Can anyone explain the physics behind the following ..

When I did a simulation of a bubble column with bubbles specified at 4 mm, the vapour fraction in the column was about 0.96. When I increased the bubble size to 10 mm, the vapour fraction went down to 0.45.

Is the buoyancy force the difference. I used k-epsilon.

Thanks in advance, Sally.

Hi,

I am tackling the same problem here too.

Could you please tell me as to how you created the bubble in cfx-pre. did u use a CEL or did u create 2 domains(by loading two meshes, one for the bubble and one for the column?)

Cheers, Nick

i have made a buble column of 1 inch dia. what should be nesesary heiht of water in my column & why