CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > ANSYS > FLUENT

Eulerian Modeling: Frictional Viscosity Help

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   July 8, 2009, 15:46
Default Eulerian Modeling: Frictional Viscosity Help
  #1
Member
 
Casey
Join Date: Jun 2009
Posts: 98
Rep Power: 17
meangreen is on a distinguished road
Dear All,
I tried to make a UDF to mimic the frictional viscosity (Schaeffer) coded inside of fluent, but I was not able to do it. I know fluent sets a limit of 10^5 for the frictional viscosity, but I dont know how fluent deals with the frictional viscosity when the deviatoric strain rate is zero (since this is in the denominator or the frictional viscosity). I am simulating a bed of particles interacting with a jet of gas, so initially the particles aren't moving and I am having trouble with my UDF finding a way to properly limit the frictional viscosity. I tried using something where if deviatoric strain < 10^-12 then frictional viscosity = (Pf*sin(phi))/(solidsvof*10^-12). However, when I did this I still could not repeat the simulation results had found. Even with a higher limit on the frictional viscosity, the bed in my case was more liquid like than the fluent case.

Can anyone help? I have been banging my head against this problem for weeks. Let me know if you need more information.
Thanks,

casey

meangreen is offline   Reply With Quote

Old   January 25, 2018, 16:13
Default
  #2
New Member
 
Join Date: May 2015
Posts: 9
Rep Power: 11
trbprnz is on a distinguished road
Hi, did you eventually solve your problem? BR, Alex
trbprnz is offline   Reply With Quote

Reply

Tags
frictional viscosity


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
Multiphase flow (Eulerian) modeling Umesh FLUENT 5 December 29, 2014 11:06
modeling atomization using the Eulerian approach Hossam FLUENT 1 October 4, 2008 07:48
kinematic viscosity at diff temperatures,pressures Mecobio Main CFD Forum 0 November 7, 2005 13:55
Frictional viscosity in granular model Hp FLUENT 4 June 1, 2004 21:42
Modeling turbulence with Eulerian model Eric OLMOS FLUENT 0 March 9, 2000 06:04


All times are GMT -4. The time now is 23:45.