Discharge Coefficients
For each type of nozzle, a graph of Discharge Coefficient vs. ReD or d/D is shown. Each graph is followed by the equation used to form the graph. The equations are from ISO (1991).

ISA 1932 Nozzle Discharge Coefficient Equation:
C = 0.9900 - 0.2262(d/D)4.1 - [0.00175(d/D)2 - 0.0033(d/D)4.15][106/ReD]1.15
Valid for: 5 cm <= D <= 50 cm
and 0.3 <= d/D < 0.44 having 7x104 <= ReD <= 107
and 0.44 <= d/D <= 0.8 having 2x104 <= ReD <= 107
and k/D <= 3.8 x10-4 generally for all d/D

Long Radius Nozzle Discharge Coefficient Equation:
C = 0.9965 - 0.00653[(106)(d/D)/ReD]0.5
Valid for: 0.2 <= d/D <= 0.8, 104 <= ReD <= 107, 5 cm <= D <= 63 cm
and k/D <= 10-3 generally.


Venturi Nozzle Discharge Coefficient Equation:
C = 0.9858 - 0.196(d/D)4.5
Valid for: 0.316 <= d/D <= 0.775, 1.5x105 <= ReD <= 2x106,
6.5 cm <= D <= 50 cm, d >= 5 cm, and k/D <= 3.8x10-4 generally