Spray Discharge CD (Discharge Coefficient)

The pressure drop across a spray discharge which uses a discharge coefficient is discussed here. The mass flow rate through a restriction is given as follows:

The pressure drop across a discharging restriction is given as:

Combining the two yields:

or

This equation is used for spray discharge junctions in AFT Fathom, with the ΔP being the difference between stagnation pressure at the spray discharge inlet and the exit pressure specified for the junction.