Hi all, I have been playin
 

Hi all,

I have been playing around with the InterFOAM solver for about 2 weeks now to simulate a rising bubble (my bubbles rise! all thanks to Sebastian Gatze's contribution to this Forum), and was toying with the idea of solving the concentration field of oxygen bubble rising in water using InterFOAM. A OpenFoam user has been sharing his work on rising bubbles in another thread using InterFOAM, and I was thinking whether it makes sense to get a concentration field around a bubble.

The first strategy that came to my mind was ..just adding the scalarTransport equation (just like how it was defined in the ScalarTransportFoam) in my InterFoam solver, after the gamma equation and velocity equation is solved.

solve
(
fvm::ddt(C)
+ fvm::div(U, C)
- fvm::laplacian(DT, C)
);
with DT = gamma*D02_liquid + (1-gamma)*DO2_air

I am however not sure how I can include a jump condition at the interface, such that CO2_liquidinterface = HenrysKoeff*C02_gasinterface. I fear that this is not possible with the VOF method since VOF doesnt track the interface per se, but just the vol. fraction of each cell, and magically reconstruct the interface. Am I right?

I recently came across a paper from Bothe et al., about direct numerical simulation of mass transfer between rising bubbles and the surrounding liquid that can be accessed through the link below.

http://chemie.uni-paderborn.de/filea...ecke/Literatur /bubblyflows.pdf

In their work with a self-built fvm code, the VOF method was used too, with the PLIC method to reconstruct the interface. The scalar transport equation was solved as follows:

Inside each phases:
dC'/dt + div(C'*u) = DT.grad(C')

whereby C' = C_liq at the liquid phase
C' = C_gas/H at the gas phase
DT (as above)

at the interphase:
C'_L = C'_G
D02_liquid*grad(C').n = H*D02_Gas*grad(C').n

Does anyone know what to include in the solver, such that the condition at the interphase is fulfilled.

Mass transfer + Interfoam
 

Hi, azman.
Could you send me your case of mass transfer coupled with interFoam?
My email is: hanniel88(at)gmail(dot)com
Replace (at) for @
And (dot) for .

For future reference: http://www.cfd-online.com/Forums/ope...one-phase.html

Hello azman,

I hope you are doing well. I would have a similar question.
I am trying to simulate a single bubble movement in a solution of water and sugar with interIsoFoam solver, OF2112. I modified the solver and coupled the density, surface tension and viscosity of solution to the concentration of sugar which is different in various parts of the domain. In order to solve the distribution of sugar (a passive scalar) in the geometry, I added a new equation to the solver as below:

fvScalarMatrix CEqn
(
fvm::ddt(C)
+ fvm::div(phi, C)
- fvm::laplacian(dc,C)
==
fvOptions(C)
);


CEqn.relax();
fvOptions.constrain(CEqn);
CEqn.solve();
fvOptions.correct(C);

Now, the problem is, sugar concentration penetrates inside the bubble which is not correct. I would like to know how can I prevent sugar entering the bubble? I would be more than happy if you share your opinion with me.