CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > Siemens > STAR-CCM+

is it possible to include surface tension in DEM?

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

Reply
 
LinkBack Thread Tools Display Modes
Old   July 13, 2018, 06:53
Default is it possible to include surface tension in DEM?
  #1
New Member
 
Miguel
Join Date: Apr 2018
Posts: 7
Rep Power: 2
synuk75 is on a distinguished road
Hi guys,

apart from the drag and lift forces exerted by the fluid over the particles I woul like to simulate capillary effects. is it possible using DEM?. I only found the option using eulerian-eulerian models...
Thank you
synuk75 is offline   Reply With Quote

Old   July 21, 2018, 02:14
Default
  #2
Senior Member
 
Ping
Join Date: Mar 2009
Posts: 357
Rep Power: 13
ping is on a distinguished road
dem particles are relatively large solids so the concept of surface tension in fluids as caused by molecular attraction does not apply so please explain what force you are wanting to simulate
ping is offline   Reply With Quote

Old   July 23, 2018, 18:17
Default
  #3
New Member
 
Miguel
Join Date: Apr 2018
Posts: 7
Rep Power: 2
synuk75 is on a distinguished road
Hi,

I really appreciate your help,

I am trying to simulate wet sand. sand particles remain together because of capillary forces, (that is why we can build sand castles in the beach). i have decided to simulate this capillary forces including linear cohesion since STAR doesnt allow me to include surface tensions.

what i am realy straggling is that although the water in between the grain particles only occupies a fraction of the continuum (because of the solid grains), when i represent the volume fraction of water the value is 1 all over the domain. however the void fraction seems to be ok and give me values between 0.25 and 1 over the continuum domain. any ideas about what i am doing wrong?



i posted it in another thread but no reponse so far.

thank you very much,
synuk75 is offline   Reply With Quote

Old   July 24, 2018, 00:07
Default
  #4
Senior Member
 
Ping
Join Date: Mar 2009
Posts: 357
Rep Power: 13
ping is on a distinguished road
you can certainly turn on surface tension when dem is enabled but normally surface tension needs two fluids to be present eg in your case air and water and so this is what causes the attractive forces and if there is no air then i would expect there is no surface tension force but this is something i have never explored
ping is offline   Reply With Quote

Reply

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
6DOF simulations with very large motions ommis OpenFOAM Running, Solving & CFD 8 August 15, 2017 03:14
How to add Surface Tension in cavitatingFoam solver jamestangx OpenFOAM Programming & Development 1 April 6, 2016 16:39
Help!! customize surface tension term in interFoam w051cxw OpenFOAM Running, Solving & CFD 0 February 12, 2016 01:15
VOF and strong surface tension effect phsieh2005 Main CFD Forum 1 August 30, 2005 06:56
surface tension model in EX26 Junhua Wu FLUENT 0 June 7, 2000 10:49


All times are GMT -4. The time now is 10:22.