ABSTRACT
As an efficient and energy conservation technology, heat pumps working with R22, which are scheduled to be phased out by Montreal Protocol, are widely used in China at present. The global deteriorating ecology environment would accelerate the phase-out time of R22 in developing countries. Therefore, as a matter of urgency, an eco-friendly substitute should be investigated in order to replace R22. Under this context, and with a consideration of the environmental protection, R744/R161 mixture refrigerant is proposed. R744/R161 mixture refrigerant’s condensation pressure is reduced and its flammability and explosivity are suppressed. A thermodynamic model is developed, and under the given working conditions, the performances of subcritical heat pump system using R744/R161 mixture of variable mass fraction are discussed and compared with those of the R22 system. The optimal mass fraction of R744/R161 is given, which corresponds to a maximal heating coefficient of performance. The simulation results show that R744/R161 mixture can work as a competitive alternative to R22 in heat pump system.
KEYWORDS
PAPER SUBMITTED: 2013-10-13
PAPER REVISED: 2014-03-18
PAPER ACCEPTED: 2014-07-13
PUBLISHED ONLINE: 2015-01-04
THERMAL SCIENCE YEAR
2014, VOLUME
18, ISSUE
Issue 5, PAGES [1673 - 1677]
- Blarke, M. B., Lund H., Large-Scale Heat Pumps in Sustainable Energy, Systems System and Project Perspectives, Thermal Science, 11 (2007), 3, pp. 143-152
- Yang, Z., Wu, X., Retrofits and Options for the Alternatives to HCFC-22, Energy, 59 (2013), Sept., pp. 1-21
- Calm, J. M., Hourahan, G. C., Refrigerant Data Update, Heating/Piping/Air Conditioning Engineering, 79 (2007), 1, pp. 50-64
- Kim, M. H., et al., Fundamental Process and System Design Issues in CO2 Vapor Compression Systems, Progress in Energy and Combustion Science, 30 (2004), 2, pp. 119-174
- Sarkar, J., et al., Experimental Investigation of Transcritical CO2 Heat Pump for Simultaneous Water Cooling and Heating, Thermal Science, 14 (2010), 1, pp. 57-64
- Wang, Q., et al., Experimental Studies on a Mixture of HFC-32/125/161 as an Alternative Refrigerant to HCFC-22 in the Presence of Polyol Ester, Fluid Phase Equilibria, 293 (2010), 1, pp. 110-116
- Xuan, Y. M., Chen, G. M., Experimental Study on HFC-161 Mixture as an Alternative Refrigerant to R502, International Journal of Refrigeration, 28 (2005), 3, pp. 436-441
- Han, X. H., et al., Cycle Performances of the Mixture HFC-161 + HFC-134a as the Substitution of HFC- 134a in Automotive Air Conditioning Systems, International Journal of Refrigeration, 36 (2013), 3, pp. 913-920
- Xie, P. Z., Guo, Z. K., Experimental Research on Combustion Inhibition of R161 (in Chinese), Refrigeration and Air-Conditioning, 13 (2013), 3, pp. 51-56, 40
- Nicola, G. D., et al., Blends of Carbon Dioxide and HFCs as Working Fluids for the Low-Temperature Circuit in Cascade Refrigerating System, International Journal of Refrigeration, 28 (2005), 2, pp. 130-140
- Zhang, X. P., et al., Theoretical and Experimental Studies on Optimum Heat Rejection Pressure for a CO2 Heat Pump System, Applied Thermal Engineering, 30 (2010), 16, pp. 2537-2544
- Klein, S. A., Engineering Equation Solver, Academic Commercial Version 9.433, #2313, 2012
- Lemmon, E. W., et al., Reference Fluid Thermodynamic and Transport Properties (REFPROP), NIST Standard Reference Database 23, Version 9.0, 2013
- General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China, Standardization Administration of the People's Republic of China (in Chinese), Heat Pump Water Heater for Household and Similar Application, GB/T23137-2008