An orifice is an opening made in the side or bottom of tank, having a closed perimeter, through which the fluid may be discharged. A mouthpiece is short tube fitted to a same size circular opening provided in a tank so that fluid may be discharged through it. Orifice and mouthpiece are used to measure the rate of flow of liquid. The apparatus is designed to measure the co-efficient of discharge of orifice & mouthpiece.
The apparatus consists of a supply tank, at the side of which a universal fixture for mounting orifice or mouthpiece is attached. A centrifugal pump supplied the water to supply tank. Head over the orifice/mouthpiece is controlled by a by pass valve provided at pump discharge. A measuring tank is provided to measure the discharge. A gauge for measuring X and Y co-ordinates of jet from the orifice is provided, which is used to calculate Cv of orifice.
 Supply Tank – 0.4 X 0.3 X 0.5m height
 Orifice – 8mm and 10 mm.
(a) LID = 4
(b) L/D = 1
(c) Bordas mouthpiece.
(d) Convergent mouthpiece.
 X-Y gauge for orifice jet co-ordinates.
 Measuring tank of suitable capacity OR a calibrated water flow meter.
 Sump tank of suitable capacity.
 0.5 HP pump with valve.
A technical manual accompanies the unit.
 Flow surface 2 mtrs. X 1 mtr. X 1.5 mtrs. height.
 230 Volts, 5 Amp. Stabilized AC. Power Supply.