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

Coherent structures

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

Reply
 
LinkBack Thread Tools Display Modes
Old   July 19, 2011, 18:53
Default Coherent structures
  #1
Member
 
M. Nabi
Join Date: Jun 2009
Posts: 41
Rep Power: 8
mnabi is on a distinguished road
Hi all;

In order to plot the coherent structure of turbulence, I use the formulation proposed by Hunt et al. (1988) as

Q=-\frac{1}{2} \frac{\partial u_i}{\partial x_j} \frac{\partial u_j}{\partial x_i} = -\frac{1}{2} \left( |S|^2 - |\Omega|^2 \right)

Q will include positive and negative values. Can anybody explain it to me, what is different between positive Q and negative values of Q? Does it have a physical meaning?

Thanks
Nabi
mnabi 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
unsteady flow with coherent structures pandora CFX 11 March 27, 2011 18:19
hydraulic structures - bridges and culverts Paul Main CFD Forum 1 March 10, 2011 07:36
Group effects & fluid structures diaw Main CFD Forum 1 October 27, 2006 06:04
Unsteady flow structures - time development diaw Main CFD Forum 4 December 13, 2005 06:15
Convection velocity of Coherent structures Jongdae Kim Main CFD Forum 3 February 5, 2002 05:04


All times are GMT -4. The time now is 03:47.