Page 241 - Low Temperature Energy Systems with Applications of Renewable Energy

228 Low-Temperature Energy Systems with Applications of Renewable Energy

First we write out the equations for the rate of exergy at each of the state points
shown in Figs. 6.3 and 6.4.

_
E R ¼ _ m R ðh R T 0 s R e 0 Þ (6.1)
_
E 1 ¼ _ m R ðh 1 T 0 s 1 e 0 Þ (6.2)
_
E 2 ¼ _ m R x 1 ðh 1g T 0 s 1g e 0 Þ (6.3)
_
E 3 ¼ _ m R x 1 ðh 3 T 0 s 3 e 0 Þ (6.4)
_
E 4 ¼ 0 (6.5)

_
E 5 ¼ _ m R ð1 x 1 Þðh 1f T 0 s 1f e 0 Þ (6.6)
_
E 6 ¼ _ m R ð1 x 1 Þð1 yÞðh 1f T 0 s 1f e 0 Þ (6.7)
_
E 7 ¼ _ m R ð1 x 1 Þyðh 1f T 0 s 1f e 0 Þ (6.8)
_
E 8 ¼ _ m R ð1 x 1 Þyðh 8 T 0 s 8 e 0 Þ (6.9)
_
E 9 ¼ 0 (6.10)
_
E 10 ¼ _ m 9 ðh 10 T 0 s 10 e 0 Þ (6.11)

_
E 11 ¼ _ m 9 ðh 11 T 0 s 11 e 0 Þ (6.12)
_
E 12 ¼ _ m 9 ðh 12 T 0 s 12 e 0 Þ (6.13)
_
E 13 ¼ 0 (6.14)
_
E 14 ¼ _ m 13 ðh 14 T 0 s 14 e 0 Þ (6.15)
_
E 15 ¼ _ m 13 ðh 15 T 0 s 15 e 0 Þ (6.16)

where

e 0 ¼ h 0 T 0 s 0 (6.17)

x 1 ¼ _ m 2 = _ m 1 ¼ðh R h 1f Þ=ðh 1g h 1f Þ (6.18)

s 1 ¼ s 1f þ x 1 ðs 1g s 1f Þ (6.19)