A venturi meter is a device that uses a constriction in a flow system to measure the velocity of flow. Figure 6.17 illustrates one type of design. If the main pipe section is a standard hydraulic copper tube having a 100-mm outside diameter × 3.5-mm-wall thickness, compute the volume flow rate when the velocity there is 3.0 m/s. Then, for that volume flow rate, specify the required size of the throat section that would make the velocity there at least 15.0 m/s.

Main pipe Main pipe Throat section section section 3 . Flow a, - 21 + 2 100-mm OD x a, -5 - 15 3.5-mm wall copper tube - Manometer