Fluent considers each Eularian phase as a continuum - that's why individual bubbles cannot be a seperate phase (other than in the Euler-Lagrange approach). This is also not be possible because, in the Euler-Euler model, the momentum equations are solved separately for each phase, i.e. you would have to solve thousands or millions of momentum equations for a bubbled tank. The numerical details are explained in the theory guide available at http://148.204.81.206/Ansys/150/ANSYS%20Fluent%20Theory%20Guide.pdf (chapter 17).  How many Eulerian phases you define mainly depends on how many different fluids (liquid/gases) are present and if there is any momentum exchange between them. For example, if you have a well-mixed multicomponent liquid mixture (solute and solvent) you can treat it as a single Eulerian phase. A gas-liquid system is normally treated as a two-phase system (with air in the gaseous phase and water in the liquid phase, for example). This, presumably, is also the case for your model - CO2, N2 and vapor in the gaseous phase and H2Oliquid, C1, C2 and C3 in the liquid phase (given that only water evaporates/condensates). If you want to calculate the distribution of the individual components you have to include the species transport model and you need to define mass transfer models in addition in order to account for evaporation and condensation. 

Hope this helps. 

Regards, 

Stephan

thank you for your help, but there is one question, water liquid is not solution in organic compounds like C1,C2,C3 so can we define phases as gaseous (water vapor, C1,C2,C3,N2,CO2) with bubbles in liquid, and organic liquid phase(C1,C2,C3) and water liquid phase, totally 3 phases?

it is noted that maximum temperature is 100 centigrade

Of course you can define three phases if the two liquid phases are immiscible. Be aware of using a characteristic particle (bubble/droplet) diameter, which is representiive for your system. Alternatively, a population balance model could be used, but this makes calculations much more difficult and requires information about the size distribution. Depending on the pressure it may be required to integrate boiling models if the maximum temperature is 100 °C. Some details on the available models are explained in section 17.7.5 of the Fluent theory guide. Unfortunately, I never had to use those models and, thus, I don't know any details about the numerics and/or their stability.

Regards, 

Stephan

Hello, I'm working with propane leak where steam propane leaks into the environment with liquid propane drops, if I have an interest in the condensation evaporation of propane, what should I do, should I use 2 phases in the Eulerian approach? In my understanding of the dispersed phase would be the air in the environment?