A large elevated tank (Tank 1) is being used to supply water at 60°F to two tanks at a lower elevation (Tanks 2 and 3) as shown in Figure P4.28. All pipes are 5-nom sch 40 commercial steel. The straight lengths of the piping in Sections AB, BC, and BD are indicated in the figure. The elevation of the free surface of the water in each tank is also indicated in the figure.

a. Determine the volumetric flow rate (gpm) delivered to each lower tank (Tanks 2 and 3) for the conditions shown.

b. The globe valve in this system is used for flow control. Determine the effect of partially closing the globe valve by constructing two plots; (1) the total volumetric flow from Tank 1, and (2) the volumetric flow delivered to each of the lower tanks (Tanks 2 and 3). Show each of these volume flows as a function of the globe valve constant, C, in the resistance coefficient equation,

where K3K is the K-value for a wide opened globe valve calculated using the 3K method and C varies between 1 (wide opened) and 100 (partially closed).

Transcribed Image Text:

Kglobe = CK 3K