Experimental performance analysis and optimization of a direct expansion solar-assisted heat pump water heater

In this study, a direct expansion solar-assisted heat pump water heater (DX-SAHPWH) with rated input power 750W was tested and analyzed. Through experimental research in spring and thermodynamics analysis about the system performance, some suggestions for the system optimization are proposed. Then, a small-type DX-SAHPWH with rated input power 400W was built, tested and analyzed. Through exergy analysis for each component of DX-SAHPWH (A) and (B), it can be seen that the highest exergy loss occurs in the compressor and collector/evaporator, followed by the condenser and expansion valve, respectively. Furthermore, some methods are suggested to improve the performance of each component, especially the collector/evaporator. A methodology for the design optimization of the collector/evaporator was introduced and applied. In order to maintain a proper matching between the heat pumping capacity of the compressor and the evaporative capacity of the collector/evaporator under widely varying ambient conditions, the electronic expansion valve and variable frequency compressor are suggested to be utilized for the DX-SAHPWH.

[1]  William A. Beckman,et al.  Solar heat pump systems with refrigerant-filled collectors , 1983 .

[2]  Noboru Kojima.  Experimental Development of a Torsion Arc Blade Type Horizontal Axis Windmil , 1996 .

[3]  J. MacArthur,et al.  Theoretical analysis of the dynamic interactions of vapor compression heat pumps , 1984 .

[4]  T. Freeman,et al.  Performance of combined solar-heat pump systems , 1979 .

[5]  Ruzhu Wang,et al.  Experimental study on solar assisted heat pump system for heat supply , 2003 .

[6]  Onder Ozgener,et al.  Experimental performance analysis of a solar assisted ground-source heat pump greenhouse heating system , 2005 .

[7]  S. Chaturvedi,et al.  Thermal performance of a variable capacity direct expansion solar-assisted heat pump , 1998 .

[8]  Sushil K. Chaturvedi,et al.  Solar collector as heat pump evaporator , 1979 .

[9]  Sushil K. Chaturvedi,et al.  Thermodynamic analysis of two-component, two-phase flow in solar collectors with application to a direct-expansion solar-assisted heat pump , 1999 .

[10]  Richard G. Morgan.  Solar assisted heat pump , 1982 .

[11]  Bin-Juine Huang,et al.  Integral-type solar-assisted heat pump water heater , 1999 .

[12]  J. Cervantes,et al.  Experiments on a solar-assisted heat pump and an exergy analysis of the system , 2002 .

[13]  S. Ito,et al.  PERFORMANCE OF A HEAT PUMP USING DIRECT EXPANSION SOLAR COLLECTORS 1 Paper presented at the ISES Sol , 1999 .

[14]  Sushil K. Chaturvedi,et al.  Transient simulation of a capacity-modulated, direct-expansion, solar-assisted heat pump , 1987 .

[15]  Petros Axaopoulos,et al.  Experimental comparison of a solar-assisted heat pump vs. a conventional thermosyphon solar system , 1998 .

[16]  M. Picon Nunez,et al.  Exergy analysis and optimization of a solar-assisted heat pump , 1998 .

[17]  W. Swinbank.  Long‐wave radiation from clear skies , 1963 .

[18]  Bin-Juine Huang,et al.  Performance characteristics of integral type solar-assisted heat pump , 2001 .

[19]  K. I. Krakow,et al.  A solar source heat pump with refrigerant-cooled solar collectors for cold climates☆ , 1982 .

[20]  Mohammad Nurul Alam Hawlader,et al.  The performance of a solar assisted heat pump water heating system , 2001 .

[21]  S. Ito,et al.  Studies of Heat Pumps Using Direct Expansion Type Solar Collectors , 2005 .

[22]  Graham L. Morrison.  Simulation of packaged solar heat-pump water heaters , 1994 .

[23]  S. Chaturvedi,et al.  Thermal performance of a direct expansion solar-assisted heat pump , 1984 .

[24]  Bin-Juine Huang,et al.  Performance analysis of a solar-assisted heat pump water heater , 2003 .

[25]  Ruzhu Wang,et al.  Study on a direct‐expansion solar‐assisted heat pump water heating system , 2003 .