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

detect separation and reattachment points in Fluent

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

Reply
 
LinkBack Thread Tools Display Modes
Old   November 4, 2009, 18:22
Default detect separation and reattachment points in Fluent
  #1
Member
 
Ivan
Join Date: May 2009
Posts: 85
Rep Power: 8
ivanbuz is on a distinguished road
I want to get the separation and reattachment points in time-averaged simulation results, and I am a little frustrated now.

I checked the text books and it says du/dy=0 or dp/dx=0. I searched the forums and there is not much information about how to detect them.

I try plotting "mean x-wall shear stress" in "unsteady wall statistics" of the airfoil, and it seems to me that the separation point is where shear stress=0 (from positive to negative), and the reattachment point is where shear stress=0 again (from negative to positive).

Can anyone show me the correct way to detect these points? Thanks in advance!!!
ivanbuz is offline   Reply With Quote

Old   May 3, 2010, 21:36
Default
  #2
Member
 
thanos
Join Date: Oct 2009
Posts: 30
Rep Power: 7
thanos is on a distinguished road
Hi!

instead of plotting press ''write'' in your X-Y panel and save the file in a .xls format. This will create an excel file. Do it for the shear stress on x axis and then examine the points from your excel file. As you correctly assumed, laminar separation occurs when the shear stress change from positive to negative and reattachment when it changes from negative to positive.

Good luck!
thanos is offline   Reply With Quote

Old   January 20, 2015, 15:10
Default hi reattachment length
  #3
Member
 
-- Please Select (only U.S. / Can / Aus)
Join Date: Sep 2013
Posts: 48
Rep Power: 3
m zahid is on a distinguished road
hi , is it necessary to do the unsteady analysis for the reattachment length or can we measure this by steady analysis. ????

advance thanks
m zahid is online now   Reply With Quote

Reply

Tags
separation reattachment

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



All times are GMT -4. The time now is 03:57.