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

What are the internal numerical data types used by FLUENT?

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   July 16, 2015, 07:18
Default What are the internal numerical data types used by FLUENT?
  #1
Leb
New Member
 
V.Leb
Join Date: Jun 2015
Posts: 8
Rep Power: 11
Leb is on a distinguished road
Hi everyone,

I was wondering what is the default numerical data type FLUENT is using. In the manual I can find this:Lhttp://www.afs.enea.it/project/neptunius/docs/fluent/html/udf/node252.htm

but it's for UDFs.

The reason I'm asking is because I wonder if running a simulation on a mesh that has micro meter scale system expressed in meters (i.e. length scale etc. units are read as meters in FLUENT) would be worse/not converge as fast as one using micro meter scale in FLUENT (i.e. instead of having 0.000001m I would have 1um when FLUENT is calculating). I guess if FLUENT is using at least float precision, then this wouldn't be a problem...

Cheers
Leb is offline   Reply With Quote

Old   July 16, 2015, 12:08
Default
  #2
Senior Member
 
Andrew Kokemoor
Join Date: Aug 2013
Posts: 122
Rep Power: 13
Kokemoor is on a distinguished road
The default is single (float) precision, but double is supported and easy to enable. In the GUI launcher, there's a checkbox for it. If you're launching from command line, add "dp" to the solver flag, e.g. -3ddp instead of -3d.
Kokemoor is offline   Reply With Quote

Old   July 21, 2015, 11:15
Default
  #3
Leb
New Member
 
V.Leb
Join Date: Jun 2015
Posts: 8
Rep Power: 11
Leb is on a distinguished road
Thanks, I realised that after I have posted the question. I'm a bit surprised that it makes a difference in convergence ( I thought floats "dynamic range" would be more than enough...).
Leb is offline   Reply With Quote

Reply

Tags
fluent 12.0, scale factor, units

Thread Tools Search this Thread
Search this Thread:

Advanced Search
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 Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
high continuity Fluent modeling ABL with WRF/CALMET data xitao21 FLUENT 1 May 2, 2019 10:20
OpenFoam to Fluent data conversion Problem vemps OpenFOAM 1 August 8, 2011 02:30
How to read tabulated data in Fluent Siddhartha Pal FLUENT 0 August 30, 2007 05:18
reading data into fluent co2 FLUENT 0 December 28, 2003 01:31
Boundary Types in Fluent 5/6 Oresko FLUENT 3 July 23, 2002 19:23


All times are GMT -4. The time now is 06:09.