[JalalKh]

Hello
my project is:
The bubble column modeled in the simulation is semi-batch where air flows continuously through a batch layer of water-oil
The distributor inlet at the bottom of the vessel has only air flowing through it (air volume fraction =1).
,is the mass transfer really needed to completely simulate the flotation of oil?
if it needed,any model of mass transfer must i used, i mean Specified Mass Transfer or phase change or Cavitation?
Second question:
in fluid pair models just the two pairs
air-water
kerosene-water
appears in the tab, why the pair (air-kerosene) does not appear?
Thank you for help.