FLOW MEASURING DEVICES
There are several devices commonly used for flow measurement namely: orifice meter, venturi meter, Pitot tube, nozzle, variable area meter, water meter, and measuring tank. Some of these are employed on this test Apparatus.
3.1 Orifice Meter
when an orifice plate is placed in a pipe, the velocity of water flowing through the pipe at or immediately after the orifice is higher than velocity before the orifice. At the same time, static pressure before the orifice is higher than at the orifice. The pressure difference i measured by a manometer. In this case, applying Bernoulli's equation between point l and point 2 gives: