SIMULATION OF A LOW TEMPERATURE EVAPORATOR IN A CASCADE REFRIGERATION SYSTEM

2011 ◽  
Vol 19 (03) ◽  
pp. 203-212 ◽  
Author(s):  
DUSHYANTHA GUNAWARDANE ◽  
PRADEEP BANSAL
Keyword(s):  
Low Temperature ◽  
Cross Flow ◽  
Finned Tube ◽  
Temperature Cycle ◽  
Refrigeration System ◽  
Mass Flow Rates ◽  
Cascade Refrigeration System ◽  
Refrigeration Capacity ◽  
Cascade Refrigeration ◽  
System Operating

This paper presents a mathematical model for the evaporator of a cascade refrigeration system, operating down to -40°C. The system uses Carbon dioxide (R744) and Propylene (R1270), respectively, as the low temperature and high temperature cycle refrigerant. The model is developed in Engineering Equation Solver software package following the elemental Number of Transfer Units-effectiveness method, where frost has not been considered. The evaporator is a cross-flow finned tube serpentine heat exchanger, which was divided into numerous elements along the flow path of the refrigerant. The inputs to the model include inlet temperatures and mass flow rates of both the streams along with the heat flux, while the main outputs are the outlet temperatures, refrigeration capacity and HX effectiveness. The model is found to underpredict the refrigeration capacity by about 10% when compared with experimental data.

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].

A novel low-temperature absorption–compression cascade refrigeration system

2015 ◽  
Vol 75 ◽  
pp. 504-512 ◽  
Author(s):  
Yingjie Xu ◽  
FuSheng Chen ◽  
Qin Wang ◽  
Xiaohong Han ◽  
Dahong Li ◽  
...  
Keyword(s):  
Low Temperature ◽  
Refrigeration System ◽  
Cascade Refrigeration System ◽  
Cascade Refrigeration

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.

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.

Sign in / Sign up

Export Citation Format

Share Document