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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 10:43

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 11:00

Re: ERROR: Floating point exception: Overflow
 
Hi,

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

alpha February 7, 2008 11:15

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 11:16

Re: ERROR: Floating point exception: Overflow
 
Hello,

try to change the turbulence model to SST. good luck

Elisabetta February 7, 2008 12:27

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 13:12

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 13:42

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 16:55

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

alpha

Elisabetta February 7, 2008 17:22

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 07:50

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 02:19

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

oewnce932c February 28, 2013 10:00

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.

faraday34 June 12, 2013 18:22

Thank you for indicating your solution to the problem, Pjotr.

rezamo January 18, 2014 08:35

hi
 
Quote:

Originally Posted by T
;85922
Hello,

try to change the turbulence model to SST. good luck

hi T i Read your post thanks so much

ghorrocks January 19, 2014 05:57

This is not a very useful thread. A much more complete answer to this question is in the FAQ: http://www.cfd-online.com/Wiki/Ansys...do_about_it.3F

Suraj Marale March 28, 2015 10:16

hello Elisabetta,
I am also working on multiphase flow (air and water).
While solving i got same error just like you. how you solved that error??? Can you please help me for that??

May be i am doing some wrong procedure for multiphase. Please tell me how you solved the problem?? If you have any tutorials please give me... or please tell, what extra boundry conditions i have to apply for multiphase flow... Please reply its urgent..

Thanks in advance... :-)

ghorrocks March 29, 2015 05:26

Elisabetta's post was over 7 years ago. There is not many people who hang around forums for that long. Dinosaurs like me are a rare exception.

Did you read the FAQ I linked to? It gives some detail about what the problem is and what to do about it.

Suraj Marale March 29, 2015 09:52

Yep, I read the FAQ and tried with the different methods which are discussed in that.. but still i am getting the errors,.. may be i did some mistakes in boundry conditions.. something might be missing in boundry condition...
Thats why i am asking for the tutorial for air and water mixture.. so that i can check my boundry conditions...

And something you are talking about tutorials available at ansys customer website, is it same as ansys help tutorials or different???? because there are no tutorials available regarding air and water mixture in ansys help....

please find your valuable time for me and can you please check it and give me the link of tutorials which are available at ansys customer website???
.
Thanks .. waiting for reply...:)

ghorrocks March 29, 2015 18:11

ANSYS Customer website: https://support.ansys.com/portal/sit...CustomerPortal

Suraj Marale March 30, 2015 06:34

thanks for the link glenn, I will check.. :)


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