The discharge of a reciprocating pump is given by the following formula
Qt = A L N
where Qt is the theoretical discharge in m3A is the Area of the piston in m2
L is the length of the stroke in m
N is the number of the revolutions of the crank per second (rps)
Coefficient of Discharge
The Coefficient of Discharge of a reciprocating pump is the ratio of the actual discharge to the theoretical discharge.
Cd = Qa / Qt
Where
Cd is the Coefficient of Discharge
Qa is the actual discharge in m3
Qt is the theoretical discharge in m3
Slip in a Reciprocating pumps
Slip in a Reciprocating pump is the difference between the theoretical discharge and the actual discharge.
Slip = Qt - Qa