# Lamda 2 criterion for vortex identification

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

 October 10, 2006, 22:15 Lamda 2 criterion for vortex identification #1 Aindya Guest   Posts: n/a How can I calculate the Lambda 2 criterion for vortex identification in Fluent? I am studying the flow over a bluff body using LES. Thanks for your help. Anindya

 October 11, 2006, 13:23 Re: Lamda 2 criterion for vortex identification #2 sarah_ron Guest   Posts: n/a I think you could do it by UDF or custom defined function.

 June 4, 2011, 12:34 #3 New Member   Join Date: Feb 2011 Posts: 2 Rep Power: 0 Hi, could anyone please write a step-by-step way to calculate lambda 2 in Fluent, Tecplot or Paraview? Cheers

 June 6, 2011, 11:55 #4 Member   Neil Join Date: Jun 2009 Location: The Moon Posts: 42 Rep Power: 10 You can easily extract vortex cores in Tecplot which should show you what large scale coherent structures are present in the flow. I can't remember how its done as there are 2 methods to calculate it but either way you are going to get something relatively similar to what the lambda-2 criterion would calculate. I know under tools there is an option for the tensor eigensystem (once you've edited the .add file). Found this link for it which fortunately describes it use for calculating the lambda-2 criterion. http://tecplottalk.com/addons/tensoregn/ If you are looking for coherent structures in the flow you could possibly think about doing a POD analysis for the first few modes if you have enough data. As I've found this to be great for extracting underlying flow structures which I wouldn't of otherwise known about. Neil

 June 7, 2011, 03:51 #5 New Member   Join Date: Feb 2011 Posts: 2 Rep Power: 0 Hi Neil! Thank you for your quick reply. I found it. The Contours issue of Tecplot on how to calculate lambda 2 is not available any more online.. Instead the calculation is described in Tecplot's user's manual (http://download.tecplot.com/360/tpum.pdf). Cheers, Светлана likes this.

 April 3, 2017, 22:39 #6 Member   yehanyu Join Date: Mar 2012 Location: Beijing, China Posts: 46 Rep Power: 7 You can use the ANSYS CFD-Post.

 Thread Tools Display Modes Linear Mode

 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 OffTrackbacks are On Pingbacks are On Refbacks are On Forum Rules

 Similar Threads Thread Thread Starter Forum Replies Last Post tH3f0rC3 OpenFOAM 7 February 23, 2013 06:37 tH3f0rC3 OpenFOAM 6 May 16, 2011 04:32 Iain Main CFD Forum 0 May 5, 2008 19:45 Dominique FLUENT 5 November 24, 2006 03:36 Vidya FLUENT 5 August 6, 2006 16:46

All times are GMT -4. The time now is 04:49.