... Q
r
Btu/lb
ϭϪ
H
7
)(1
Ϫ
m
1
Ϫ
(H
6
Ј
m
2
Ϫ
m
3
)
ϭ
(938.4
Ϫ
47.1)(0.6277)
ϭ
55 9 .5 Btu (59 0.3 kJ). Then W
e
Ϫ
W
p
ϭ
Q
a
Ϫ
Q
r
ϭ
969.0
Ϫ
55 9 .5
ϭ
409 .5 Btu (432.0 kJ).
Compare this with W
e
Ϫ
W
p
computed earlier, or 4 15. 9
Ϫ
7.0
ϭ
408.9 Btu
(431.4 kJ), or a difference of ... Btu/lb per pound of
throttle flow. Then 1372.2m
1
ϩ
( 355 .4
ϩ
1.7)(1
Ϫ
m
1
)
ϭ
50 0.8; m
1
ϭ
0.1416 lb/...
... Or, U
ϭ
58 5(0. 95)
ϭ
55 5. Then x
ϭ
0.812 (55 5/ 50 0)
ϭ
0.90; e
x
ϭ
2.7183
0.90
ϭ
2.46; t
2
ϭ
101.1
Ϫ
(101.1
Ϫ
85/ 2.46)
ϭ
94.6
Њ
F (34.8
Њ
C).
Check
⌬
t
ϭ
t
s
Ϫ
t
2
ϭ
101.1
Ϫ
94.6
ϭ
6 .5
Њ
F (3.6
Њ
C), ... greater than 5
Њ
F
(2.8
Њ
C). The cooling-water flow rate, gal /min
ϭ
950 ( 25, 000)/ [50 0(94.6
Ϫ
85) ]
ϭ
4 950 gal / min (312.3 L /s). Then A
ϭ
0.812(4 950 )
ϭ
4020 ft
2
(373...
... h
( 454 ,000 kg /h) of steam at initial conditions of 1800 psia (12,402 kPa) and 1 050
Њ
F
(56 5.6
Њ
C). At exit from the cylinder the steam has a pressure of 50 0 psia (34 45
kPa) and a temperature of ... temperature
ϭ
150 .5
Њ
F ( 65. 8
Њ
C) exit temperature
ϩ
5
Њ
F (2.8
Њ
C) terminal difference
ϭ
155 .5
Њ
F
(68.6
Њ
C). From the saturation-temperature steam table, the pres...