Water enters the pump of a steam power plant as saturated li

Water enters the pump of a steam power plant as saturated liquid at T = 20 degree C. The liquid is Isothermal pump to a pressure of 8 bags. The heat generated by the pump is 100 w. Find the work required to pump 12 kg/s of water to the higher pressure.

Solution

Ti=22^oC,

from steam table, for saturated liquid Pi=0.0265bar

Po=8bar

heat generated by pump=100W

mass flow rate m=12kg/s

m*(Po/d-Pi/d) =-q+w by Bernouli\'s theorem

=>12*(-0265*10^5/1000+8*10^5)=w-100

=>w=9668.22Watts