Diogo Martinho

Ok, thanks. 
So, let's say we are simulation water-oil-hydrogen, and they are defined as three phases where, water will be the primary phase and the remaining secondary phases. Will I have a continuity equation for the oil, another for the hydrogen, a continuity equation for the pressure (I am not entirely sure if I understood this equation though) and finally, the water will be 1-sumover_all_secondary_phases(volume fraction)?