[gnut1989]

Hello all,

I have some problems when i try to run pisoFoam (i want to use RANS to solve it) to solve elbow problem. You can see in the attached file the geometry and meshing

I can not calculate the values of k and epsilon to input into OpenFOAM (file k & epsilon in the 0 directory).
Can you help me to solve this problem and run it.

[derekm]

Originally Posted by gnut1989

Hello all,

I have some problems when i try to run pisoFoam (i want to use RANS to solve it) to solve elbow problem. You can see in the attached file the geometry and meshing

I can not calculate the values of k and epsilon to input into OpenFOAM (file k & epsilon in the 0 directory).
Can you help me to solve this problem and run it.

Have you looked at page 40 in the OpenFOAM userguide.

[gnut1989]

Originally Posted by derekm

Have you looked at page 40 in the OpenFOAM userguide.

Thanks Derekm very much!
I've seen it and tried to calculate.
The result for k = 1/2 (U'x^2 + U'y^2 + U'z^2) = 1/2 (0.04 + 1) = 0.52 m2 s-2
is it right or wrong?
You can help me calculate the value of epsilon????

Thanks again and hope that you merry christmas!!!!!

Duong Tung

[Alhasan]

Hey Duong Tung,

It is straight forward have a look at this and calculate your K, E, W etc.

http://www.cfd-online.com/Wiki/Turbu...ary_conditions

Happy simulation all the best,

Hasan K.J

[gnut1989]

Originally Posted by Alhasan

Hey Duong Tung,

It is straight forward have a look at this and calculate your K, E, W etc.

http://www.cfd-online.com/Wiki/Turbu...ary_conditions

Happy simulation all the best,

Hasan K.J

Hello Hasan,

Thanks a lot for your suggestion! I have looked at the link and calculated in the attached excel file. Could you please check it for me?

I am still confused that I have two inlets (1 & 2) so i have to calculate two values for epsilon. Is it right or wrong???? And after inputting the value of k and epsilon into k & epsilon files at 0 directory in OpenFoam, I can run this problem????

Please help me to check it. Thank you very much!!!

[Alhasan]

Hey Duong Tung,

It looks like reasonable values to me, take it as a guidance value and run your simulations when you compare it with the experimental data you will get a better idea of where you stand !!

All the best,
Hasan K.J