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Jagdev Singh - One of the best experts on this subject based on the ideXlab platform.
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ann approach for irreversibility analysis of Vapor Compression Refrigeration system using r134a lpg blend as replacement of r134a
Journal of Thermal Analysis and Calorimetry, 2019Co-Authors: Jatinder Gill, Jagdev Singh, Olayinka S Ohunakin, D S AdelekanAbstract:This paper experimentally evaluated the irreversibility in the components (compressor, condenser, capillary tube, and eVaporator) of the Vapor Compression Refrigeration system (VCRS) using R134a/LPG refrigerant as a replacement for R134a. For this aim, different tests were conducted for various eVaporator and condenser temperatures under controlled surrounding conditions. The results reported that the irreversibilities in the components of VCRS using R134a/LPG blend were found lesser than irreversibilities in the components of VCRS using R134a under similar experimental conditions. Artificial neural network (ANN) models were developed to predict the second law of efficiency and total irreversibility of the Refrigeration system. ANN and ANFIS model predictions were also compared with experimental results and an absolute fraction of variance in range of 0.980–0.994 and 0.951–0.977, root-mean-square error in the range of 0.1636–0.2387 and 0.2501–0.4542 and mean absolute percentage error in the range of 0.159–0.572 and 0.308–0.931%, respectively, were estimated. The outcomes suggested that ANN model shows better statistical prediction than ANFIS model.
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Component-wise exergy and energy analysis of Vapor Compression Refrigeration system using mixture of R134a and LPG as refrigerant
Heat and Mass Transfer, 2018Co-Authors: Jatinder Gill, Jagdev SinghAbstract:In this work, the experimental examination was carried out using a mixture of R134a and LPG refrigerant (consisting of R134a and LPG in a proportion of 28:72 by weight) as a replacement for R134a in a Vapor Compression Refrigeration system. Exergy and energy tests were carried out at different eVaporator and condenser temperatures with controlled environmental conditions. The results showed that the exergy destruction in the compressor, condenser, eVaporator, and a capillary tube of the R134a / LPG Refrigeration system was found lower by approximately 11.13–3.41%, 2.24–3.43%, 12.02–13.47% and 1.54–5.61% respectively. The compressor exhibits the highest level of destruction, accompanied by a condenser, an eVaporator and a capillary tube in Refrigeration systems. The Refrigeration capacity, COP and power consumption of the compressor of the R134a /LPG Refrigeration system were detected higher and lower compared to the R134a Refrigeration system by about 7.04–11.41%, 15.1–17.82%, and 3.83–8.08% respectively. Also, the miscibility of R134a and LPG blend with mineral oil discovered good. The R134a and LPG refrigerant mixture proposed in this study perform superior to R134a from component-wise exergy and energy analyses under similar experimental conditions.
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use of artificial neural network approach for depicting mass flow rate of r134a lpg refrigerant through straight and helical coiled adiabatic capillary tubes of Vapor Compression Refrigeration system
International Journal of Refrigeration-revue Internationale Du Froid, 2018Co-Authors: Jatinder Gill, Jagdev SinghAbstract:Abstract In this work, an experimental investigation carried out with R134a and LPG refrigerant mixture for depicting mass flow rate through straight and helical coil adiabatic capillary tubes in a Vapor Compression Refrigeration system.Various experiments conducted under steady-state conditions, by changing capillary tube length, inner diameter, coil diameter and degree of subcooling. The outcomes demonstrated that mass flow rate through helical coil capillary tube discovered lower than straight capillary tube by about 5−16%. Dimensionless correlation and Artificial Neural Network (ANN) models developed to predict the mass flow rate. It found that dimensionless correlation and ANN model predictions concurred well with experimental results and brought out an absolute fraction of variance of 0.961 and 0.988, root mean square error of 0.489 kg/h and 0.275 kg/h and mean absolute percentage error of 4.75% and 2.31%, respectively. The outcomes suggested that ANN model shows better statistical prediction than dimensionless correlation model.
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energy analysis of Vapor Compression Refrigeration system using mixture of r134a and lpg as refrigerant
International Journal of Refrigeration-revue Internationale Du Froid, 2017Co-Authors: Jatinder Gill, Jagdev SinghAbstract:Abstract According to Kyoto protocol, R134a must be phased out soon due to its high global warming potential of 1430. In this work, an experimental investigation is carried out with R134a and LPG refrigerant mixture (composed of R134a and LPG in the ratio of 28:72 by weight) as an alternative to R134a in a Vapor Compression Refrigeration system. Performance tests were performed under different eVaporator and condenser temperatures with controlled ambient conditions. The results showed that the R134a and LPG refrigerant mixture has a higher coefficient of performance and lower compressor discharge temperature and pull down time as compared to R134a by about 15.1–17.82%, 2.10–13.86% and 1.01–5.90% respectively. Furthermore, the miscibility of R134a/LPG with mineral oil as a lubricant was also found good. In conclusion, the mixing refrigerant R134a/LPG proposed in this study seems to be an appropriate long-term candidate to replace R134a as a new generation refrigerant of VCRS, because of its well environmentally acceptable properties and its favorable Refrigeration performances.
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energetic and exergetic performance analysis of the Vapor Compression Refrigeration system using adaptive neuro fuzzy inference system approach
Experimental Thermal and Fluid Science, 2017Co-Authors: Jatinder Gill, Jagdev SinghAbstract:Abstract According to Kyoto protocol R134a must be phased out soon due to its high global warming potential of 1430. In this work, an experimental investigation has made with R134a and LPG refrigerant mixture (composed of R134a and LPG in the ratio of 28:72 by weight) as an alternative to R134a in a Vapor Compression Refrigeration system. Performance tests performed under different eVaporator and condenser temperatures with controlled ambient conditions. The results showed that the R134a and LPG refrigerant mixture has higher values of coefficient of performance and exergy efficiency as compared to R134a by about 10.57–15.28% and 6.60–11.40%, respectively. The applicability of adaptive neuro-fuzzy inference system (ANFIS) to predict COP, Total Exergy destruction and Exergy efficiency of R134a/LPG system also investigated. For this aim, some of the experimental data utilized for training, an ANFIS model for the system developed. The ANFIS predictions agreed well with the experimental results with an absolute fraction of variance (R 2 ) in the range of 0.994–0.998, a root mean square error (RMSE) in the range of 0.0018–0.1907 and mean absolute percentage error (MAPE) in the range of 0.103–0.897%. The results suggest that the ANFIS approach can be used successfully for predicting the performance of Vapor Compression Refrigeration systems.
Jatinder Gill - One of the best experts on this subject based on the ideXlab platform.
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ann approach for irreversibility analysis of Vapor Compression Refrigeration system using r134a lpg blend as replacement of r134a
Journal of Thermal Analysis and Calorimetry, 2019Co-Authors: Jatinder Gill, Jagdev Singh, Olayinka S Ohunakin, D S AdelekanAbstract:This paper experimentally evaluated the irreversibility in the components (compressor, condenser, capillary tube, and eVaporator) of the Vapor Compression Refrigeration system (VCRS) using R134a/LPG refrigerant as a replacement for R134a. For this aim, different tests were conducted for various eVaporator and condenser temperatures under controlled surrounding conditions. The results reported that the irreversibilities in the components of VCRS using R134a/LPG blend were found lesser than irreversibilities in the components of VCRS using R134a under similar experimental conditions. Artificial neural network (ANN) models were developed to predict the second law of efficiency and total irreversibility of the Refrigeration system. ANN and ANFIS model predictions were also compared with experimental results and an absolute fraction of variance in range of 0.980–0.994 and 0.951–0.977, root-mean-square error in the range of 0.1636–0.2387 and 0.2501–0.4542 and mean absolute percentage error in the range of 0.159–0.572 and 0.308–0.931%, respectively, were estimated. The outcomes suggested that ANN model shows better statistical prediction than ANFIS model.
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Component-wise exergy and energy analysis of Vapor Compression Refrigeration system using mixture of R134a and LPG as refrigerant
Heat and Mass Transfer, 2018Co-Authors: Jatinder Gill, Jagdev SinghAbstract:In this work, the experimental examination was carried out using a mixture of R134a and LPG refrigerant (consisting of R134a and LPG in a proportion of 28:72 by weight) as a replacement for R134a in a Vapor Compression Refrigeration system. Exergy and energy tests were carried out at different eVaporator and condenser temperatures with controlled environmental conditions. The results showed that the exergy destruction in the compressor, condenser, eVaporator, and a capillary tube of the R134a / LPG Refrigeration system was found lower by approximately 11.13–3.41%, 2.24–3.43%, 12.02–13.47% and 1.54–5.61% respectively. The compressor exhibits the highest level of destruction, accompanied by a condenser, an eVaporator and a capillary tube in Refrigeration systems. The Refrigeration capacity, COP and power consumption of the compressor of the R134a /LPG Refrigeration system were detected higher and lower compared to the R134a Refrigeration system by about 7.04–11.41%, 15.1–17.82%, and 3.83–8.08% respectively. Also, the miscibility of R134a and LPG blend with mineral oil discovered good. The R134a and LPG refrigerant mixture proposed in this study perform superior to R134a from component-wise exergy and energy analyses under similar experimental conditions.
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use of artificial neural network approach for depicting mass flow rate of r134a lpg refrigerant through straight and helical coiled adiabatic capillary tubes of Vapor Compression Refrigeration system
International Journal of Refrigeration-revue Internationale Du Froid, 2018Co-Authors: Jatinder Gill, Jagdev SinghAbstract:Abstract In this work, an experimental investigation carried out with R134a and LPG refrigerant mixture for depicting mass flow rate through straight and helical coil adiabatic capillary tubes in a Vapor Compression Refrigeration system.Various experiments conducted under steady-state conditions, by changing capillary tube length, inner diameter, coil diameter and degree of subcooling. The outcomes demonstrated that mass flow rate through helical coil capillary tube discovered lower than straight capillary tube by about 5−16%. Dimensionless correlation and Artificial Neural Network (ANN) models developed to predict the mass flow rate. It found that dimensionless correlation and ANN model predictions concurred well with experimental results and brought out an absolute fraction of variance of 0.961 and 0.988, root mean square error of 0.489 kg/h and 0.275 kg/h and mean absolute percentage error of 4.75% and 2.31%, respectively. The outcomes suggested that ANN model shows better statistical prediction than dimensionless correlation model.
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energy analysis of Vapor Compression Refrigeration system using mixture of r134a and lpg as refrigerant
International Journal of Refrigeration-revue Internationale Du Froid, 2017Co-Authors: Jatinder Gill, Jagdev SinghAbstract:Abstract According to Kyoto protocol, R134a must be phased out soon due to its high global warming potential of 1430. In this work, an experimental investigation is carried out with R134a and LPG refrigerant mixture (composed of R134a and LPG in the ratio of 28:72 by weight) as an alternative to R134a in a Vapor Compression Refrigeration system. Performance tests were performed under different eVaporator and condenser temperatures with controlled ambient conditions. The results showed that the R134a and LPG refrigerant mixture has a higher coefficient of performance and lower compressor discharge temperature and pull down time as compared to R134a by about 15.1–17.82%, 2.10–13.86% and 1.01–5.90% respectively. Furthermore, the miscibility of R134a/LPG with mineral oil as a lubricant was also found good. In conclusion, the mixing refrigerant R134a/LPG proposed in this study seems to be an appropriate long-term candidate to replace R134a as a new generation refrigerant of VCRS, because of its well environmentally acceptable properties and its favorable Refrigeration performances.
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energetic and exergetic performance analysis of the Vapor Compression Refrigeration system using adaptive neuro fuzzy inference system approach
Experimental Thermal and Fluid Science, 2017Co-Authors: Jatinder Gill, Jagdev SinghAbstract:Abstract According to Kyoto protocol R134a must be phased out soon due to its high global warming potential of 1430. In this work, an experimental investigation has made with R134a and LPG refrigerant mixture (composed of R134a and LPG in the ratio of 28:72 by weight) as an alternative to R134a in a Vapor Compression Refrigeration system. Performance tests performed under different eVaporator and condenser temperatures with controlled ambient conditions. The results showed that the R134a and LPG refrigerant mixture has higher values of coefficient of performance and exergy efficiency as compared to R134a by about 10.57–15.28% and 6.60–11.40%, respectively. The applicability of adaptive neuro-fuzzy inference system (ANFIS) to predict COP, Total Exergy destruction and Exergy efficiency of R134a/LPG system also investigated. For this aim, some of the experimental data utilized for training, an ANFIS model for the system developed. The ANFIS predictions agreed well with the experimental results with an absolute fraction of variance (R 2 ) in the range of 0.994–0.998, a root mean square error (RMSE) in the range of 0.0018–0.1907 and mean absolute percentage error (MAPE) in the range of 0.103–0.897%. The results suggest that the ANFIS approach can be used successfully for predicting the performance of Vapor Compression Refrigeration systems.
B Saleh - One of the best experts on this subject based on the ideXlab platform.
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energy and exergy analysis of an integrated organic rankine cycle Vapor Compression Refrigeration system
Applied Thermal Engineering, 2018Co-Authors: B SalehAbstract:Abstract In the present study, the performance of an integrated organic Rankine cycle-Vapor Compression Refrigeration (ORC-VCR) system is investigated from the viewpoint of energy and exergy analysis. The system performance was represented by system coefficient of performance (COPS), system exergy efficiency (ηe,sys), turbine pressure ratio (TPR), and total mass flow rate of the working fluid for each kW cooling capacity ( m t o t a l ). Many common and new hydrocarbons, hydrofluorocarbons, fluorocarbons, hydrofluoroethers, and hydrofluoroolefins were suggested as working fluids. The influences of various parameters such as the boiler, condenser, and eVaporator temperatures, along with compressor and turbine isentropic efficiencies, on the system performance were also investigated. The results revealed that the best system performance was attained with the uppermost critical temperature dry working fluid. Among all suggested candidates, R602 is shown to be the most suitable working fluid for the ORC-VCR system from system performance and environmental issues viewpoints. However, due to its flammability, extra precautions should be taken. The highest COPS, ηe,sys, TPR, and the corresponding m t o t a l using R602 are 0.99, 53.8%, 12.2, and 0.005 kg s−1 kW−1, respectively at a condenser temperature of 25 °C and the typical values for the rest parameters.
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parametric and working fluid analysis of a combined organic rankine Vapor Compression Refrigeration system activated by low grade thermal energy
Journal of Advanced Research, 2016Co-Authors: B SalehAbstract:Abstract The potential use of many common hydrofluorocarbons and hydrocarbons as well as new hydrofluoroolefins, i.e. R1234yf and R1234ze(E) working fluids for a combined organic Rankine cycle and Vapor Compression Refrigeration (ORC-VCR) system activated by low-grade thermal energy is evaluated. The basic ORC operates between 80 and 40 °C typical for low-grade thermal energy power plants while the basic VCR cycle operates between 5 and 40 °C. The system performance is characterized by the overall system coefficient of performance (COPS) and the total mass flow rate of the working fluid for each kW cooling capacity ( m total ). The effects of different working parameters such as the eVaporator, condenser, and boiler temperatures on the system performance are examined. The results illustrate that the maximum COPS values are attained using the highest boiling candidates with overhanging T-s diagram, i.e. R245fa and R600, while R600 has the lowest m total under the considered operating conditions. Among the proposed candidates, R600 is the best candidate for the ORC-VCR system from the perspectives of environmental issues and system performance. Nevertheless, its flammability should attract enough attention. The maximum COPS using R600 is found to reach up to 0.718 at a condenser temperature of 30 °C and the basic values for the remaining parameters.
Somchai Wongwises - One of the best experts on this subject based on the ideXlab platform.
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application of the heat pipe to enhance the performance of the Vapor Compression Refrigeration system
Case Studies in Thermal Engineering, 2019Co-Authors: Santiphap Nakkaew, Somchai Wongwises, Thunyawat Chitipalungsri, Ho Seon Ahn, Dongwook Jerng, Lazarus Godson Asirvatham, Ahmet Selim Dalkilic, Omid MahianAbstract:Abstract This paper presents an application of the heat pipe to enhance the performance of the air conditioner. The study is done in two steps. First, the effect of pertinent parameters on the heat transfer rate of the heat pipe set is investigated. Then the heat pipe set is installed in the split-type air conditioner and tested in the actual condition. The heat pipe set consists of a heat pipe, holder, and plate fins. The length of the heat pipe is 300 mm. The working fluid inside the heat pipe is deionized water. Two different geometries of holder which are A-geometry and B-geometry are used in the study. Both holders are made of copper. The numbers of heat pipe in each set are 2, 4 and 6. The experimental results show that the maximum heat transfer rate obtained from the heat pipe set is about 240 W at the air velocity of 5 m/s and the heater surface temperature of 70 ๐C. The heat pipe set with A-geometry consisting of 6 heat pipes is the best configuration. However, this configuration provides the highest air-side pressure drop because of the highest velocity. The best heat pipe set is installed at the outlet of the compressor in the air conditioner with a cooling capacity of 9,000 BTU/hr. The experimental results show that the energy efficiency ratios (EER) of the air conditioners with heat pipe set are slightly higher than those of the conventional air conditioner. The EER of air conditioners with copper holder of heat pipe increases about 3.11%. The results from the present study are important for enhancing the performance of the Vapor Compression Refrigeration system.
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miniature Vapor Compression Refrigeration system for electronics cooling
Case Studies in Thermal Engineering, 2019Co-Authors: Akasi Poachaiyapoom, Jirawa Mounkong, Somchai Wongwises, Rattapon LeardkunAbstract:Abstract A miniature Vapor Compression Refrigeration system using R134a is investigated for electronics cooling. The system consists of four main components: an eVaporator, a compressor, a capillary tube, and a condenser. The eVaporator is a micro-channel heat sink with 106 rectangular cross-sectional channels. Each micro-channel has a depth of 450 µm, a width of 150 µm, a wall thickness of 150 µm, and a length of 20 mm. Experimental conditions include compressor speeds ranging between 3000 and 6000 RPM and heating power of 100 W, 150 W, and 200 W. The experimental results show that increased compressor speed could reduce the surface temperature of the heater but also decrease the coefficient of performance (COP). The highest COP gained is 9.069 at a compressor speed of 3000 RPM and a heating power of 200 W, which yields the heater surface temperature of 73.3 °C. This miniature Vapor Compression Refrigeration system could be used for electronics cooling with the most suitable conditions at heating power of 200 W and compressor speed of 3000 RPM. The proposed system is not suitable for electronics cooling at a heating power of 100 W and 150 W, because the heater surface temperature is less than 40 °C.
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Miniature Vapor Compression Refrigeration system for electronics cooling
Elsevier, 2019Co-Authors: Akasi Poachaiyapoom, Rattapo Leardku, Jirawa Mounkong, Somchai WongwisesAbstract:A miniature Vapor Compression Refrigeration system using R134a is investigated for electronics cooling. The system consists of four main components: an eVaporator, a compressor, a capillary tube, and a condenser. The eVaporator is a micro-channel heat sink with 106 rectangular cross-sectional channels. Each micro-channel has a depth of 450 µm, a width of 150 µm, a wall thickness of 150 µm, and a length of 20 mm. Experimental conditions include compressor speeds ranging between 3000 and 6000 RPM and heating power of 100 W, 150 W, and 200 W. The experimental results show that increased compressor speed could reduce the surface temperature of the heater but also decrease the coefficient of performance (COP). The highest COP gained is 9.069 at a compressor speed of 3000 RPM and a heating power of 200 W, which yields the heater surface temperature of 73.3 °C. This miniature Vapor Compression Refrigeration system could be used for electronics cooling with the most suitable conditions at heating power of 200 W and compressor speed of 3000 RPM. The proposed system is not suitable for electronics cooling at a heating power of 100 W and 150 W, because the heater surface temperature is less than 40 °C. Keywords: Micro-channel, Vapor Compression system, Heat sink, Electronics coolin
Xiaosong Zhang - One of the best experts on this subject based on the ideXlab platform.
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energy efficient and economic technologies for air conditioning with Vapor Compression Refrigeration a comprehensive review
Applied Energy, 2018Co-Authors: Xiaohui She, Xiaosong Zhang, Yi Chen, Lin Cong, Binjian Nie, Guanghui Leng, Hao Peng, Tao Wen, Hongxing Yang, Yimo LuoAbstract:Abstract Vapor Compression Refrigeration Systems (VCRS) are widely used to provide cooling or freezing for domestic/office buildings, supermarkets, data centres, etc., which expend 15% of globally electricity and contribute to ∼10% of greenhouse gas emissions globally. It is reported that cooling demand is expected to grow tenfold by 2050. Therefore, it is critical to improve the efficiency of the VCRS. In this paper, a comprehensive review of advanced and hot technologies is conducted for the VCRS. These technologies include radiative cooling, cold energy storage, defrosting and frost-free, temperature and humidity independent control (THIC), ground source heat pump (GSHP), refrigerant subcooling, and condensing heat recovery. Radiative cooling could produce a cold source ∼8 °C lower than the surroundings, which reduces the electricity consumption of the VCRS by ∼21%; cold energy storage is used to shift the peak cooling load, and as a result, the electricity consumption and operation cost of the VCRS could be reduced by ∼12% and ∼32%, respectively; frosting is a big issue of the VCRS especially for freezing applications, and more than 60% of electricity consumption for defrosting could be saved with the advanced defrosting and frost-free technologies; THIC deals with the building sensible load and latent load separately, which not only increases the COP of the VCRS by ∼35%, but also improves the building thermal comfort; GSHP uses the ground as a low-temperature cooling source for condensing the refrigerant in the VCRS in summer, which decreases the condensing temperature by ∼5 °C and correspondingly increases the COP of the VCRS by ∼14%; refrigerant subcooling and condensing heat recovery can increase the refrigerating capacity and achieve multi-functions of the VCRS, respectively. The review is summarized in terms of the technology classification, basic ideas, advantages/disadvantages, current research status and efforts to be made in the future.
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a proposed subcooling method for Vapor Compression Refrigeration cycle based on expansion power recovery
International Journal of Refrigeration-revue Internationale Du Froid, 2014Co-Authors: Xiaosong ZhangAbstract:Abstract This study proposes a new subcooling method for Vapor Compression Refrigeration cycle based on expansion power recovery. In a main Refrigeration cycle, expander output power is employed to drive a compressor of the auxiliary subcooling cycle, and refrigerant at the outlet of condenser is subcooled by the eVaporative cooler, which makes the hybrid system get much higher COP. Various refrigerants, including R12, R134a, R22, R32, R404A, R41, R507A, R717, and R744, are considered. Thermodynamic analysis is made to discuss the effects of operation parameters (expander efficiency and inlet temperature of cooling water) on the system performance. Results show that the proposed hybrid Vapor Compression Refrigeration system achieves much higher COP than the conventional Vapor Compression Refrigeration system, conventional mechanical subcooling system and conventional expansion power recovery system, with maximum COP increments 67.76%, 19.27% and 17.73%, respectively when R744 works as the refrigerant in the main Refrigeration cycle. It is most beneficial for R12 and R717 in the auxiliary subcooling cycle and R744, R404A and R507A in the main Refrigeration cycle.
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thermodynamic analysis of a novel energy efficient Refrigeration system subcooled by liquid desiccant dehumidification and eVaporation
Energy Conversion and Management, 2014Co-Authors: Xiaosong ZhangAbstract:A new energy-efficient Refrigeration system subcooled by liquid desiccant dehumidification and eVaporation was proposed in this paper. In the system, liquid desiccant system could produce very dry air for an indirect eVaporative cooler, which would subcool the Vapor Compression Refrigeration system to get higher COP than conventional Refrigeration system. The desiccant cooling system can use the condensation heat for the desiccant regeneration. Thermodynamic analysis is made to discuss the effects of operation parameters (condensing temperature, liquid desiccant concentration, ambient air temperature and relative humidity) on the system performance. Results show that the proposed hybrid Vapor Compression Refrigeration system achieves significantly higher COP than conventional Vapor Compression Refrigeration system, and even higher than the reverse Carnot cycle at the same operation conditions. The maximum COPs of the hybrid systems using hot air and ambient air are 18.8% and 16.3% higher than that of the conventional Vapor Compression Refrigeration system under varied conditions, respectively.
