CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > ANSYS > CFX

FloatinPoint Error in LES

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   March 19, 2004, 11:16
Default FloatinPoint Error in LES
  #1
Meri
Guest
 
Posts: n/a
Hello, I have been strugling with a floating point error while using the Large Eddy Simulation method in CFX 5.6, I wondered if there is any one out here who has used this or if there is any verification work done. I know its a short in the dark, but I am kinda stuck Meri
  Reply With Quote

Old   March 21, 2004, 16:37
Default Re: FloatinPoint Error in LES
  #2
Glenn Horrocks
Guest
 
Posts: n/a
Hi Meri,

Floating point errors generally mean a very rapid local divergence. Assuming everything else is OK, in a transient problem the normal fix for this is to reduce the timestep size.

Glenn
  Reply With Quote

Old   March 22, 2004, 06:52
Default Re: FloatinPoint Error in LES
  #3
Meri
Guest
 
Posts: n/a
Glenn, Thanks a lot !, I reduced the time step to 0.0001s for a 2 sec simulation and its working fine.
  Reply With Quote

Old   March 22, 2004, 16:45
Default Re: FloatinPoint Error in LES
  #4
Glenn Horrocks
Guest
 
Posts: n/a
Hi Meri,

It is normal for an LES simulation to require a rediculously small timestep.

Glenn
  Reply With Quote

Reply


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 Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
LES basic and simple questions. dshawul Main CFD Forum 0 October 4, 2010 10:56
Turbulence dampening due to magnetic field in LES and RAS eelcovv OpenFOAM 0 June 8, 2010 11:35
LES grid mesh L3munoz Main CFD Forum 0 April 7, 2010 05:05
LES and combustion model Margherita Cadorin CFX 0 October 29, 2008 05:24
Some Questions about LES. Bin Li Main CFD Forum 2 February 20, 2004 09:58


All times are GMT -4. The time now is 04:17.