scholarly journals CASCADE REFRIGERATION SYSTEM FOR LOW TEMPERATURES USING NATURAL FLUIDS

2021 ◽  
Vol 20 (2) ◽  
pp. 20
Author(s):  
V. B. Rangel ◽  
A. G. S. Almeida
Keyword(s):  
Low Temperatures ◽  
Refrigeration Cycle ◽  
Refrigeration System ◽  
Cascade System ◽  
Energy And Exergy ◽  
Laws Of Thermodynamics ◽  
Cascade Refrigeration System ◽  
Cascade Refrigeration ◽  
Natural Refrigerant ◽  
Exergy Analyses

Cascade refrigeration systems work with two or more serial disposed cycles and can obtain internal temperatures below -60°C, which is necessary for several activities in medicine and scientific research. This paper presents a thermodynamic analysis of cascade system refrigeration using natural refrigerant fluids for ultra-low temperatures. These fluids are environmentally friendly refrigerant and are an alternative to hydro chlorofluorocarbons (HCFCs) and to hydrofluorocarbons (HFCs). Energy and exergy analyses were performed using a thermodynamic model based on the law of conservation of mass and also on the first and second laws of thermodynamics. A simulator was developed to assess the technical practicability of this system, considering it running as a real refrigeration cycle. Natural fluids have best performance energetically and environmentally.

scholarly journals OPTIMIZATION OF CASCADE REFRIGERATION SYSTEM TO ACHIEVE LOWER TEMPERATURES

2020 ◽  
Vol 5 (8) ◽  
Author(s):  
Andrew Raphael Santos Conceição Mendonça ◽  
Francisco Souza Almeida ◽  
Luiz Gustavo Da Cruz Duarte ◽  
Antonio Gabriel Souza Almeida
Keyword(s):  
Thermal Efficiency ◽  
Low Temperatures ◽  
Refrigeration System ◽  
Cascade System ◽  
Theoretical Predictions ◽  
Cascade Refrigeration System ◽  
Mechanical Components ◽  
Cascade Refrigeration ◽  
The Impact ◽  
Made In

Achieve ultra-low temperatures is usually possible due to the use of cascade configurations refrigeration systems. Commonly, the observed results do not match the expected theoretical predictions. Therefore, in order to increase thermal efficiency and reach lower temperatures, adjustments and modifications in mechanical components of refrigeration system, in refrigerant fluids charges, and in general parts arrangement can be done. The system presented herein features a cascade configuration that uses R-404a and R-508b, and was previously able to reach -70°C. This study investigates the impact of optimization changes made in this existing cascade system, regarding the use of a more powerful compressor, in order to achieve -86°C inside the freezer. A series of tests was conducted for each one of the changes, and  this paper presents the complete methodology used, as well as the results found. As we will be able to notice, the results did not match the expected temperature, but contributed to the evolution of the experiment.

Energy and Exergy Analysis of Cascade Refrigeration System Using MC22 and MC134 on HTC, R404A and R502 on LTC

2021 ◽  
Vol 80 (1) ◽  
pp. 73-83
Author(s):  
Hendri ◽  
Roswati Nurhasanah ◽  
Prayudi ◽  
Suhengki
Keyword(s):  
Low Temperature ◽  
Exergy Analysis ◽  
Refrigeration System ◽  
Low Temperature Storage ◽  
Energy And Exergy ◽  
Energy And Exergy Analysis ◽  
Cascade Refrigeration System ◽  
Cascade Refrigeration ◽  
Better Than ◽  
Temperature Storage

Low temperature storage with a single refrigeration system only stable up to 228 K temperature. The purpose of this study is to develop a low temperature cool storage with cascade refrigeration system, with hydrocarbon refrigerants in terms of energy and exergy analysis. Experimental research in laboratories using refrigerant hydrocarbon MC22 and MC134 on the hight temperature circuit, and R404A and R502 using on low temperature circuit. Condenser heat exchanger using a type of exchanger plate. Resulting from this research, obtained that result the MC22/R404A, MC22/R502 and MC134/R404A refrigerant pair can reach a temperature of 220 K. The MC22/R404A refrigerant pair has god performance, COP, total loss exergy, and exergy efficiency is better than MC22/R502, and MC134/R04A refrigerant pairs.

Energetic, Exergetic, Environmental, and Economic Assessment of a Cascade Refrigeration System Operating with Four Different Ecological Refrigerant Pairs

2021 ◽  
pp. 2150025
Author(s):  
Cleison Henrique de Paula ◽  
Willian Moreira Duarte ◽  
Thiago Torres Martins Rocha ◽  
Raphael Nunes de Oliveira ◽  
Antônio Augusto Torres Maia
Keyword(s):  
Coefficient Of Performance ◽  
Maintenance Cost ◽  
Temperature Cycle ◽  
Refrigeration System ◽  
Cascade System ◽  
Cost Rate ◽  
Total Plant ◽  
Cascade Refrigeration System ◽  
Cascade Refrigeration ◽  
System Operating

In this work, a cascade refrigeration system operating with four different ecological refrigerant pairs was modeled. This system uses R744 (Carbon dioxide) in the low-temperature cycle and operates with R290 (propane), R1234yf (2,3,3,3-tetrafluoropropene), R152a (1,1-difluorethane), and R717 (ammonia) in the high-temperature cycle. Energetic, exergetic, environmental, and economic performance of the cascade system was investigated to determine the most appropriate ecological refrigerant couple. The parameters used in each mentioned performance were COP (Coefficient of Performance), [Formula: see text] (Exergy Efficiency), TEWI (Total Equivalent Warming Impact), ECOP (Ecological coefficient of performance), and [Formula: see text] (Total plant cost rate), respectively. The results showed that the cascade refrigeration system operating with R744/R717 provided the best performance for the thermodynamic conditions analyzed, presenting a COP of 2.10, [Formula: see text] of 56.9%, [Formula: see text] of 24 334 USD/year, ECOP of 4.86, and TEWI of 25.67 tons of CO2. Finally, evaluating the total plant cost rate of this cascade system, it was noted that the capital and maintenance cost rate [Formula: see text] corresponds to 89.1% of the [Formula: see text] value, the operational cost rate [Formula: see text] corresponds to 10.27% of the [Formula: see text] value and the environmental cost rate [Formula: see text] corresponds to 0.63% of [Formula: see text].

Energy and exergy analysis of low GWP refrigerants in cascade refrigeration system

Energy ◽  
2019 ◽  
Vol 170 ◽  
pp. 1170-1180 ◽  
Author(s):  
Zhili Sun ◽  
Qifan Wang ◽  
Zhiyuan Xie ◽  
Shengchun Liu ◽  
Dandan Su ◽  
...  
Keyword(s):  
Exergy Analysis ◽  
Refrigeration System ◽  
Energy And Exergy ◽  
Energy And Exergy Analysis ◽  
Cascade Refrigeration System ◽  
Cascade Refrigeration

Experimental of Cascade Refrigeration System Using Natural Refrigerant Mixture Ethane and Carbon Dioxide at Low Temperature Circuit and Natural Refrigerant Propane at High Temperature Circuit

2013 ◽  
Vol 388 ◽  
pp. 96-100
Author(s):  
Nasruddin ◽  
M. Idrus Alhamid ◽  
Darwin R.B. Syaka ◽  
Arnas
Keyword(s):  
Carbon Dioxide ◽  
Low Temperature ◽  
Cold Storage ◽  
Cooling Load ◽  
Refrigeration System ◽  
Refrigerant Mixture ◽  
Cascade Refrigeration System ◽  
Cascade Refrigeration ◽  
Natural Refrigerant ◽  
Refrigeration Machine

Medicine and biomedical research activities require cold storage to store biomedical specimens such as, for example, stem cell, sperm, blood and other organs. During storage, to prevent the specimen from damage required a special cold storage reaches -80°C [1]. Using single cycle refrigeration machine can only reach -40°C, and performance deteriorates below -35°C drop in pressure associated with evaporation. Thus, to reach lower temperatures, use cascade refrigeration machine [2]. During this low-temperature circuit cascade refrigeration systems still use refrigerants that contain ozone-depleting or global warming (CFCs and HCFCs). To overcome this, a mixture of carbon dioxide and ethane azeotropic a promising alternative refrigerants. Simulation studies and experiments indicate a mixture of carbon dioxide and ethane were able to achieve the minimum temperature to -80°C [4-7]. With the mass ratio 70% R170 and 30% R744 circuit at low temperature refrigeration systems and uses a capillary tube expansion device 0.054 inch diameter with a length of 6 meters and 3 meters then use an electric heater as the cooling load. Cooling load is given by the variation of 90 W, 120 W and 150 W at a cabin in the low temperature circuit. From the experiment will be known characteristics of cascade refrigeration system with refrigerant mixture and will get the parameter data to make cascade refrigeration machine.

APPLICATION OF CASCADE REFRIGERATION SYSTEM WITH MIXING REFRIGERANT IN COLD AIR CUTTING

2005 ◽  
Vol 19 (01n03) ◽  
pp. 521-523
Author(s):  
Y. YANG ◽  
M. W. TONG ◽  
G. YANG ◽  
X. P. WANG
Keyword(s):  
High Efficiency ◽  
Cutting Process ◽  
Refrigeration System ◽  
Cascade System ◽  
Cold Air ◽  
High Efficient ◽  
Cascade Refrigeration System ◽  
Cascade Refrigeration ◽  
Mechanical Cutting ◽  
Optimal Mixing

In the mechanical cutting process, the replacement of traditional cutting solution with cold air can avoid the pollution of environment. In order to high efficient the refrigerating device and flexible adjust the temperature of cold air, it is necessary to use cascade refrigeration system to supply cool quantity for the compressed air. The introduction of a two-component non-azeotropic mixing refrigerant into the cryogenic part of the cascade system, can effectively solve the problems of the system working at too high pressure and the volume expanding of refrigerant in case of the cascade refrigeration sets closed down. However, the filling ratio of mixing refrigerants impact on the relationships among the closing down pressure, refrigerating output and refrigerating efficiency. On the basis of computing and experiment, the optimal mixing ratio of refrigerant R22/R13 and a low temperature of -60° were obtained in this study. A cold air injecting device possessing high efficiency in energy saving has also been designed and manufactured. The cold air, generated from this cascade system and employed in a cutting process, takes good comprehensive effects on machining and cutting.

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