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-   -   ERROR: Floating point exception: Overflow (http://www.cfd-online.com/Forums/cfx/25194-error-floating-point-exception-overflow.html)

Elisabetta February 7, 2008 09:43

ERROR: Floating point exception: Overflow
 
Hello everybody.

I'm running a simulation about a multiphase flow (air and dispersed water particles).

On CFX - Solver I got this error:

ERROR #001100279 has occurred in subroutine ErrAction.

Floating point exception: Overflow

Do you know which could be my mistake?

Thank you

Elisabetta

Toralf February 7, 2008 10:00

Re: ERROR: Floating point exception: Overflow
 
Hi,

that is a common question here. Please use the search function ! regards

alpha February 7, 2008 10:15

Re: ERROR: Floating point exception: Overflow
 
I am struggling with same problem. If you find the answer please let me know how you resolved the issue.

By the i am using upwind scheme and small physical time step (for steady state) to run the case and it seems to be working for now. You could try the same. Later i intend to use this solution to run my transient case.

alpha

T February 7, 2008 10:16

Re: ERROR: Floating point exception: Overflow
 
Hello,

try to change the turbulence model to SST. good luck

Elisabetta February 7, 2008 11:27

Re: ERROR: Floating point exception: Overflow
 
Hello again,

I was reading the 'old' post and trying the solutions you suggested me. Now I will change the turbulence model and after that i will let you know.

Thanks a lot

Elisabetta

alpha February 7, 2008 12:12

Re: ERROR: Floating point exception: Overflow
 
Hi

My solution is running now and i am not getting "floating oint exception: overflow" error anymore. However, i am not being able to achieve convergence. My resilduals become flat and i do not observe any change in them for long periods. So i am facing another issue here.

alpha

Peter February 7, 2008 12:42

Re: ERROR: Floating point exception: Overflow
 
Hi,

A few suggestions....I am also new though...

1) Check your boundary conditions. It should always be sensible. Try to keep outlets away from the critical zone.

2) Small time steps make sense. But in my experience small time step with steady state does not give much benefits. What I mean is - you decrease your time step, convergence is very slow and you loose the benefits of solving a steady state problem. Also, all the flows are actually unsteady but a few of them can be solved with steady state solver to get an average result. Now if your flow is no where close to steady state flow, then solver is forcing the equations to reach ONE steady state and then simulation start diverging. In such situations, try using transient simulation. They should go very well with High Resolution scheme with out any flow field as initial condition. And if your flow is really steady state, you can monitor a few points in your domain to see if steady state if obtained after some time.

Peter

alpha February 7, 2008 15:55

Re: ERROR: Floating point exception: Overflow
 
Thank you peter that was helpful.

alpha

Elisabetta February 7, 2008 16:22

Re: ERROR: Floating point exception: Overflow
 
Hello

I did it at the end, thanks to all of you for your answer.

My case seems working better switching the turbulence model to SST and reducing the timestep.

See you again

Bye

Elisabetta

shehab February 21, 2008 06:50

Re: ERROR: Floating point exception: Overflow
 
Hi Elisabetta : my name is shehab. I'm a PhD student in UK and I'm using the multiphase flow to simulate solid particles in water flow. I'm new here in CFX and it seems like I have the same problem you have faced here. How could you solve this problem ?. my e-mail is : shebos@hotmail.com waiting for your reply urgently. shehab

A_Prakash December 23, 2012 01:19

Check the units!
 
Confirm your domain extent units in .out file.

oewnce932c February 28, 2013 09:00

hi.
running an open water propeller simulation in a real dimensions(D=8m, n=100 rev/min). At the beginning of calculation 15..17 Iteration
got the same problem:
ERROR #001100279 has occurred in subroutine ErrAction.
Message:
Floating point exception: Overflow

my solution was:
making timestep smaller from 0.01sek to 0.005sek

now it is running well.


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