes file, it seems to work now with this settings:

divSchemes:

div(phi,U) Gauss upwind grad(U);
div(phi,k) Gauss upwind grad(k);
div(phi,omega) Gauss upwind grad(omega);
div(phi,epsilon) Gauss upwind grad(epsilon);
div((nuEff*dev(T(grad(U))))) Gauss linear;
}

laplacianSchemes
{
default Gauss linear corrected;



I didn't change everythings cause I'm using the OF2.0

I let you know of my advances...

Thanks again
thibautsimon1 is offline   Reply With Quote

Reply

Tags
divergence detected, simplefoam, submarin, yplusras

Thread Tools
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 On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Instable natural convection case Peter88 OpenFOAM 5 August 18, 2011 01:23
Superlinear speedup in OpenFOAM 13 msrinath80 OpenFOAM Running, Solving & CFD 17 August 22, 2009 03:59
Transient case running with a super computer microfin FLUENT 0 March 31, 2009 11:20
Is Playstation 3 cluster suitable for CFD work hsieh OpenFOAM 8 March 12, 2008 05:58
Free surface boudary conditions with SOLA-VOF Fan Main CFD Forum 10 September 9, 2006 12:24


All times are GMT -4. The time now is 18:23.