CFD Online Discussion Forums

CFD Online Discussion Forums (
-   OpenFOAM (
-   -   Alphaeqn in bubble Foam (

rans2009 October 5, 2009 04:31

Alphaeqn in bubble Foam
Hi friends,
You can find this part of program in alphaEqn of bubbleFoam
/* fvScalarMatrix betaEqn
+ fvm::div(phi, beta, scheme)
+ fvm::div(-fvc::flux(phir, scalar(1) - beta, scheme), beta, scheme)

alpha = 0.5*(scalar(1) + sqr(scalar(1) - beta) - sqr(scalar(1) - alpha));

I am again asking questions about volume fractions in bubble column tutorial,
1) whats this beta equation,
2) is it volume intialzation file of water or other fluid???,
3) Whats the equation in block font represent is it correction factor for alpha ?

Can anyone explain me this doubt,
thanks in advance,

Anticipating for your kind reply,

sachin October 22, 2009 10:14

I doubt if that code runs because /* .......... */
in the end we have beta=1-alpha...still we there might have be something else to it
still i am not sure somebody else might help

good luck

rans2009 October 23, 2009 05:25

Thanks Sachin,
yes as you told, beta equation doesnt work, beta takes the value (1-alpha),
I had one more doubt, velocity given to water(Ub) in UEqn.H file does not work, I mean we cannot see any motion of water, except gase flow is seen,
can you see this please,
thank you in advance,

sachin October 23, 2009 09:38

Please could you explain the case, I havent used these solvers

best wishes

All times are GMT -4. The time now is 18:09.