This paper investigates the effect of heat exchanger allocation on overall system performance using both reverse Carnot and vapor compression refrigeration cycle models to calculate system performance and entropy generation rate. The algebraically simple constraints applied in previous studies are shown to be justifiable. The vapor compression model considers nonideal compressor performance, compressor volumetric efficiency, refrigerant properties, and throttling, in addition to mechanistic heat exchanger models. The results support the conclusions of previous studies in that maximum performance is observed when the condenser and evaporator thermal sizes are approximately equal. For air-to-air systems, this result indicates that the areas of the heat exchangers should be approximately equal. However, it is found that minimizing the entropy generation rate does not always result in the same design as maximizing the system performance unless the refrigeration capacity is fixed. Minimizing the entropy generation rate per unit capacity is found to always correspond to maximizing the coefficient of performance of refrigeration systems.

1.
Bejan
A.
,
1989
, “
Theory of Heat Transfer-Irreversible Refrigeration Plants
,”
International Journal of Heat and Mass Transfer
, Vol.
32
, No.
9
, p.
1631
1631
.
2.
Bejan
A.
,
1996
, “
Entropy Generation Minimization: The New Thermodynamics of Finite-Size Devices and Finite-Time Processes
,”
Journal of Applied Physics
, Vol.
79
, No.
3
, pp.
1191
1218
.
3.
Klein
S. A.
,
1992
, “
Design Considerations for Refrigeration Cycles
,”
International Journal of Refrigeration
, Vol.
15
, No.
3
, pp.
181
185
.
4.
Klein, S. A., and Alvarado, F. L., 1996, “EES—Engineering Equation Solver Program,” F-Chart Software, 4406 Fox Bluff Rd, Middleton, WI 53562.
5.
Radcenco
V.
,
Vargas
J. V. C.
,
Bejan
A.
, and
Lim
J. S.
,
1995
, “
Two Design Aspects of Defrosting Refrigerators
,”
International Journal of Refrigeration
, Vol.
18
, No.
2
, pp.
76
86
.
6.
Rice, C. K., 1993, “Influence of HX Size and Augumentation on Performance Potential of Mixtures in Air-to-Air Heat Pumps,” ASHRAE Transactions, Symposia Paper No. DE-93-6-4.
7.
Incropera, F. P., and DeWitt, D. P., 1990, Introduction to Heat Transfer, 2nd Edition, Wiley, New York, NY.
8.
Stoecker, W. F., and Jones, J. W., 1982, Refrigeration and Air Conditioning, McGraw-Hill, New York, NY.
9.
Wu
C.
,
Chen
L.
, and
Sun
F.
,
1996
, “
Optimisation of Steady-Flow Refrigeration Cycles
,”
Journal of Ambient Energy
, Vol.
17
, No.
4
, pp.
199
206
.
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