Answer to Question #174112 in Mechanical Engineering for Jansen

Question

There are received 68,000 kg/h of steam by an ideal regenerative engine, having only one heater, of which the heater receives 15,400 kg/h; the condenser receives the re- mainder at 0.007 MPa. If the heater pressure is 0.96 MPa, find the state (quality or °SH) of the steam (a) at the heater entrance and (b) at the condenser entrance

Answer 1

Intial pressure of heater = 0.96 MPa, Inital heat receives by heater=15400 kg/h

Pressure of condenser=0.007 MPa

Now steam quality at 0.96 MPa

S₁= S₂=6.599

(a) at the heater entrance it is saturated steam

At 0.007Mpa

S_f1= 0.559 KJ/Kg h , S_fg=7.716 KJ/kgh

we know that

S=S_f + xS_fg

$S_2= S_{f2} + x S_{fg2}$

$6.599= 0.559 + x\times 7.716$

x= 0.783

(b) qualtiy of steam will be 78.3 % at condenser entrance