Question

Example 2.2 Pumping n Pentane 65 Example 2.2-Pumping nPentane Vent Storage tank 40 ft Flow Vent Supply tank 4.5 ft Punp n? Fig. E2.2 Pumping n-pentane. Fig. E2.2 shows an arrangement for pumping n-pentane ( 39.3 lbin/fts) at 25 C from one tank to another, through a vertical distance of 40 ft. All piping is 3-in. I.D. Assume that the overall frictional losses in the pipes are given (by methods to be described in Chapter 3) by: For simplicity, however, you may ignore friction in the short length of pipe leading to the pump inlet. Also, the pump and its motor have a combined efficiency of 75%. If the mean velocity u", is 25 ft/s, determine the following: (a) The power required to drive the pump. (b) The pressure at the inlet of the pump, and compare it with 10.3 psia, which is the vapor pressure of n-pentane at 25 °C. (c) The pressure at the pump exit. Solution The cross-sectional area of the pipe and the mass flow rate are: (E2.2.2) 40 (12 2 Ib (E22:3) 48.2 39.3x 25x 0.0491 m-pren,

i cannot understand (E2.2.2) (3/12)^2...

Answer 1

kindly rate

Diameter d pip e in 3inch Gy relation behoeen inch and inch feet 12 ↑ 3inch 3 ft 12 Area 2 = 0.0491 ft2