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

VAWT using AMI very high courant number or very small time step

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

Reply
 
LinkBack Thread Tools Display Modes
Old   April 1, 2013, 15:41
Default VAWT using AMI very high courant number or very small time step
  #1
New Member
 
Julio Silveira
Join Date: Feb 2013
Location: London
Posts: 15
Rep Power: 4
biau is on a distinguished road
Dear all,

I am trying to set up a simulation for a VAWT in OpenFOAM. I can simulate it well in fluent,but I need more computational power. I am currently trying to use OpenFoam in order to be able to use a cluster. At the moment I am trying to simulate a 2D VAWT inside a wind tunnel, so later i can do a 3D in a much more refined mesh.

My OpenFoam version is 2.1.1

I am currently trying a laminar case using cyclicAMI for my sliding interfaces. But after few times steps, the courant number start to go very very high and then the simulation crashes. If i limit the courant number, it will adjust the time step for something very very small which would take forever to compute.

Any help would be appreciated.

Thank you

case file in following link:

https://www.dropbox.com/sh/bg0kos6qrg6jufq/om0HkZSmtn
biau is offline   Reply With Quote

Old   April 2, 2013, 06:45
Default
  #2
New Member
 
Håkon Bartnes Line
Join Date: Mar 2013
Posts: 27
Rep Power: 4
hakonbar is on a distinguished road
Did you remember to split the baffles between the two cell zones?

I think the command is "createOrSplitBaffles -split -overwrite", but you can find it in the file called "Allrun.pre" in the pimpleDyMFoam/propeller tutorial.
hakonbar is offline   Reply With Quote

Old   April 2, 2013, 09:13
Default simulation
  #3
New Member
 
Julio Silveira
Join Date: Feb 2013
Location: London
Posts: 15
Rep Power: 4
biau is on a distinguished road
it seemed to help. Lets see how it goes.

Thank you
biau is offline   Reply With Quote

Reply

Tags
ami, openfoam, vawt

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
How to write k and epsilon before the abnormal end xiuying OpenFOAM Running, Solving & CFD 8 August 27, 2013 15:33
same geometry,structured and unstructured mesh,different behaviour. sharonyue OpenFOAM Running, Solving & CFD 13 January 2, 2013 23:40
alphaEqn.H in twoPhaseEulerFoam cheng1988sjtu OpenFOAM Bugs 14 September 18, 2011 13:46
Very high courant number, time step continuity errors and bounding epsilon erncyc OpenFOAM Running, Solving & CFD 1 March 24, 2011 12:00
Transient simulation not converging skabilan OpenFOAM Running, Solving & CFD 12 September 17, 2007 17:48


All times are GMT -4. The time now is 05:51.