Question

Diaphragm valves are a common type of industrial valve used to regulate flow. This type of valve has a flexible disk that can be pressed toward the valve seat to control the flow. One advantage of diaphragm valves is that the diaphragm separates the internal workings of the valve from the fluid flow so it is good for use with corrosive liquids or fluids that must be free from contamination, such as in the pharmaceutical industry. a) Determine the volumetric flow rate of water (in m³/s) discharging through a 0.2 m diaphragm valve to the atmosphere when the upstream pressure is 236 kPa and when the valve is wide open, 3/4 open, 1/2 open, and 1/4 open (use the posted loss coefficients from Perry's Handbook). b) Plot the volumetric flow rate against the fraction open (a hand plot is fine).

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