CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > OpenFOAM Post-Processing

energy spectra from LES simulations

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

Reply
 
LinkBack Thread Tools Display Modes
Old   October 29, 2009, 10:42
Default energy spectra from LES simulations
  #1
Senior Member
 
Suresh kumar Kannan
Join Date: Mar 2009
Location: Luxembourg, Luxembourg, Luxembourg
Posts: 129
Rep Power: 9
kumar is on a distinguished road
Hello Everybody,

I am using lesInterfoam for running some two phase simulations using the one eq eddy model.
I am doing a mesh convergence study, so i want to compare the energy spectra from different meshes.

I have successfully made a utility called KE which extracts the Total kinetic energy from all the time steps, I made it by changing a few lines of the Lamda2 utility and compiling it, and the utility works fine. i have used something like "0.5*U&U" to extract the Total Kinetic energy. I got this from a post.

Actually I am new to this kind of energy spectra analysis, so iam not sure how to use the total kinetic energy and produce a energy spectra. Any comments from experienced LES users is welcome. Also any literature explaining how to extract energy spectra from Total Kinetic Energy is also welcome.

bye
wiith regards
K.Suresh kumar
kumar is offline   Reply With Quote

Old   February 22, 2016, 11:14
Default
  #2
New Member
 
Mr.liu
Join Date: Sep 2012
Posts: 23
Rep Power: 6
lx882211 is on a distinguished road
Quote:
Originally Posted by kumar View Post
Hello Everybody,

I am using lesInterfoam for running some two phase simulations using the one eq eddy model.
I am doing a mesh convergence study, so i want to compare the energy spectra from different meshes.

I have successfully made a utility called KE which extracts the Total kinetic energy from all the time steps, I made it by changing a few lines of the Lamda2 utility and compiling it, and the utility works fine. i have used something like "0.5*U&U" to extract the Total Kinetic energy. I got this from a post.

Actually I am new to this kind of energy spectra analysis, so iam not sure how to use the total kinetic energy and produce a energy spectra. Any comments from experienced LES users is welcome. Also any literature explaining how to extract energy spectra from Total Kinetic Energy is also welcome.

bye
wiith regards
K.Suresh kumar
Hi, could you tell me how to get the TKE, which parameter should i monitor? Thanks.
lx882211 is offline   Reply With Quote

Old   February 23, 2016, 13:25
Default
  #3
Member
 
Join Date: Jun 2012
Posts: 94
Rep Power: 6
Bazinga is on a distinguished road
You can use probes to monitor the velocity fluctuations at one location at each time steps. With the time series you can calculate your fluctuations and thus your TKE.
You can also use the fieldAverage function object to record prime2mean with which you can also calculate a time averaged TKE in the whole domain.
Check the forum for an explanation of both options.
Hope that helps.
Bazinga 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
LES and total turbulent kinetic energy Boerge FLUENT 1 September 8, 2012 11:41
ATTENTION! Reliability problems in CFX 5.7 Joseph CFX 14 April 20, 2010 15:45
Energy Spectrun for LES simulations Anindya FLUENT 0 March 29, 2006 10:53
Energy Spectra! Murthy FLUENT 0 December 26, 2005 08:42
Energy Spectra! Murthy Main CFD Forum 0 December 26, 2005 08:41


All times are GMT -4. The time now is 10:20.