Reference no: EM131179890

An orifice plate is to be used in conjunction with a differential pressure transmitter to measure the flow rate of water in a 0.15 m diameter pipe. The maximum flow rate is 50 m³ h^-1, the density of water is 10³ kg m^-3 and the viscosity is 10^-3 Pa s.

(a) Explain why an orifice plate meter is suitable for this application.

(b) Estimate the required orifice plate hole diameter if the transmitter has an input range of 0 to 1.25 x 10⁴ Pa.

A turbine flowmeter consists of an assembly of four ferromagnetic blades rotating at an angular velocity ω rad s^-1 given by:
ω= 4.5 x 10⁴ Q

where Q m³ s^-1 is the volume flow rate of the fluid. The total flux N linked by the coil of the magnetic transducer is given by:

N= 3.75 + 0.88 cos 4θ milliwebers

where θ is the angle between the blade assembly and the transducer. The range of the flow-meter is 0.15 x 10^-3 to 3.15 x 10^-3 m³ s^-1.

Calculate the amplitude and frequency of the transducer output signal at minimum and maximum flows.