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Guangming Chen - One of the best experts on this subject based on the ideXlab platform.

  • cycle performance studies on a new hfc 161 125 143a mixture as an Alternative Refrigerant to r404a
    Journal of Zhejiang University Science, 2012
    Co-Authors: Yingjie Xu, Q Wang, Menyuan Zhao, Guangming Chen
    Abstract:

    In this paper, a new ternary non-azeotropic mixture of HFC-161/125/143a (0.15/0.45/0.40 in mass fraction), as a promising mixed Refrigerant to R404A, is presented. The ozone depletion potential (ODP) of the new Refrigerant is zero and its basic thermodynamic properties are similar to those of R404A, but its global warming potential (GWP) is much smaller than those of R507A and R404A. Meanwhile, theoretical calculations show that, under the working condition I (the average evaporation temperature: −23 °C, the average condensing temperature: 43 °C, the superheat temperature: 28 °C, the subcooling temperature: 5 °C), the volumetric refrigerating effect and specific refrigerating effect of the new mixture are 2.33% and 15.48% higher, respectively, than those of R404A. The coefficient of performance (COP) of the new mixture is 5.19% higher than that of R404A and the pressure ratio of the new mixture is 0.82% lower than that of R404A. Equally, under the working condition II (the average evaporation temperature: −40 °C, the average condensing temperature: 35 °C, the superheating temperature: 30 °C, the subcooling temperature: 5 °C), the volumetric refrigerating effect and specific refrigerating effect of the new mixture are 2.24% and 20.58% higher, respectively, than those of R404A. The COP of the new mixture is 4.60% higher than that of R404A and the pressure ratio of the new mixture is similar to that of R404A. The performances of the new mixture and R404A are compared in a vapor compressor refrigeration apparatus originally designed for R404A under several working conditions (condensing temperatures: 35–45 °C, evaporation temperatures: −40–−20 °C). Experimental results show that the new mixture can obtain a higher COP, by 6.3% to 12.1%, and a lower pressure ratio, by 1.8% to 6.6%, compared to R404A; although the discharge temperature of the new mixture is slightly higher than that of R404A. The advantages of the new mixture will be further verified in the actual system.

  • cycle performance studies on hfc 161 in a small scale refrigeration system as an Alternative Refrigerant to hfc 410a
    Energy and Buildings, 2012
    Co-Authors: Peng Li, Q Wang, Yingjie Xu, Guangming Chen
    Abstract:

    Abstract In this paper, the Refrigerant HFC-161 as an Alternative Refrigerant to HFC-410A is presented in a small scale refrigeration system. Theoretical cycle performances of HFC-410A, HFC-32 and HFC-161 are calculated and analyzed under the rated working condition. The results show that the COP of HFC-161 is 10.0% and 17.8% higher than that of HFC-32 and HFC-410A, respectively, and the discharge temperature of HFC-161 is the lowest among these Refrigerants. Experimental tests were also performed on a vapor-compression refrigeration system with a rotor compressor which was originally designed for HFC-410A to compare the cycle performance of the HFC-410A, HFC-32 and HFC-161 under different working conditions. Experimental results show that the HFC-161 can achieve higher COP by 15–25% than HFC-410A and HFC-32, and the discharging temperature of HFC-161 is much lower than that of HFC-410A and HFC-32. The power consumption and cooling capacity of HFC-161 are the smallest among these Refrigerants. The cooling capacity and COP of HFC-32 is very similar to those of HFC-410A, but discharging temperature and power consumption of HFC-32 are slightly higher those of HFC-410A under most working conditions. These results show that HFC-161 is a promising Alternative Refrigerant to HFC-410A for small-scale refrigeration systems, which supply a very valuable reference for the actual system of HFC-161.

  • cycle performance study on r32 r125 r161 as an Alternative Refrigerant to r407c
    Applied Thermal Engineering, 2007
    Co-Authors: Q Wang, Guangming Chen
    Abstract:

    This paper presents the new ternary non-azeotropic mixture of R32/R125/R161 as an Alternative Refrigerant to R407C. The physical properties of the ternary mixture are similar to those of R407C, and it is environmental friendly, that is, it has zero ozone-depletion potentials (ODP) and lower global warming potentials (GWP) than R407C. Theoretical cycle performances of R32/R125/R161 and R407C are calculated and analyzed firstly. Based on the theoretical study, experimental tests are performed on a vapor-compression refrigeration system with a rotor compressor which was originally designed for R407C (without any modifications to system components for R407C). Experimental results under different working conditions indicate that the pressure ratio and power consumption of the new Refrigerant are lower than those of R407C, and its refrigerating capacity and coefficient of performance (COP) are superior to those of R407C, respectively, and its discharge temperature is slightly higher than that of R407C. Therefore, the new Refrigerant R32/R125/R161 could be considered as a promising Refrigerant to R407C.

  • Cycle performance study on R32/R125/R161 as an Alternative Refrigerant to R407C
    Applied Thermal Engineering, 2007
    Co-Authors: Qingsheng Wang, Guangming Chen
    Abstract:

    This paper presents the new ternary non-azeotropic mixture of R32/R125/R161 as an Alternative Refrigerant to R407C. The physical properties of the ternary mixture are similar to those of R407C, and it is environmental friendly, that is, it has zero ozone-depletion potentials (ODP) and lower global warming potentials (GWP) than R407C. Theoretical cycle performances of R32/R125/R161 and R407C are calculated and analyzed firstly. Based on the theoretical study, experimental tests are performed on a vapor-compression refrigeration system with a rotor compressor which was originally designed for R407C (without any modifications to system components for R407C). Experimental results under different working conditions indicate that the pressure ratio and power consumption of the new Refrigerant are lower than those of R407C, and its refrigerating capacity and coefficient of performance (COP) are superior to those of R407C, respectively, and its discharge temperature is slightly higher than that of R407C. Therefore, the new Refrigerant R32/R125/R161 could be considered as a promising Refrigerant to R407C.

  • vapor liquid equilibrium data for the binary mixture difluoroethane hfc 32 pentafluoroethane hfc 125 of an Alternative Refrigerant
    Journal of Chemical & Engineering Data, 2007
    Co-Authors: Guangming Chen, Q Wang
    Abstract:

    Isothermal vapor−liquid equilibrium data for the binary system difluoroethane (HFC-32) + pentafluoroethane (HFC-125) were measured at temperatures from (265.15 to 303.15) K by the circulating method in this work. The vapor−liquid equilibrium data were correlated by the Peng−Robinson equation of state combined with a linear combination of the Vidal and Michelsen mixing rule and nonrandom two-liquid model. The results reveal that the correlated data are in a good agreement with the experimental values.

Q Wang - One of the best experts on this subject based on the ideXlab platform.

  • cycle performance studies on a new hfc 161 125 143a mixture as an Alternative Refrigerant to r404a
    Journal of Zhejiang University Science, 2012
    Co-Authors: Yingjie Xu, Q Wang, Menyuan Zhao, Guangming Chen
    Abstract:

    In this paper, a new ternary non-azeotropic mixture of HFC-161/125/143a (0.15/0.45/0.40 in mass fraction), as a promising mixed Refrigerant to R404A, is presented. The ozone depletion potential (ODP) of the new Refrigerant is zero and its basic thermodynamic properties are similar to those of R404A, but its global warming potential (GWP) is much smaller than those of R507A and R404A. Meanwhile, theoretical calculations show that, under the working condition I (the average evaporation temperature: −23 °C, the average condensing temperature: 43 °C, the superheat temperature: 28 °C, the subcooling temperature: 5 °C), the volumetric refrigerating effect and specific refrigerating effect of the new mixture are 2.33% and 15.48% higher, respectively, than those of R404A. The coefficient of performance (COP) of the new mixture is 5.19% higher than that of R404A and the pressure ratio of the new mixture is 0.82% lower than that of R404A. Equally, under the working condition II (the average evaporation temperature: −40 °C, the average condensing temperature: 35 °C, the superheating temperature: 30 °C, the subcooling temperature: 5 °C), the volumetric refrigerating effect and specific refrigerating effect of the new mixture are 2.24% and 20.58% higher, respectively, than those of R404A. The COP of the new mixture is 4.60% higher than that of R404A and the pressure ratio of the new mixture is similar to that of R404A. The performances of the new mixture and R404A are compared in a vapor compressor refrigeration apparatus originally designed for R404A under several working conditions (condensing temperatures: 35–45 °C, evaporation temperatures: −40–−20 °C). Experimental results show that the new mixture can obtain a higher COP, by 6.3% to 12.1%, and a lower pressure ratio, by 1.8% to 6.6%, compared to R404A; although the discharge temperature of the new mixture is slightly higher than that of R404A. The advantages of the new mixture will be further verified in the actual system.

  • cycle performance studies on hfc 161 in a small scale refrigeration system as an Alternative Refrigerant to hfc 410a
    Energy and Buildings, 2012
    Co-Authors: Peng Li, Q Wang, Yingjie Xu, Guangming Chen
    Abstract:

    Abstract In this paper, the Refrigerant HFC-161 as an Alternative Refrigerant to HFC-410A is presented in a small scale refrigeration system. Theoretical cycle performances of HFC-410A, HFC-32 and HFC-161 are calculated and analyzed under the rated working condition. The results show that the COP of HFC-161 is 10.0% and 17.8% higher than that of HFC-32 and HFC-410A, respectively, and the discharge temperature of HFC-161 is the lowest among these Refrigerants. Experimental tests were also performed on a vapor-compression refrigeration system with a rotor compressor which was originally designed for HFC-410A to compare the cycle performance of the HFC-410A, HFC-32 and HFC-161 under different working conditions. Experimental results show that the HFC-161 can achieve higher COP by 15–25% than HFC-410A and HFC-32, and the discharging temperature of HFC-161 is much lower than that of HFC-410A and HFC-32. The power consumption and cooling capacity of HFC-161 are the smallest among these Refrigerants. The cooling capacity and COP of HFC-32 is very similar to those of HFC-410A, but discharging temperature and power consumption of HFC-32 are slightly higher those of HFC-410A under most working conditions. These results show that HFC-161 is a promising Alternative Refrigerant to HFC-410A for small-scale refrigeration systems, which supply a very valuable reference for the actual system of HFC-161.

  • cycle performance study on r32 r125 r161 as an Alternative Refrigerant to r407c
    Applied Thermal Engineering, 2007
    Co-Authors: Q Wang, Guangming Chen
    Abstract:

    This paper presents the new ternary non-azeotropic mixture of R32/R125/R161 as an Alternative Refrigerant to R407C. The physical properties of the ternary mixture are similar to those of R407C, and it is environmental friendly, that is, it has zero ozone-depletion potentials (ODP) and lower global warming potentials (GWP) than R407C. Theoretical cycle performances of R32/R125/R161 and R407C are calculated and analyzed firstly. Based on the theoretical study, experimental tests are performed on a vapor-compression refrigeration system with a rotor compressor which was originally designed for R407C (without any modifications to system components for R407C). Experimental results under different working conditions indicate that the pressure ratio and power consumption of the new Refrigerant are lower than those of R407C, and its refrigerating capacity and coefficient of performance (COP) are superior to those of R407C, respectively, and its discharge temperature is slightly higher than that of R407C. Therefore, the new Refrigerant R32/R125/R161 could be considered as a promising Refrigerant to R407C.

  • vapor liquid equilibrium data for the binary mixture difluoroethane hfc 32 pentafluoroethane hfc 125 of an Alternative Refrigerant
    Journal of Chemical & Engineering Data, 2007
    Co-Authors: Guangming Chen, Q Wang
    Abstract:

    Isothermal vapor−liquid equilibrium data for the binary system difluoroethane (HFC-32) + pentafluoroethane (HFC-125) were measured at temperatures from (265.15 to 303.15) K by the circulating method in this work. The vapor−liquid equilibrium data were correlated by the Peng−Robinson equation of state combined with a linear combination of the Vidal and Michelsen mixing rule and nonrandom two-liquid model. The results reveal that the correlated data are in a good agreement with the experimental values.

  • Cycle performance study on R32/R125/R161 as an Alternative Refrigerant to R407C
    Applied Thermal Engineering, 2007
    Co-Authors: X H Han, Z W Zhu, Q Wang, Guangming Chen
    Abstract:

    This paper presents the new ternary non-azeotropic mixture of R32/R125/R161 as an Alternative Refrigerant to R407C. The physical properties of the ternary mixture are similar to those of R407C, and it is environmental friendly, that is, it has zero ozone-depletion potentials (ODP) and lower global warming potentials (GWP) than R407C. Theoretical cycle performances of R32/R125/R161 and R407C are calculated and analyzed firstly. Based on the theoretical study, experimental tests are performed on a vapor-compression refrigeration system with a rotor compressor which was originally designed for R407C (without any modifications to system components for R407C). Experimental results under different working conditions indicate that the pressure ratio and power consumption of the new Refrigerant are lower than those of R407C, and its refrigerating capacity and coefficient of performance (COP) are superior to those of R407C, respectively, and its discharge temperature is slightly higher than that of R407C. Therefore, the new Refrigerant R32/R125/R161 could be considered as a promising Refrigerant to R407C. ?? 2007 Elsevier Ltd. All rights reserved.

Dongsoo Jung - One of the best experts on this subject based on the ideXlab platform.

  • performance of Alternative Refrigerant r430a on domestic water purifiers
    Energy Conversion and Management, 2009
    Co-Authors: Kijung Park, Dongsoo Jung
    Abstract:

    Abstract In this study, performance of R430A is examined numerically and experimentally in an effort to replace HFC134a used in refrigeration system of domestic water purifiers. Even though HFC134a is used predominantly in such a system these days, it needs to be phased out in near future in most of the developed countries due to its high global warming potential. To solve this problem, cycle simulation and experiments are carried out with a new Refrigerant mixture of 76%R152a/24%R600a using actual water purifiers. This mixture is numbered and listed as R430A by ASHRAE recently. Test results show that the system performance is greatly influenced by the amount of charge due to the small internal volume of the refrigeration system in water purifiers. With the optimum amount of charge of 21–22 g, about 50% of HFC134a, the energy consumption of R430A is 13.4% lower than that of HFC134a. The compressor dome and discharge temperatures and condenser center temperature of R430A are very similar to those of HFC134a for the optimum charge. Overall, R430A, a new long term environmentally safe Refrigerant, is a good Alternative for HFC134a in domestic water purifiers requiring no major change in the system.

  • thermodynamic performance of r502 Alternative Refrigerant mixtures for low temperature and transport applications
    Energy Conversion and Management, 2007
    Co-Authors: Kijung Park, Dongsoo Jung
    Abstract:

    Abstract In this study, two pure hydrocarbon Refrigerants, R1270 (propylene) and R290 (propane), and three binary mixtures composed of R1270, R290 and R152a were tested in a refrigerating bench tester with a scroll compressor in an attempt to substitute R502, which is used in most low temperature and transport refrigeration applications. The test bench provided 3–3.5 kW capacity, and water and water/glycol mixture were employed as the secondary heat transfer fluids. All tests were conducted under the same external conditions, resulting in the average saturation temperatures of −28 and 45 °C in the evaporator and condenser, respectively. The test results showed that all Refrigerants tested had 9.6–18.7% higher capacity and 17.1–27.3% higher COP than R502. The compressor discharge temperature of R1270 was similar to that of R502, while those of all the other Refrigerants were 23.7–27.9 °C lower than that of R502. For all Alternative Refrigerants, the charge was reduced up to 60% as compared to R502. There, of course, was no problem with mineral oil, since the mixtures were mainly composed of hydrocarbons. Since some of them are mixtures, one can change their compositions a little to suit various needs in many applications without significant deterioration of the performance. Overall, these Alternative Refrigerants offer better system performance and reliability than R502 and can be used as long term substitutes for R502 due to their excellent environmental properties.

Kijung Park - One of the best experts on this subject based on the ideXlab platform.

  • performance of Alternative Refrigerant r430a on domestic water purifiers
    Energy Conversion and Management, 2009
    Co-Authors: Kijung Park, Dongsoo Jung
    Abstract:

    Abstract In this study, performance of R430A is examined numerically and experimentally in an effort to replace HFC134a used in refrigeration system of domestic water purifiers. Even though HFC134a is used predominantly in such a system these days, it needs to be phased out in near future in most of the developed countries due to its high global warming potential. To solve this problem, cycle simulation and experiments are carried out with a new Refrigerant mixture of 76%R152a/24%R600a using actual water purifiers. This mixture is numbered and listed as R430A by ASHRAE recently. Test results show that the system performance is greatly influenced by the amount of charge due to the small internal volume of the refrigeration system in water purifiers. With the optimum amount of charge of 21–22 g, about 50% of HFC134a, the energy consumption of R430A is 13.4% lower than that of HFC134a. The compressor dome and discharge temperatures and condenser center temperature of R430A are very similar to those of HFC134a for the optimum charge. Overall, R430A, a new long term environmentally safe Refrigerant, is a good Alternative for HFC134a in domestic water purifiers requiring no major change in the system.

  • performance of Alternative Refrigerant r430a on refrigeration system of water purifiers
    2008
    Co-Authors: Kijung Park, Dongsoon Jung, Sanghyon Park
    Abstract:

    In this study, thermodynamic performance of R430A is examined numerically and experimentally in an effort to replace HFC134a used in refrigeration system of domestic water purifiers. Even though HFC134a is used predominantly in such a system these days, it needs to be phased out in near future in Europe and most of the developed countries due to its high global warming potential. To solve this problem, cycle simulation and experiments are carried out with a new Refrigerant mixture of 76%R152a/24%R600a using actual water purifiers. This mixture is numbered and listed as R430A by ASHRAE recently. Test results show that the system performance is greatly influenced by the amount of charge due to the small internal volume of the refrigeration system in water purifiers. With the optimum amount of charge of 21 to 22 grams, about 50% of HFC134a, the energy consumption of R430A is 12% lower than that of HFC134a. The compressor dome and discharge temperatures and condenser center temperature of R430A are very similar to those of HFC134a for the optimum charge. Overall, R430A, a new long term environmentally safe Refrigerant, is a good Alternative for HFC134a in domestic water purifiers requiring no major change in the system.

  • thermodynamic performance of r502 Alternative Refrigerant mixtures for low temperature and transport applications
    Energy Conversion and Management, 2007
    Co-Authors: Kijung Park, Dongsoo Jung
    Abstract:

    Abstract In this study, two pure hydrocarbon Refrigerants, R1270 (propylene) and R290 (propane), and three binary mixtures composed of R1270, R290 and R152a were tested in a refrigerating bench tester with a scroll compressor in an attempt to substitute R502, which is used in most low temperature and transport refrigeration applications. The test bench provided 3–3.5 kW capacity, and water and water/glycol mixture were employed as the secondary heat transfer fluids. All tests were conducted under the same external conditions, resulting in the average saturation temperatures of −28 and 45 °C in the evaporator and condenser, respectively. The test results showed that all Refrigerants tested had 9.6–18.7% higher capacity and 17.1–27.3% higher COP than R502. The compressor discharge temperature of R1270 was similar to that of R502, while those of all the other Refrigerants were 23.7–27.9 °C lower than that of R502. For all Alternative Refrigerants, the charge was reduced up to 60% as compared to R502. There, of course, was no problem with mineral oil, since the mixtures were mainly composed of hydrocarbons. Since some of them are mixtures, one can change their compositions a little to suit various needs in many applications without significant deterioration of the performance. Overall, these Alternative Refrigerants offer better system performance and reliability than R502 and can be used as long term substitutes for R502 due to their excellent environmental properties.

Edward J. Maginn - One of the best experts on this subject based on the ideXlab platform.

  • Molecular Modeling of the Vapor−Liquid Equilibrium Properties of the Alternative Refrigerant 2,3,3,3-Tetrafluoro-1-propene (HFO-1234yf)
    Journal of Physical Chemistry Letters, 2010
    Co-Authors: Gabriele Raabe, Edward J. Maginn
    Abstract:

    The European Union legislation 2006/40/EC results in a phase-out of the presently used tetrafluoroethane Refrigerant R134a from automotive heating ventilation and air conditioning systems. This necessitates the adoption of Alternative Refrigerants, and 2,3,3,3-tetrafluoro-1-propene (HFO-1234yf) is currently regarded as the most promising Alternative Refrigerant. However, the lack of experimental data hampers independent studies on its performance in technical applications. We have developed a force field for HFO-1234yf that enables reliable predictions of its thermophysical properties via molecular simulation. The simulation results complement experimental data and provide a molecular-level perspective of the fluid behavior. In this letter we present the force field and its validation using Gibbs ensemble simulations on its vapor liquid equilibria.

  • molecular modeling of the vapor liquid equilibrium properties of the Alternative Refrigerant 2 3 3 3 tetrafluoro 1 propene hfo 1234yf
    Journal of Physical Chemistry Letters, 2010
    Co-Authors: Gabriele Raabe, Edward J. Maginn
    Abstract:

    The European Union legislation 2006/40/EC results in a phase-out of the presently used tetrafluoroethane Refrigerant R134a from automotive heating ventilation and air conditioning systems. This necessitates the adoption of Alternative Refrigerants, and 2,3,3,3-tetrafluoro-1-propene (HFO-1234yf) is currently regarded as the most promising Alternative Refrigerant. However, the lack of experimental data hampers independent studies on its performance in technical applications. We have developed a force field for HFO-1234yf that enables reliable predictions of its thermophysical properties via molecular simulation. The simulation results complement experimental data and provide a molecular-level perspective of the fluid behavior. In this letter we present the force field and its validation using Gibbs ensemble simulations on its vapor liquid equilibria.