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

Floating point error

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

Reply
 
LinkBack Thread Tools Display Modes
Old   June 12, 2007, 02:49
Default Floating point error
  #1
mvee
Guest
 
Posts: n/a
hi,

I found the message during solution as

Error: Floating point error: invalid number Error object: ()

can anybody tell me about this?

I have tried by

1) Reducing mesh size 2) Changing turbulence model 3) changing turbulence intensity in boundary condition panel 4) Not solving all the equations simultaneously(solve-control-solution panel). Solving the equation one by one or in group of two equations.

I spend lot of time to solve this problem. Can anyone have faced the same one and at the end got the solution, please reply me.

Your failure in this case also may give me the way towards the solution.

thanking you in advance and please reply whatever you know in this respect.

regards, mvee
  Reply With Quote

Old   June 12, 2007, 11:26
Default Re: Floating point error
  #2
rlindsey
Guest
 
Posts: n/a
Hi, I had some of those when I was experiementing with my hardware. I am overclocking my cluster and when I pushed it up too high it will throw those, even if the setup appears stable on some benchmarking tests. I just backed down the speed a little and it's fine.

Are you OC'ing your machines? How old are they? If they get dust in the heatsinks sometimes they will get hot and let an electron go the wrong way... Have you run coretemp or anything to see if your processors are heating up?

I'm sure there are other causes for this but that's the one I ran into.
  Reply With Quote

Old   June 13, 2007, 00:56
Default Re: Floating point error
  #3
Markus Lummer
Guest
 
Posts: n/a
http://www.cfd-online.com/Forum/flue....cgi/read/4193
  Reply With Quote

Old   June 13, 2007, 04:04
Default Re: Floating point error
  #4
mvee
Guest
 
Posts: n/a
Hello Lummer,

I have tried the solution that you have given through the link. I have checked the skewness it is in the range of 0.14. And also i have changed the grid size, reduces the size of grid. About initialization i am confident because i ran the problem with different dimension and it is converged. I am using PISO scheme for Pressure velocity coupling and PRESTO scheme for pressure discretization. So i kept all URF as 1. AT the same time i checked it by changing the URF. Still floating point error is there.

[in your link the author use the word as "numerically stiff situation". What does this mean?]

can you suggest any different scheme?

thanks for your response

regards, mvee
  Reply With Quote

Reply

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


Similar Threads
Thread Thread Starter Forum Replies Last Post
c++ libraries and solver compiling vaina74 OpenFOAM Installation 13 February 3, 2012 18:43
Problem with UDF compiling for kTkLW model Wantami FLUENT 0 July 18, 2011 05:11
Accessing phi from a fvPatchField at same patch johndeas OpenFOAM 1 September 13, 2010 20:23
Version 15 on Mac OS X gschaider OpenFOAM Installation 120 December 2, 2009 11:23
Problem with compile the setParabolicInlet ivanyao OpenFOAM Running, Solving & CFD 6 September 5, 2008 20:50


All times are GMT -4. The time now is 07:38.