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

Numerical Instability: decreasing timestep with interFoam

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   January 22, 2019, 10:27
Default Numerical Instability: decreasing timestep with interFoam
  #1
New Member
 
Join Date: Oct 2018
Posts: 1
Rep Power: 0
beknrbow is on a distinguished road
Hello CFD community,


I am having major stability problems when running a fairly simple case in interFoam. I meshed a pipe connected to a tank using blockMesh. Water should flow through the tube and drop down into the tank that overflows once the water level reaches the outlet.


I have kept the space discretization simple. I have tried refining the mesh more but my time step keeps dwindling until it becomes a floating point error. I can barely simulate 0.03 seconds. I would like to know if you have any good tips/strategies for meshing and ensuring the courant number is kept below 1 because up to this point I have basically just been guessing and working through trial and error.


I have provided an image of the mesh below as well as the case file which you can find attached as a zip file. You should run blockMesh as I emptied the polymesh file to keep the file size at a bare minimum. Thank you in advance!
Attached Images
File Type: png dropcase.png (48.9 KB, 21 views)
Attached Files
File Type: zip V6_cylinder_drop.zip (16.6 KB, 8 views)
beknrbow is offline   Reply With Quote

Old   March 22, 2019, 23:35
Default
  #2
Senior Member
 
krishna kant
Join Date: Feb 2016
Location: Hyderabad, India
Posts: 133
Rep Power: 10
kk415 is on a distinguished road
Hello,


I am facing a same problem for solving a swirl jet atomizer. Any help is deeply appreciated.
kk415 is offline   Reply With Quote

Reply


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
NUMERICAL INSTABILITY FOR FLOW OV. SWIRLING VANES D FLUENT 3 February 9, 2005 15:35
NUMERICAL INSTABILITY OVER THE SWIRLING VANES Dan Main CFD Forum 2 February 9, 2005 08:12
Instability of convection Zeng Main CFD Forum 0 May 26, 2000 05:39
New Books and Numerical Software Eleuterio TORO Main CFD Forum 0 December 18, 1998 12:41
Problems of numerical instability because of high gradients Xiangyang Ye Main CFD Forum 4 September 28, 1998 03:48


All times are GMT -4. The time now is 03:22.