The impact of fouling on performance of a vapor compression refrigeration system with integrated mechanical sub-cooling system

Performance characteristics due to fouling in a vapor compression cycle with integrated mechanical sub-cooling are investigated for various applications. Considering the first set of refrigerants i.e. R134a, R410A and R407C, from a first law standpoint, the COP indicates that R134a always performs better unless only the evaporator is being fouled. From a second law standpoint, the second-law efficiency indicates that R134a performs the best in all cases. Considering the second set of refrigerants i.e. R717, R404A and R290, the COP indicates that R717 always performs better unless only the evaporator is being fouled; however, the second-law efficiency indicates that R717 performs the best in all cases. Furthermore, the performance degradation due to fouling of the evaporator always has a larger effect on cooling load capacity while the performance degradation of the condenser always has an overall larger effect on the sub-cooler compressor power requirement as well as the COP of the system. In light of the data generated, a new performance degradation law, presented earlier, is shown to be applicable for this system as well that can reduce the amount of experimentation and help predict relevant quantities of the refrigeration system.

[1]  Mark Modera,et al.  Efficient Thermal Energy Distribution in Commercial Buildings , 1999 .

[2]  William W. Nazaroff,et al.  Modeling particle deposition on HVAC heat exchangers , 2002 .

[3]  J E Braun,et al.  Impact of fouling and cleaning on plate fin and spine fin heat exchanger performance. , 2005 .

[4]  Eckhard A. Groll,et al.  Air-side particulate fouling of microchannel heat exchangers: Experimental comparison of air-side pressure drop and heat transfer with plate-fin heat exchanger , 2011 .

[5]  Lingen Chen,et al.  Optimal allocation of heat-exchanger area for refrigeration and air-conditioning plants , 2004 .

[6]  Rodrigo Llopis,et al.  Performance evaluation of R404A and R507A refrigerant mixtures in an experimental double-stage vapour compression plant , 2010 .

[7]  W. F. Stoecker,et al.  Refrigeration and air conditioning , 1958 .

[8]  James M. Calm,et al.  Emissions and environmental impacts from air-conditioning and refrigeration systems , 2002 .

[9]  Luca Cecchinato,et al.  Design and experimental analysis of a carbon dioxide transcritical chiller for commercial refrigeration , 2008 .

[10]  M.S.J. Hashmi,et al.  Super-subcooling with R12 and R22 refrigeration plants using reciprocating compressors , 1993 .

[11]  Syed M. Zubair,et al.  Performance degradation of a vapor compression refrigeration system under fouled conditions , 2011 .

[12]  J. W. Ramsey,et al.  Thermal Environmental Engineering , 1970 .

[13]  D. P. Sekulic,et al.  Fundamentals of Heat Exchanger Design , 2003 .

[14]  Guoliang Ding,et al.  Effects of biofouling on air-side heat transfer and pressure drop for finned tube heat exchangers , 2009 .

[15]  Unfccc.  Kyoto Protocol to the United Nations Framework Convention on Climate Change , 1997 .

[16]  S. K. Fischer,et al.  TEWI Analysis: Its Utility, Its Shortcomings, and Its Results , 1999 .

[17]  Liang Yang,et al.  On subcooler design for integrated two-temperature supermarket refrigeration system , 2011 .

[18]  James E. Braun,et al.  The impact of evaporator fouling and filtration on the performance of packaged air conditioners , 2007 .

[19]  Ramón Cabello,et al.  Comparative evaluation of the intermediate systems employed in two-stage refrigeration cycles driven by compound compressors , 2010 .

[20]  Syed M. Zubair,et al.  Design and rating of an integrated mechanical-subcooling vapor-compression refrigeration system , 2000 .

[21]  Syed M. Zubair,et al.  Mechanical subcooling improves supermarket refrigeration performance , 1988 .

[22]  Ahmed Hamza H. Ali,et al.  Evaporator Air-Side Fouling: Effect on Performance of Room Air Conditioners and Impact on Indoor Air Quality , 2008 .

[23]  Syed M. Zubair,et al.  Thermodynamics of a vapor-compression refrigeration cycle with mechanical subcooling , 1994 .

[24]  Frank P. Incropera,et al.  Fundamentals of Heat and Mass Transfer , 1981 .

[25]  Rita Mastrullo,et al.  Change in energy performance as a result of a R422D retrofit: An experimental analysis for a vapor compression refrigeration plant for a walk-in cooler , 2011 .

[26]  Syed M. Zubair,et al.  Second-law-based thermodynamic analysis of two-stage and mechanical-subcooling refrigeration cycles , 1996 .

[27]  Syed M. Zubair.  Improvement of refrigeration/air-conditioning performance with mechanical sub-cooling , 1990 .