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-   -   Floating error (http://www.cfd-online.com/Forums/star-ccm/70207-floating-error.html)

Arconis November 17, 2009 06:27

Floating error
 
Hi, i'm getting a floating point exception just after running the simulation, before any iteration complete. (It takes several minutes)

It happened in two cases:

- When i use ideal gas model with a specified temperature and a catalyst.

I solved that running as constant density 100 iterations and then switching to ideal gas

- Using constant density model with a filter (porous region).

Solved running with fluid region filter 20 iterations and then changing it to porous region


Can you tell me if i did it well or there's another or easier solution?


Server Error: A floating point exception has occurred: floating point exception [Invalid operation]. The specific cause cannot be identified.

ping November 25, 2009 00:35

Ideal gas is much more sensitive and can take a bit of effort to get going occasionally - here are some ideas:
try reducing the under-relaxation factors
use better initial conditions
your boundary conditions might be too radial for the steady solver - reduce their values by an order of magnitude or two and step them up again as the solution develops
change to the implicit transient solver

Arconis November 25, 2009 03:23

thx ping, i'll try that

sheikh nasir February 8, 2012 03:09

Floating error
 
Hello
i am getting floating error:invalid number. I am working on train travelling in tunnel. Can any body help me. My email is sheikhnasir39@gmail.com

thanks

abdul099 February 18, 2012 06:52

What about a little bit more information on the problem, setup etc.? I lost my crystal ball last week, so I'm no visionary anymore...

Quote:

Originally Posted by sheikh nasir (Post 343285)
Hello
i am getting floating error:invalid number. I am working on train travelling in tunnel. Can any body help me. My email is sheikhnasir39@gmail.com

thanks


sheikh nasir February 18, 2012 09:12

floating errror
 
hello,
i am using gambit and fluent for my analysis i.e train moving in tunnel. i am trying for 2D analysis. but i am getting floating error; invalid number. plz help me

abdul099 February 18, 2012 10:08

Quote:

Originally Posted by sheikh nasir (Post 345105)
hello,
i am using gambit and fluent for my analysis i.e train moving in tunnel. i am trying for 2D analysis. but i am getting floating error; invalid number. plz help me

Did you ever think about the reason why there's a different forum for every software? What the f... do you think should somebody answer without knowledge of the software used by you?
This is the forum for STAR-CCM+ forum, N O T gambit and fluent

Ask in the gambit and or fluent forum, maybe you will get an answer there. And if not, DO NOT ask here again, you won't get an answer here nearly for sure!


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