CFD Online Logo CFD Online URL
Home > Forums > Software User Forums > OpenFOAM > OpenFOAM Running, Solving & CFD

icoFoam crash with unreasonable velocity.

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

LinkBack Thread Tools Search this Thread Display Modes
Old   November 19, 2011, 21:24
Default icoFoam crash with unreasonable velocity.
New Member
Join Date: Jun 2010
Posts: 6
Rep Power: 15
Bylund is on a distinguished road

A question from an inexperienced OpenFOAM user.

I am playing around with a simple manifold design and icoFoam.

After 10 time steps everything looks more or less ok, but then suddenly the velocity increases to unreasonable values.

I increased the resolution of the mesh with unchanged results.

I have this problem generally with icoFoam that U increases until icoFoam crashes with a floating point error.

I understand I am doing something wrong, so if someone could point me in the right direction I would appreciate it.

Thank you.
Attached Images
File Type: jpg Timestep_10.jpg (62.3 KB, 19 views)
File Type: jpg Timestep_11.jpg (70.6 KB, 17 views)
File Type: jpg Timestep_11_U_max.jpg (61.0 KB, 15 views)
Bylund is offline   Reply With Quote

Old   November 20, 2011, 19:38
New Member
Join Date: Jun 2010
Posts: 6
Rep Power: 15
Bylund is on a distinguished road
I think I found the reason for this problem.

After decreasing deltaT from 0.1 to 0.005 it seems to work good.

Could be useful for anyone else who stumbles upon this problem.
Mechanical Engineer
Bylund is offline   Reply With Quote

Old   November 20, 2011, 21:48
Senior Member
Alberto Passalacqua
Join Date: Mar 2009
Location: Ames, Iowa, United States
Posts: 1,912
Rep Power: 35
alberto will become famous soon enoughalberto will become famous soon enough
Hint: Check that the Courant number is < 1. If you need large time-steps, use pimpleFoam.
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:
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


crash, icofoam, openfoam

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
help with UDF for contact angle based on contact line velocity gandesk Fluent UDF and Scheme Programming 14 October 29, 2012 14:58
Steady pipe flow mean velocity higher than inlet velocity anita OpenFOAM Running, Solving & CFD 7 September 25, 2012 06:35
Velocity in Porous medium : HELP! HELP! HELP! Kali Sanjay Phoenics 0 November 6, 2006 07:10
Velocity output error after scaling mesh in icoFoam philippose OpenFOAM Running, Solving & CFD 4 October 9, 2006 17:51
what the result is negatif pressure at inlet chong chee nan FLUENT 0 December 29, 2001 06:13

All times are GMT -4. The time now is 03:21.