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

Plotting turbulent energy spectra in Matlab

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

Reply
 
LinkBack Thread Tools Display Modes
Old   April 23, 2009, 19:18
Default Plotting turbulent energy spectra in Matlab
  #1
New Member
 
Nathan
Join Date: Apr 2009
Posts: 3
Rep Power: 8
nathanpetrelli is on a distinguished road
Hi guys,
I have one dimensional velocity component stored in a matrix over time. (The different rows represent velocity over different time.)

If I want to plot the turbulent energy spectra from here in Matlab, how do I go about it?
nathanpetrelli is offline   Reply With Quote

Old   April 24, 2009, 08:45
Default
  #2
Senior Member
 
Aroon
Join Date: Apr 2009
Location: Racine WI
Posts: 148
Rep Power: 8
vishyaroon is on a distinguished road
Have you tried the psd functions in MATLAB. I guess there is also a p.welsh command that you can use.
vishyaroon is offline   Reply With Quote

Old   April 24, 2009, 22:57
Default
  #3
New Member
 
Nathan
Join Date: Apr 2009
Posts: 3
Rep Power: 8
nathanpetrelli is on a distinguished road
Aroon,

Thanks for your reply..

I have been trying to first use fft to change the velocity into wavenumber space. Once I have done this, am trying to apply the pwelch function, but I seem to be getting a garbage plot.Nothing that looks like -5/3, but more like random noise.
nathanpetrelli 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 Spectra! Murthy Main CFD Forum 0 December 26, 2005 08:41
calculation of (turbulent) dissipation energy ? max Main CFD Forum 3 August 18, 1999 09:42
turbulent energy spectra ulrich bieder Main CFD Forum 8 June 25, 1999 10:27


All times are GMT -4. The time now is 19:12.