Consider the Rankine cycle shown P2 p5 07 MPa p4 0008 Moa

Consider the Rankine cycle shown. P_2 = p_5 = 0.7 MPa p_4 = 0.008 Moa. Pump 1 operates isentropically (isothermally). The isentropic of the high-pressure turbine is 0.90 Determine y.

Solution

given initial temperature is 480 degree centigrade

initial pressure is 8.0 mpa

from steam bles we have to find the h1 and s1

from interpolation we will get

h1=3348.4kj/kg

s1=6.65kj/kg k

given p2=0.7 mpa

given that pump operates isoentropically

therfore s2=s1

s2=6.65kj/kg k

sf=1.99

to find the quality of the mixture we have to find x2 at 2

x2=(s2-sf)/sfg

s2=(6.65-1.99)/4.7

=0.9

iso entropic efficiency is given as

isoentropic work done /actual work done

by substituting the appropraite values we will get the required value of y which is the amount of heat regenerated