1. The net positive suction head required (NPSHR) by a pump may be expressed approximately as parabolic function of volume flow rate. The NPSHR for a particular pump operating function of volume flow rate. The NPSHR for particular pump operating at 1800 rpm is given as H, H + AQ (H, = 10 ft, A= 7.9 ft/cfs2). Assume the pipe system supplying pump suction consists of a reservoir, whose surface is 22 ft above the = pump centerline, a square entrance, 20 ft of 6 in cast-iron pipe, and 90elbow. Calculate the maximum flow rate at 70F for which the suction head is sufficient to operate this pump without cavitation. Use the following data, e = 0.00085 ft for cast-iron pipe, Kent=0.5, Kelbow=30f, f is friction factor vapor pressure at 70F, P=0.363 psi 1520 H 2. The inlet of a centrifugal water pump is 2.3 m above the free surface from which it draws. The inlet consists of 4 m of 5.08 cm schedule-40 steel pipe (inside diameter = 52.50 mm) and contains one long-radius elbow and one check valve. The discharge line is 5 08 cm schedule-40 steel pipe and includes two long-radius elbows and an 27 m run, The discharge is 6.3 m above the free surface. All components are regular screwed. The water temperature is 21C ( = 0.9827 x 10-3 Pa-sec). The following pump curve data are applicable. flow rate L/s 0 0.6 1.2 1.8 2.4 3.2 3.6 4.4 4.8 5.7 head m 37 36 35 34 33 31 29 25 22 17 26 22 17 (a) What is the required operating flow rate? (b) What can be said about the use of this pump in this installation? Do you recommend this pump? Justify your answer. Hint, use the attached table to find equivalent length for minor losses, and steel roughness use = 6.0 x 10-5m.