ENERGY AND EXERGY ANALYSES OF LIBR-WATER DOUBLE
SOLAR VAPOR ABSORPTION REFRIGERATION SYSTEM
COUPLED USING CONDENSER
By
P.Rajkumar & R.Shankar
Guided by
Dr.T.Srinivas
ICAER 2013

Introduction




VAR system eliminates the compressor and it is
suitable for large capacity.
Suitable for heat recovery.
Also suitable for solar thermal but more area is
required when the cooling capacity is high.
At the same time condenser rejects more heat.
ICAER 2013

Objective




Utilization of condenser heat load.
Energy and Exergy analysis of two coupled vapor
absorption refrigeration system using condenser
heat load.
Analysis of solar trough collector area and COP of
the system.
Analysis of collector area at different thermic fluid.
ICAER 2013

Double solar vapor absorption refrigeration
system coupled by using condenser
ICAER 2013

Energy equations
m1h1 m12 h12 m10 h10
c p (T21 T22 )
m17
m7 h7 m8 h8
c p (T18 T17 )
m19
m19
m5 h5 m4 h4
c p (T20 T19 )
E PRI
m4 (h5 h4 )
E SEC
m37 (h38 h37 )
m15
m1h1 m2 h2
c p (T16 T15 )
m42
m34 h34 m34 h35
c p (T43 T42 )
m32
m30 h30 m30 h31
c p (T33 T32 )
Qgen pri
m1h1 m12 h12
m10 h10
Qgen Sec
m34 h34 m27 h27 m25 h25
Qcon pri
m1 (h1 h2 )
Qcon Sec
m34 (h34
h35 )
ICAER 2013

Exergy equations
Absorber
ABS1 (m7
m17
7
m18
17
m8
18
8
)
ABS11
(m30
30
m32
32
m31
31
m33
33
)
Heat Exchanger
HEX II
(m12
m9
12
9
m10
m13
10
13
HEX III
)
(m27
27
m24
24
m25
25
m28
28
(m34
34
m42
42
m43
43
m35
35
)
Generator
GEN I
GEN II
(m21
(m25
Condenser
CON I (m1
Evaporator
EVPI (m4
25
1
4
m22
21
m16
16
22
m1
m34
m15
15
m16
m19
19
m5
34
16
5
1
m12
m27
m2
m20
27
2
)
20
)
12
)
m23
23
)
CON II
EVPII
(m37
37
m40
40
m38
38
m41
41
)
)
ICAER 2013

Material flow details of proposed design at
collector exit temperature of 110 ⁰C
State
1
2
3
4
5
6
8
Pressure
(bar)
0.056
0.056
0.056
0.012
0.012
0.012
0.012
Temperature
(⁰C)
100.00
35.00
30.50
10.00
15.00
25.00
35.00
Concentration
(kg/kg)
0.00
0.00
0.00
0.00
0.00
0.00
0.51
Mass
(kg/s)
0.27
0.27
0.27
0.27
0.27
0.27
1.00
Enthalpy
(kJ/kg)
2688.19
146.81
127.97
42.06
2528.44
2547.28
72.70
Entropy
(kJ/kgK)
8.715
0.505
0.444
0.151
8.932
8.996
0.250
Exergy
(kJ/kg)
89.69
-3.83
-4.36
-3.04
-134.56
-134.88
-1.87
9
10
12
13
15
16
21
22
23
24
25
27
28
31
34
35
36
37
38
39
42
43
0.056
0.056
0.056
0.056
1.013
1.013
1.013
1.013
1.013
0.056
0.056
0.056
0.056
0.012
0.056
0.056
0.056
0.012
0.012
0.012
1.013
1.013
35.01
61.30
100.00
64.33
30.00
90.00
110.00
90.00
80.00
35.01
60.32
80.00
51.70
35.00
80.00
35.00
30.50
10.00
15.00
25.00
30.00
35.00
0.51
0.51
0.69
0.69
0.00
0.00
0.00
0.00
0.00
0.51
0.51
0.61
0.61
0.51
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
1.00
1.00
0.73
0.73
2.72
2.72
9.51
9.51
9.51
0.55
0.55
0.46
0.46
0.55
0.09
0.09
0.09
0.09
0.09
0.09
10.62
10.62
72.71
129.79
278.00
199.98
125.89
376.97
461.19
376.97
293.15
72.71
127.68
196.47
130.93
72.70
2650.21
146.81
127.97
42.06
2528.44
2547.28
125.89
146.81
0.250
0.664
0.492
0.327
0.437
1.192
1.418
1.192
0.954
0.250
0.419
0.452
0.295
0.250
8.611
0.505
0.444
0.151
8.932
8.996
0.437
0.505
-1.89
2.91
131.18
102.53
-4.39
21.70
38.57
21.70
8.63
-1.87
2.67
61.63
43.02
-1.87
82.90
-3.83
-4.36
-3.04
-134.56
-134.88
-4.39
-3.83

Variation of primary condenser heat
rejection and the secondary cooling

Increase in collector
temperature increases
the condenser load and
secondary cooling.
ICAER 2013

Analysis of Primary COP Vs Secondary
COP

Both the primary and
secondary COP decreases
when the collector
temperature increases.
ICAER 2013

Analysis of Primary cooling and reduction
in area of the collector

Increases in collector
temperature increases the
reduction in collector area
for secondary cooling cycle
ICAER 2013

Analysis of collector area with different thermic
fluids.

Advantages



Condenser heat load is recovered.
Variable refrigerant-absorbent pair can be used in
both primary and secondary refrigeration system.
Reduction in total area of the collector.
ICAER 2013

Conclusions



Energy and Exergy analysis of the two coupled
refrigeration system is done.
Increase in COP of the system.
Reduction in area of the collector as well as total
cost of the system.
ICAER 2013

Thank You
Queries ???
ICAER 2013