scholarly journals Performance Analysis of Solar Combined Ejector-Vapor Compression Cycle Using Environmental Friendly Refrigerants

2013 ◽  
Vol 14 (1) ◽  
Author(s):  
A. B. Kasaeian ◽  
S. Daviran
Keyword(s):  
Internal Heat ◽  
Exergy Efficiency ◽  
Operating Conditions ◽  
Working Fluid ◽  
Vapor Compression ◽  
Refrigeration System ◽  
Environmental Friendly ◽  
Vapor Compression Cycle ◽  
Compression Cycle ◽  
Vapor Compression Refrigeration

In this study, a new model of a solar combined ejector-vapor compression refrigeration system has been considered. The system is equipped with an internal heat exchanger to enhance the performance of the cycle. The effects of working fluid and operating conditions on the system performance including COP, entrainment ratio (ω), compression ratio (rp) and exergy efficiency were investigated. Some working fluids suggested are: R114, R141b, R123, R245fa, R600a, R365mfc, R1234ze(e) and R1234ze(z). The results show that R114 and R1234ze(e) yield the highest COP and exergy efficiency followed by R123, R245fa, R365mfc, R141b, R152a and R600a. It is noticed that the COP value of the new solar ejector-vapor compression refrigeration cycle is higher than that of the conventional ejector cycle with R1234ze(e) for all operating conditions. This paper also demonstrates that R1234ze(e) will be a suitable refrigerant in the solar combined ejector-vapor compression refrigeration system, due to its environmental friendly properties and better performance. ABSTRAK: Kajian ini menganalisa model baru sistem penyejukan mampatan gabungan ejektor-wap solar.Sistem ini dilengkapi dengan penukar haba dalaman untuk meningkatkan prestasi kitaran.Kesan bendalir bekerja dan keadaan operasi pada prestasi sistem termasuk COP, nisbah pemerangkapan (ω), nisbah mampatan (rp) dan kecekapan eksergi telah disiasat.Beberapa bendalir bekerja yang dicadangkan adalah: R114, R141b, R123, R245fa, R600a, R365mfc, R1234ze(e) dan R1234ze(z).Hasil kajian menunjukkan R114 dan R1234ze(e) menghasilkan COP dan kecekapan eksergi tertinggi diikuti oleh R123, R245fa, R365mfc, R141b, R152a dan R600a.Didapati nilai COP kitaran penyejukan mampatan bagi ejektor-wap solar baru adalah lebih tinggi daripada kitaran ejektor konvensional dengan R1234ze(e) bagi semua keadaan operasi.Kertas kerja ini juga menunjukkan bahawa R1234ze(e) boleh menjadi penyejuk yang sesuai dalam sistem penyejukan mampatan gabungan ejektor -wap solar, kerana ianya mempunyai prestasi yang lebih baik serta sifatnya yang lebih mesra alam sekitar. KEYWORDS: environmental friendly refrigerants; solar combined ejector-vapor compression cycle; R1234ze(e)

An Experimental Investigation on Vapor Compression Refrigeration System Cascaded with Ejector Refrigeration System

2021 ◽  
pp. 2150028
Author(s):  
Vikas Kumar ◽  
Gulshan Sachdeva ◽  
Sandeep Tiwari ◽  
Parinam Anuradha ◽  
Vaibhav Jain
Keyword(s):  
Experimental Investigation ◽  
Thermal Equilibrium ◽  
Operating Conditions ◽  
Coefficient Of Performance ◽  
Vapor Compression ◽  
Refrigeration System ◽  
Compression System ◽  
Vapor Compression System ◽  
Vapor Compression Refrigeration ◽  
Cascaded System

A conventional vapor compression refrigeration system (VCRS) cascaded with a heat-assisted ejector refrigeration system (ERS) has been experimentally analyzed. Cascading allows the VCRS to operate at lower condenser temperatures and thus achieve a higher coefficient of performance. In this cascaded system, the condenser of the vapor compression system does not dissipate its heat directly to the evaporator of the ERS; instead, water circulates between the condenser of VCRS and the evaporator of ERS to exchange the heat. Seven ejectors of different geometries have been used in the ERS; however, all the ejectors could not maintain thermal equilibrium at the desired operating conditions. The compressor of the cascaded VCRS consumed 1.3 times less power than the noncascaded VCRS. Furthermore, the cascaded system provided a maximum 87.74% improvement in COP over the noncascaded system for the same operating conditions. The performance of the system remained constant until the critical condenser pressure of the ERS.

scholarly journals Parametric analysis of a combined ejector-vapor compression refrigeration cycle

2020 ◽  
Vol 15 (3) ◽  
pp. 398-408
Author(s):  
I Ouelhazi ◽  
Y Ezzaalouni ◽  
L Kairouani
Keyword(s):  
Current Model ◽  
Operating Conditions ◽  
Coefficient Of Performance ◽  
Refrigeration Cycle ◽  
Vapor Compression ◽  
Refrigeration System ◽  
Entrainment Ratio ◽  
Constant Area ◽  
Vapor Compression Refrigeration Cycle ◽  
Vapor Compression Refrigeration

Abstract From the last few years, the use of efficient ejector in refrigeration systems has been paid a lot of attention. In this article a description of a refrigeration system that combines a basic vapor compression refrigeration cycle with an ejector cooling cycle is presented. A one-dimensional mathematical model is developed using the flow governing thermodynamic equations based on a constant area ejector flow model. The model includes effects of friction at the constant-area mixing chamber. The current model is based on the NIST-REFPROP database for refrigerant property calculations. The model has basically been used to determine the effect of the ejector geometry and operating conditions on the performance of the whole refrigeration system. The results show that the proposed model predicts ejector performance, entrainment ratio and the coefficient of performance of the system and their sensitivity to evaporating and generating temperature of the cascade refrigeration cycle. The simulated performance has been then compared with the available experimental data from the literature for validation.

Thermodynamic Analysis and Working Fluid Optimization of a Combined ORC-VCC System Using Waste Heat From a Marine Diesel Engine

2014 ◽  
Author(s):  
Oumayma Bounefour ◽  
Ahmed Ouadha
Keyword(s):  
Thermodynamic Analysis ◽  
Waste Heat ◽  
Operating Conditions ◽  
Working Fluid ◽  
Vapor Compression ◽  
Marine Diesel ◽  
Vapor Compression Refrigeration ◽  
Propylene Yield ◽  
Fluid Optimization ◽  
Propane Butane

This paper examines through a thermodynamic analysis the feasibility of using waste heat from marine Diesel engines to drive a vapor compression refrigeration system. Several working fluids including propane, butane, isobutane and propylene are considered. Results showed that isobutane and Butane yield the highest performance, whereas propane and propylene yield negligible improvement compared to R134a for operating conditions considered.

scholarly journals An experimental investigation of the saturated vapor pressure of solutions proL pane in compressor oils in the presence of fullerene C60 in oil

2021 ◽  
pp. 89-99
Author(s):  
V. Zhelezny ◽  
S. Korniievych ◽  
O. Khliyeva ◽  
D. Ivchenko
Keyword(s):  
Vapor Pressure ◽  
Saturated Vapor Pressure ◽  
Saturated Vapor ◽  
Fullerene C60 ◽  
Working Fluid ◽  
Vapor Compression ◽  
Refrigeration System ◽  
Concentration Dependences ◽  
Vapor Compression Refrigeration ◽  
Object Of Study

An investigation of the saturated vapor pressure for the solutions of propane in the two type of industrial compressor oils ProEco®RF22S and RENISO SP46, also as in oil ProEco®RF22S containing fullerene C60 6.837·10-4kg·kg-1is presented in this paper. The measurement of the saturated vapor pressure was conducted using a static method in a temperature range (273…333) K and thepropanemass fraction (0.11…0.595) kg·kg-1. An analysis revealed that the expanded uncertainties of the measured saturated vapor pressure do not exceed 0.0419·105Pafor solutionpropane/ProEco®RF22S,0.0716·105Pa for solution propane /RENISO SP46, and 0.0095·105Pa for solution propane/ProEco®RF22 Scontaining C60.The temperature and concentration dependences of the saturated vapor pressure for the object of study have been discussed. The excess of saturated vapor pressure for the solution of propane in oil ProEco®RF22S over the pressure of the solution of propane in oil RENISO SP46 reaches 1.5 105 Pa at a temperature of 330 K and propane fractionof 0.1 kg·kg-1. This effect decreases with temperature decreasing and propane fraction increasing.It was proven that the additive of the fullerene C60 increase the saturated vapor pressure of the solution propane/ProEco® RF22S up to 0.4·105Pa at low temperature and low propane mass fraction insolution. The results obtained proved the expediency of the introduction in the industry the solution of propane/compressor oil ProEco® RF22Scontaining the fullerene C60 as working fluid of vapor compression refrigeration system. The ability of C60additive in oil to increase the saturated vapor pressure of considered working fluid will contribute to increasing the energy efficiency of refrigeration systems.

Experimental Investigation of Vapor Compression Refrigeration System Performance Using Nano-Refrigerant

2014 ◽  
Vol 2 (2) ◽  
pp. 12-27
Author(s):  
Ahmed J. Hamad
Keyword(s):  
Experimental Investigation ◽  
System Performance ◽  
Cuo Nanoparticles ◽  
Working Fluid ◽  
Vapor Compression ◽  
Refrigeration System ◽  
Test Rig ◽  
Vapor Compression Refrigeration ◽  
R 134A ◽  
Thermo Physical Properties

     Experimental investigation of vapor compression refrigeration system performance using Nano-refrigerant is presented in this work. Nano-refrigerant was prepared in current work by mixing 50 nanometers diameter of copper oxide CuO nanoparticles with Polyolester lubrication oil and added to the compressor of the refrigeration system to be mixed with pure refrigerant R-134a during its circulation through refrigeration system. Three concentrations (0.1%, 0.25%, and 0.4%) of CuO-R134 a Nano-refrigerant are used to study the performance of the refrigeration system test rig and to investigate the effect of using Nano-refrigerant as a working fluid compared with pure refrigerant R-134a. The results showed that, the increasing in concentration of CuO nanoparticles in the Nano-refrigerant will significantly enhance the performance of the refrigeration system, as adding nanoparticles will increase the thermal conductivity, heat transfer and improve the thermo-physical properties of Nano-refrigerant. Investigation of performance parameters for refrigeration system using Nano-refrigerant with 0.4% concentration compared with that for pure refrigerant R-134a shows that, Nano-refrigerant has reflect higher performance in range of 10% and 1.5% increase in COP and refrigeration effect respectively and 7% reduction in power consumption for refrigeration system. It can be concluded that, Nano-refrigerants can be efficiently and economically feasible to be used in the vapor compression refrigeration systems.

Performance investigation of organic Rankine-vapor compression refrigeration integrated system activated by renewable energy

2019 ◽  
Vol 20 (2) ◽  
pp. 206 ◽  
Author(s):  
B. Saleh ◽  
Ayman A. Aly ◽  
Ageel F. Alogla ◽  
Awad M. Aljuaid ◽  
Mosleh M. Alharthi ◽  
...  
Keyword(s):  
Renewable Energy ◽  
System Performance ◽  
Organic Rankine Cycle ◽  
Integrated System ◽  
Operating Conditions ◽  
Coefficient Of Performance ◽  
Working Fluid ◽  
Vapor Compression ◽  
Working Fluids ◽  
Vapor Compression Refrigeration

In this article, the performance and working fluid selection for an organic Rankine cycle-vapor compression refrigeration (ORC–VCR) integrated system activated by renewable energy is investigated. The performance of the system is described by the system coefficient of performance (COPS), and the refrigerant mass flow rate per kilowatt refrigeration capacity (m˙total). Twenty-three pure substances are proposed as working fluids for the integrated system. The basic integrated system performance is assessed and compared using the proposed working fluids. The basic VCR cycle works between 35 and 0 °C, while the basic ORC works between 35 and 100 °C. The impacts of different operating parameters such as the evaporator, the boiler, and the condenser temperatures on the ORC–VCR system performance are also examined. The results show that the cyclopentane accomplished the highest system performance under all investigated operating conditions. Accordingly, among the examined 23 working fluids, cyclopentane is the most appropriate working fluid for the integrated system from the viewpoints of environmental concerns and system performance. Nevertheless, due to its high flammability, further restrictions should be taken. The basic integrated system COPS, refrigeration effect, and the corresponding m˙total utilizing cyclopentane are 0.654, 361.3 kW, and 0.596 × 10−2 kg/(s kW), respectively.

scholarly journals Virtual Pressure Sensor for Electronic Expansion Valve Control in a Vapor Compression Refrigeration System

Energies ◽  
2020 ◽  
Vol 13 (18) ◽  
pp. 4917 ◽  
Author(s):  
Jian Sun ◽  
Jin Dong ◽  
Bo Shen ◽  
Wenhua Li
Keyword(s):  
Pressure Sensor ◽  
Operating Conditions ◽  
Sensor Technology ◽  
Vapor Compression ◽  
Control Performance ◽  
Sensor Failure ◽  
Refrigeration System ◽  
Virtual Sensor ◽  
Expansion Valve ◽  
Vapor Compression Refrigeration

Virtual sensor technology, which uses simulation models/algorithms to calculate a value to represent an unmeasured variable or replace a directly measured reading, has attracted many studies in the heating, ventilation, air conditioning and refrigeration (HVAC&R) industry. However, most virtual sensor technologies are developed for fault detection and diagnostics (FDD) purposes, which generally compare the virtual sensor values with actual measured values to detect if any fault occurred and identify the causes that led to the fault. It is rare to see studies focus on control performance of virtual sensors after substituting an actual sensor. This is particularly important for the system with no redundant sensor since a virtual sensor is the most effective way to operate the system in the desirable region when any sensor failure occurs. To address this gap, this paper develops a new virtual pressure sensor technology to substitute the actual pressure measurement for electronic expansion valve (EXV) control in a vapor compression refrigeration system by integrating compressor and valve characteristics. The control performance of this proposed virtual pressure sensor technology under various operating conditions is validated with experimental data. Closed loop EXV control simulations with the proposed virtual pressure sensor are conducted, and the results are analyzed.

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