After the installation of the orifice meter of Example 8.4, the manometer reading at a definite constant flow rate is 45 mm. Calculate the flow through the line in m³/h measured at 15°C.

Exercise 8.4

An orifice meter with flange taps is to be installed in a 100-mm line to measure the flow of water. The maximum flow rate is expected to be 50 m³/h at 15°C. The manometer used to measure the differential pressure is to be filled with mercury, and water is to fill the leads above the surfaces of the mercury. The water temperature will be 15°C throughout.

(a) If the maximum manometer reading is to be 1.25 m, what diameter, to the nearest millimeter, should be specified for the orifice?

(b) What will be the power to operate the meter at full load?