Question

a pump takes water from the bottom of a large tank where the pressure is 50 psi and delivers it through a hose to a nozzle that is 50ft above the bottom of the tank at a rate of 100 ibm/s. the water exits the nozzle into the atmosphere at a velocity of 70ft/s.if a 10hp motor is required to drive the pump which is 75% efficient, find:the friction loss in the pump

Answer 1

The friction loss in the pump is 442.12 lb*ft/slug

Step-by-step explanation:

the efficiency is

`n=(W_(shaft)-W_(loss))/(W_(shaft) ) =0.75\\W_(shaft)=(pump-power)/(flow-rate)`

pump power = 10 hp = 5500 lb*ft*s⁻¹

flow rate = 100 lbm/s = 3.11 slug*s⁻¹

`W_(shaft) =(5500)/(3.11) =1768.48 lbft/slug`

Clearing Wloss in equation of efficiency

`0.75=(1768.48-W_(loss) )/(1768.48) \\W_(loss) =442.12lbft/slug`