The 4 Cases considered for HYD Fluid Properties

Case 1:	P > Psat	there is no vapor and all air/gas is dissolved
Case 2:	PHvap< P < Psat	there is no vapor and part of the air/gas is dissolved and part free
Case 3:	PLvap < P < PHvap	there is some vapor and ALL the air/gas is free
Case 4:	P < PLvap	there is vapor and air/gas but NO LIQUID

That can be schematized on the following picture:

Figure 3: air/gas release and cavitation process