CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > General Forums > Main CFD Forum

the subgrid scale turbulent kinetic energy?

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   July 21, 2006, 05:30
Default the subgrid scale turbulent kinetic energy?
  #1
mud2003
Guest
 
Posts: n/a
How to account the subgrid scale turbulent kinetic energy in LES simulation??
  Reply With Quote

Old   July 21, 2006, 08:26
Default Re: the subgrid scale turbulent kinetic energy?
  #2
Cut cell
Guest
 
Posts: n/a
You can model the transport equation for the sub-grid scale kinetic energy via its own balance equation - which is quite well defined. Much like the balance equation for the RANS TKE. In the case of the destruction term, epsilon, in the sub-grid case, one uses a mixing length tactic, and models the dissipation based on the local filter width and the local sub-grid k.

Much work has been done by Menon's group at Georgia Tech, and I would consider his work on this, at Industrial level apps. at least, the best in the world. However, his work is for the compressible case which is of interest to me, if you're working with incompressible flow then Lars Davidson is probably your best reference.

A last note, one can either model the constants dynamically, or not, and I would start by using the model constants rather than dynamically computing them...

Cheers

  Reply With Quote

Old   July 21, 2006, 10:21
Default Re: the subgrid scale turbulent kinetic energy?
  #3
mud2003
Guest
 
Posts: n/a
hi...cell "You can model the transport equation for the sub-grid scale kinetic energy via its own balance equation " you mean i need to build a equation to solve the k? but i have not see any reference talk about this. I also use the consant model, and how do you deal with the wall condition? how to solve the y+? thanks!
  Reply With Quote

Old   July 21, 2006, 10:29
Default Re: the subgrid scale turbulent kinetic energy?
  #4
Cut cell
Guest
 
Posts: n/a
You're after quite a bit of information there. It has been done, 10-15 years worth by various people, and longer by others so it is out there. I would read the papers by the people I referenced to get a good understanding of the model, then worry about implementation details etc.

Look in AIAA for Menon, and look on his website for the references at Gerogia Tech, there are many papers. Like I said if you want to consider incompressible flow look at Lars Davidson.

Not sure what you mean by "I also use the consant model", I was talking about something quite subtle to do with test filters etc... I'd ignore that at the moment and get reading!!!
  Reply With Quote

Reply

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
question about turbulent kinetic energy junker4236 Main CFD Forum 19 April 19, 2017 05:46
LES and total turbulent kinetic energy Boerge FLUENT 1 September 8, 2012 12:41
How to view subgrid kinetic energy Craig FLUENT 3 September 8, 2012 12:34
Subgrid Turbulent Kinetic Energy in LES saqure ANSYS 3 September 7, 2012 17:44
LES of periodic pipe centerline turbulent kinetic energy smehdi609 OpenFOAM 0 December 1, 2010 00:59


All times are GMT -4. The time now is 06:24.