Question

A pump moves water horizontally at a rate of 0.02 m3/s. Upstream of the pump where the pipe diameter is 90 mm, the pressure is 120 kPa. Downstream of the pump where the pipe diameter is 30 mm, the pressure is 400 kPa. If the loss in energy across the pump due to fluid friction effects is 170 N.m/kg, determine the hydraulic efficiency of the pump.

Answer 1

Answer:

the efficiency of hydralic is 79.88%

Explanation:

convert mm to m

1mm = (1/1000)m

diameter of pipe upsteam

d₁= 90mm= 0.09m

diameter of pipe downsteam

d₂= 30mm = 0.03m

finding velocity of upsteam

recall Q=A₁V₁

V₁=Q/A₁

V₁=3.14m/s

velocity of downsteam

V₂= Q/A₂

V₂= 28.29m/s

mass flow rate

m= ρQ

ρ is the density of water

m = 1000× 0.02

m= 20kg/s

the efficiency of hydralic is 79.88%