This preview shows pages 1–3. Sign up to view the full content.
Example 81
In an ideal Rankine cycle with steam as the working fluid,
saturated vapor enters the turbine at 8 MPa and saturated
liquid exits the condenser at 0.008 MPa. The net
power
output of the cycle is 100 MW. Sketch the cycle on a
Ts
diagram and find:
a) quality at the turbine exit
b) mass flow rate of the steam
c) heat added in the boiler
d) cycle efficiency
Note: number your states as in this lecture to avoid
confusion.
Solution:
For the turbine:
34
s
s
=
3
kJ
entropy(steam,
1,
8000)
5.74
kg K
sx
P
==
=
=
⋅
()
T
Wm
h
h
=−
±
±
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document 3
kJ
enthalpy(steam,
1,
8000)
2758
kg
hx
P
==
=
=
4
kJ
enthalpy(steam,
5.74,
8)
1794
kg
hs
P
=
=
4
quality(steam,
5.74,
8)
0.675
xs
P
=
=
For the pump:
( )
21
P
Wm
v
P
P
=−
±
±
3
m
volume(steam,
0,
8)
0.001008
kg
vx
P
=
=
( )
34
net
T
P
WW
W
m
h
h
=−=
−
±±
±
±
()
( )
net
h
h
m
v
P
P
−
−
±
6
36
10 W
kJ 1000 J
m
10 Pa
100 MW
2758 1794
0.001
8
0.008 MPa
1 MW
kg
1 kJ
kg
1 MPa
m
⎛⎞
⎡
⎤
−
−
⎜⎟
⎢⎥
⎝⎠
⎣
⎦
±
kg
104.7
s
m
=
±
To find pump work:
( )
P
v
P
P
±
±
kg
m
10 Pa
104.7
This is the end of the preview. Sign up
to
access the rest of the document.
This homework help was uploaded on 04/07/2008 for the course MANE 4010 taught by Professor Kaminski during the Spring '08 term at Rensselaer Polytechnic Institute.
 Spring '08
 Kaminski

Click to edit the document details