# Flow past a sphere

 User Name Remember Me Password
 Register Blogs Members List Search Today's Posts Mark Forums Read

December 17, 2009, 17:10
#21
Member

Muhammed Asmail
Join Date: Nov 2009
Location: Iraq
Posts: 43
Rep Power: 9
Quote:
 Originally Posted by thecfduser Hi For the realtion between Re and Nu, i dont know it, but it is sure that u can find a lot of correlations in bibilography... For the Strouhal number, it is not easy... U must monitor data in a point that is behind ure sphere, then give this data to Matlab and do a fast fourrier transform to get the frequency of ure eddies....Once u have this frequency, u can calculate the Stouhal number...I dont know if this number is affected by temperature in ure case... Regards
dear Karine
please give me the options of fluent to reach strouhal number field
regards

 December 17, 2009, 18:47 #22 Senior Member   karine Join Date: Nov 2009 Posts: 158 Rep Power: 9 Hi Muhammed I dont know how to do it in Fluent I do it on Matlab In fluent, put a point behind ure sphere and monitor velocity in it. The data that u will get, u must treat it on Matlab with a fast fourrier transform to get the frequency of ure coherent structures. If ure Re is <120 (i think) u will not get any vortex schedding: u will get a toroidal vortex.... (there is no strouhal number field: there is ONE Strouhal number in ure flow) Hope that i was clear

December 18, 2009, 04:00
#23
Member

Muhammed Asmail
Join Date: Nov 2009
Location: Iraq
Posts: 43
Rep Power: 9
Quote:
 Originally Posted by thecfduser Hi Muhammed I dont know how to do it in Fluent I do it on Matlab In fluent, put a point behind ure sphere and monitor velocity in it. The data that u will get, u must treat it on Matlab with a fast fourrier transform to get the frequency of ure coherent structures. If ure Re is <120 (i think) u will not get any vortex schedding: u will get a toroidal vortex.... (there is no strouhal number field: there is ONE Strouhal number in ure flow) Hope that i was clear
Dear Karine
in the past and by chance and from options of fluent , i found the box contain Strouhal Number but i forget the option and help of my fluent not found in my computer,please can you find this option from your help of your fluent ,can you send example in the matlab in order to strouhal Number to my e-mail(muham76@yahoo.com)
many thanks

 December 18, 2009, 16:32 #24 Senior Member   karine Join Date: Nov 2009 Posts: 158 Rep Power: 9 Hi In fact, Fluent is able to do a FFT but i had ever tried it....it is bette anyway to do it on matlab ot mathematica... for matlab i dont have it for instance to help u ...sorry...but if i rememeber good, the function name is FFT hope that somebody can help u more

 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 CHEN Main CFD Forum 1 January 30, 2010 03:12 Mahesh Bailakanavar FLUENT 0 February 14, 2008 01:21 lisa Main CFD Forum 2 August 30, 2005 16:36 roland schmehl Main CFD Forum 3 August 21, 2001 13:29 srijit goswami Main CFD Forum 3 January 27, 2001 08:28

All times are GMT -4. The time now is 13:40.

 Contact Us - CFD Online - Privacy Statement - Top