Question 2 a) The pipes of diameter D and d of equal length L are considered....

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Question 2 a) The pipes of diameter D and d of equal length L are considered. If the pipes are arranged in parallel, the loss of head for either pipe for a flow of Q is h. If the pipes are arranged in series and the same quantity Q flows through them, the loss of head is H. If d = 0.5 D, what account for head loss difference in series connection. Find the percentage of total flow through each pipe when placed in parallel and the ratio of H to h neglecting minor losses and assuming friction co- efficient to be constant. CR (8) b) Compute the radius b for the annulus of Water at 20°C flows, at the same flow rate Q = 9.4x 10-4 m³/s, through two ducts, one a round pipe, and one an annulus, as shown. The cross-section area A of each duct is identical, and each has walls of commercial steel. Both are the same length. In the cross-sections shown, R = 15 mm and a = 25 mm. Compare head loss per unit length for the two ducts, first using the hydraulic diameter and second using the 'effective diameter' concept. If the losses are different, why? Which duct is more 'efficient'? Why? EV(5) c) You wish to water your garden with 100 ft of 5/8-in-diameter hose whose 0.011 in. What will be the delivery, in ft3/s, if the gage pressure If there is no nozzle (just an open hose exit), what exit jet will carry? roughness is at the faucet is 60 lbf/in²? is the maximum horizontal distance the water jet Hose 45° a X=V^2/g EV(7) d) The shower head in Fig. P6.142 delivers water at 50BC. An orifice-type flow reducer is to be installed. The upstream pressure is constant at 400 kPa. What flow rate, in gal/min, results without the reducer? What reducer orifice diameter would decrease the flow by 40 percent? CR(5) Question 2 a) The pipes of diameter D and d of equal length L are considered. If the pipes are arranged in parallel, the loss of head for either pipe for a flow of Q is h. If the pipes are arranged in series and the same quantity Q flows through them, the loss of head is H. If d = 0.5 D, what account for head loss difference in series connection. Find the percentage of total flow through each pipe when placed in parallel and the ratio of H to h neglecting minor losses and assuming friction co- efficient to be constant. CR (8) b) Compute the radius b for the annulus of Water at 20°C flows, at the same flow rate Q = 9.4x 10-4 m³/s, through two ducts, one a round pipe, and one an annulus, as shown. The cross-section area A of each duct is identical, and each has walls of commercial steel. Both are the same length. In the cross-sections shown, R = 15 mm and a = 25 mm. Compare head loss per unit length for the two ducts, first using the hydraulic diameter and second using the 'effective diameter' concept. If the losses are different, why? Which duct is more 'efficient'? Why? EV(5) c) You wish to water your garden with 100 ft of 5/8-in-diameter hose whose 0.011 in. What will be the delivery, in ft3/s, if the gage pressure If there is no nozzle (just an open hose exit), what exit jet will carry? roughness is at the faucet is 60 lbf/in²? is the maximum horizontal distance the water jet Hose 45° a X=V^2/g EV(7) d) The shower head in Fig. P6.142 delivers water at 50BC. An orifice-type flow reducer is to be installed. The upstream pressure is constant at 400 kPa. What flow rate, in gal/min, results without the reducer? What reducer orifice diameter would decrease the flow by 40 percent? CR(5)