CFD Online Discussion Forums

CFD Online Discussion Forums (http://www.cfd-online.com/Forums/)
-   OpenFOAM Running, Solving & CFD (http://www.cfd-online.com/Forums/openfoam-solving/)
-   -   I got complete different results for pisofoam and pimplefoam? (http://www.cfd-online.com/Forums/openfoam-solving/95368-i-got-complete-different-results-pisofoam-pimplefoam.html)

lakeat December 14, 2011 18:47

I got complete different results for pisofoam and pimplefoam?
 
I got completely different results for pisofoam and pimplefoam.

"completely" means, the resulting strouhal numbers are so different, as the former is almost twice bigger than the second.

2D and 3D are all tested, and also with a variety of turb models, etc.

All the other settings are the same.

I am very surprised. :eek:

su_junwei December 14, 2011 22:00

Quote:

Originally Posted by lakeat (Post 335854)
I got completely different results for pisofoam and pimplefoam.

"completely" means, the resulting strouhal numbers are so different, as the former is almost twice bigger than the second.

2D and 3D are all tested, and also with a variety of turb models, etc.

All the other settings are the same.

I am very surprised. :eek:

It seems that pisoFoam is a totally transient, the simulation results are the resultes on time point. PimpleSimpleFoam is not a totally transient, it has a relaxation on each time step, thus, the results should be the average results over a given time step.

Junwei

lakeat December 14, 2011 22:09

There might be a bug in pisofoam, the one I downloaded. I am double-checking it.

hfs November 7, 2012 15:19

Hello!

I am interested in the comparison ... did you find out what is wrong??

michael1023 December 26, 2012 22:28

Quote:

Originally Posted by lakeat (Post 335854)
I got completely different results for pisofoam and pimplefoam.

"completely" means, the resulting strouhal numbers are so different, as the former is almost twice bigger than the second.

2D and 3D are all tested, and also with a variety of turb models, etc.

All the other settings are the same.

I am very surprised. :eek:

What case did you take, flow past over a circular cylinder? Could you show the results to me?
Thank you.

Zhou Qiang

hfs December 27, 2012 03:26

Hello Zhou,

I got a similar problem here (cases are included):
http://www.cfd-online.com/Forums/ope...alcontrol.html

here is another report of a similar problem too:
http://www.cfd-online.com/Forums/ope...n-freezes.html

I hope that can help solve the problem..

michael1023 December 27, 2012 05:25

Hi, hfs

sorry, I cannot help you since I am not familiar to RAS model.


All times are GMT -4. The time now is 20:19.