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

Model Switch, RANS to LES?

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

Reply
 
LinkBack Thread Tools Display Modes
Old   July 7, 2015, 11:30
Default Model Switch, RANS to LES?
  #1
New Member
 
Jenna
Join Date: Nov 2014
Posts: 11
Rep Power: 2
jennap223 is on a distinguished road
Hello,

I am running a spray simulation and was reading a paper recently by C J Rutland called "Large-eddy simulations for internal combustion engines - a review"

The following passage about RANS to LES simulations leads me to believe that one should not simply run a RANS simulation and then if all goes well, re-run it on LES which would involve only changing the turbulence model and SGS submodel for LES. (Obviously, grid requirements would have be addressed)

The passage reads:
Quote:
Models (sometimes called submodels) are required, not only for turbulence, but also for liquid sprays, combustion, and various scalar processes. This means that LES modelling for engines should be more than just using a turbulence model, such as the dynamic Smagorinsky model, and leaving all of the other submodels the same as RANS models. Unfortunately, this approach is fairly common.... Proper use of LES in engines requires potential modification of many submodels to make them consistent within the LES context.
My problem is that I cannot think of anything I would change about my simulation other than changing RANS and its submodel to LES and its submodel (AKA his idea of the "unfortunate, common approach". The gas phases have an Eulerian representation and the liquid injection is represented by a Lagrangian phase and appropriate physics models.

If anyone knows what is meant by that quote in terms of changes aside from turbulence models, please share your insight
jennap223 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
Eulerian multifluid model with LES CFDtoy Main CFD Forum 0 July 11, 2011 11:46
RANS vs.LES turbulence model usker CD-adapco 1 April 3, 2008 18:38
Mapping RANS data onto an LES christian OpenFOAM Running, Solving & CFD 0 April 13, 2007 05:31
heat transfer in LES and RANS ricklee Main CFD Forum 1 September 1, 2005 14:08
2-equation model of LES and source code M.R.Hadian Main CFD Forum 0 February 3, 2002 06:00


All times are GMT -4. The time now is 06:37.