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

alpha1 is unbounded

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

Reply
 
LinkBack Thread Tools Display Modes
Old   October 17, 2012, 04:48
Default alpha1 is unbounded
  #1
Senior Member
 
Gerhard Holzinger
Join Date: Feb 2012
Location: Austria
Posts: 195
Rep Power: 17
GerhardHolzinger will become famous soon enoughGerhardHolzinger will become famous soon enough
Hello,

I am trying to simulate a bubble column with twoPhaseEulerFoam. When running my case alpha1 reaches values that should not be possible.

Code:
Courant Number mean: 0.00734422 max: 0.637501
Max Ur Courant Number = 0.453228
Time = 0.675

MULES: Solving for alpha1
Dispersed phase volume fraction = 0.000455625  Min(alpha1) = -0.00187942  Max(alpha1) = 1
MULES: Solving for alpha1
Dispersed phase volume fraction = 0.000455625  Min(alpha1) = -0.540265  Max(alpha1) = 1
There is some checker-boarding next to the inlet. Does anyone have some tips how to eliminate that.
Attached Images
File Type: jpg checkerBoardingAlpha1.jpg (12.4 KB, 27 views)
Attached Files
File Type: gz bubbleColumn.tar.gz (5.7 KB, 6 views)
GerhardHolzinger is offline   Reply With Quote

Old   October 17, 2012, 05:25
Default
  #2
Senior Member
 
akidess's Avatar
 
Anton Kidess
Join Date: May 2009
Location: Delft, Netherlands
Posts: 1,163
Rep Power: 20
akidess will become famous soon enough
Try using a much smaller time step.
__________________
*On twitter @akidTwit
*Spend as much time formulating your questions as you expect people to spend on their answer.
*Join the OpenFOAM stackexchange Q&A site: http://area51.stackexchange.com/prop...oHPxcPqde7HtA2
akidess is offline   Reply With Quote

Reply

Tags
twophaseeulerfoam

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
Multiple floating objects CKH OpenFOAM Running, Solving & CFD 12 March 21, 2016 14:05
Formulation in compressibleInterFoam scttmllr OpenFOAM Running, Solving & CFD 55 November 12, 2015 03:07
Problem with interFoam; Wave/wiggle alpha1 behavior JonW OpenFOAM 3 February 23, 2013 21:41
Boundedness of alpha1 in twoLiquidMixingFoam and interMixingFoam gopala OpenFOAM Running, Solving & CFD 4 October 25, 2012 06:57
Alpha1 is reducing..... Whyman OpenFOAM 8 October 16, 2012 10:08


All times are GMT -4. The time now is 04:37.