bubbly flow
 

Hello,

I am calculating euler-euler flow (air-bubbles in water tank). I have bubbles with diameter of 50mm while the tank is about 2.5 m in diameter. Someone advised me to use a coarse meash that is abou 100mm x100 mmm as cell cize. I still did not get why?
Now i tried a denser mesh and I observe a significant increase in the "average" rising velocity of aboz factor 2.
Normally I would try an even denser mesh and see if the observed values converge and use this mesh. But how to find a right coarse mesh?

Hopefully some can help me on this discussion.

Thanks in advance!

i want some tutorials on modeling bubbly flow in fluent
and thank you