Refrigerated Railroad Car Design for Shipping Frozen Meat Using Alternative Refrigerants

2014 ◽  
Author(s):  
Beyza Alkan ◽  
Ali Celen ◽  
Alican Çebi ◽  
Ahmet Selim Dalkilic ◽  
Somchai Wongwises
Keyword(s):  
Coefficient Of Performance ◽  
Rolling Stock ◽  
Condensation Temperature ◽  
Refrigeration System ◽  
Alternative Refrigerants ◽  
Potential Growth ◽  
Cold Room ◽  
Insulation Thickness ◽  
Perishable Freight ◽  
Railroad Cars

Refrigerated railroad cars, known as reefers, are railroad rolling stock designed to carry perishable freight at specific temperatures. They are insulated boxcars that keep the cargo at a regulated temperature. As soon as railroad cars had the capability to keep a load cold, the potential growth of the meat, dairy, fruit and brewery industries became nearly unlimited. In this paper, a cold-room system in a railroad car was investigated as a case study to illustrate the use of the sample model. The change of substitute refrigerants and insulation thickness of the cold rooms’ refrigeration system was also considered in the model. The coefficient of performance (COP), refrigerant flow rate and capacities of each component of the refrigeration system were calculated for the refrigerants R12, R22, R134a, R290, R410A, R430A, R431A, R436A, R507A, R600a as part of this analysis. As a result of the energy analyses, all of the substitute refrigerants have a slightly lower COP and require higher compressor work than R12 and R22 for a condensation temperature of 40°C. The frozen meats have an evaporation temperature of −25°C related to the preserved product in the case studies. Influences of the insulation thickness of the wall on evaporator capacity and outside temperature of various cities on the condenser are also studied.

Fundamental Basis and Application of Cold-Room Project Design: A Case Study of Frigoship

2013 ◽  
Author(s):  
Merve Öztürk ◽  
Emine Göktepe ◽  
Ali Celen ◽  
Alican Çebi ◽  
Ahmet Selim Dalkılıç ◽  
...  
Keyword(s):  
Sea Water ◽  
Condensation Temperature ◽  
Refrigeration System ◽  
Alternative Refrigerants ◽  
Cold Room ◽  
Hfc 134A ◽  
Proposed Model ◽  
Insulation Thickness ◽  
Compressor Work

In this paper, a cold-room system in a frigoship was analyzed as a case study to demonstrate the application of the proposed model. The model was also evaluated in terms of the alteration of alternative refrigerants and insulation thickness of the cold rooms’ refrigeration system. The coefficients of performance (COP), refrigerant charge rates, and capacities of each component of the refrigeration system for the refrigerants CFC-12, HCFC-22 and their alternatives, such as HFC-134a, HFC-410a, HFC-404a, HFC-407c, and HFC-507 were determined by considering the effects of the main parameters of the performance analysis, such as refrigerant type, Based on the results of the energy analyses, all of the alternative refrigerants have a slightly lower COP and require higher compressor work than CFC-12 and HCFC-22 for condensation temperature of 40°C. The hunted fishes have an evaporation temperature of −25°C regarding with the preserved product in the case studies. Effects of isolation thickness of wall on evaporator capacity and sea water temperature on condenser are also investigated. Also variation capacity of system components such as evaporator, condenser and compressor with relative humidity of neighbor volume is studied.

scholarly journals COP enhancement of vapour compression refrigeration system using dedicated mechanical subcooling cycle

2020 ◽  
Vol 39 (3) ◽  
pp. 776-784
Author(s):  
T.S. Mogaji ◽  
A. Awolala ◽  
O.Z. Ayodeji ◽  
P.B. Mogaji ◽  
D.E. Philip
Keyword(s):  
System Performance ◽  
Cooling Capacity ◽  
Coefficient Of Performance ◽  
Condensation Temperature ◽  
Refrigeration System ◽  
Wide Range ◽  
Cascade Refrigeration System ◽  
Cascade Refrigeration ◽  
Vapour Compression ◽  
Better Than

This study focused on development of an improved vapour compression refrigeration system (IVCR system). Dedicated mechanical subcooling cycle is employed in attaining the developed IVCR system. The system is composed of two cycles cascade refrigeration system working with R134a. It consists of a rectangular shape with total storage space of 0.582 m3, made of galvanized mild steel and internally insulated with 0.05 m polystyrene foam. Tests under a wide range operating temperature conditions were carried out on the developed IVCR system. Performance evaluation of the system was characterized in terms of cooling capacity and coefficient of performance (COP). Experimental results showed that the COP of the subcooled system improved better than that of the main system from 18.0% to about 33.5% over an evaporating temperature range of -10 to 30oC. It can be concluded that the use of dedicated sub cooling cycle in VCR system is more efficient and suitable for the betterment of thermal system performance. Keywords: Vapour compression Refrigeration system, Coefficient of performance, dedicated subcooled system, Condensation temperature, Evaporation temperature.

Effect of Hydrofluorocarbons and Hydrofluoroolefins in a Household Refrigerator as a Substitute for R134a

2019 ◽  
Vol 969 ◽  
pp. 199-204
Author(s):  
Shaik Mohammad Hasheer ◽  
Kolla Srinivas
Keyword(s):  
Cooling Capacity ◽  
Operating Conditions ◽  
Coefficient Of Performance ◽  
Condensation Temperature ◽  
Outlet Temperature ◽  
Refrigeration System ◽  
Volumetric Cooling ◽  
Work Done ◽  
Theoretical Results ◽  
Hfc 152A

Now a days R134a can be used in domestic refrigerators and in air conditioning of automobiles. As per Kyoto protocol the usage of R134a is restricted due to their higher GWP value. The GWP value of this refrigerant is around 1430. So in this article, thermodynamic analysis of HFC-152a, HFO refrigerants-1234ze(E) and 1234yf was done in a household refrigeration system as direct substitute to HFC-134a.The performance of the household refrigerator was compared in terms of outlet temperature of the compressor, volumetric cooling capacity (VCC), refrigeration effect, work done by the compressor and coefficient of performance (COP). The entire analysis is carried out at various operating conditions of condenser and evaporator temperatures i.e. condensation temperature of 25°C,35°C & 45°C and evaporating temperatures ranging between −20°C to 10°C.From the theoretical results, it can be concluded that R1234yf can be used as a direct substitute to R134a.

scholarly journals Exergetic performance analysis of low GWP alternative refrigerants for R404A in a refrigeration system

2021 ◽  
Author(s):  
Mehmet Altinkaynak
Keyword(s):  
Cooling System ◽  
Operating Conditions ◽  
Coefficient Of Performance ◽  
Working Fluid ◽  
Refrigeration System ◽  
Alternative Refrigerants ◽  
Condenser Temperature ◽  
Parametric Analyses ◽  
Low Global Warming Potential ◽  
Very High

Abstract According to the regulation of European Union laws in 2014, it was inevitable to switch to low global warming potential (GWP) fluids in the refrigeration systems where the R404A working fluid is currently used. The GWP of R404A is very high, and the potential for ozone depletion is zero. In this study, energetic and exergetic performance assessment of a theoretical refrigeration system was carried out for R404 refrigerant and its alternatives, comparatively. The analyses were made for R448A, R449A, R452A and R404A. The results of the analysis were presented separately in the tables and graphs. According to the results, the cooling system working with R448A exhibited the best performance with a coefficient of performance (COP) value of 2.467 within the alternatives of R404A followed by R449A and R452A, where the COP values were calculated as 2.419 and 2.313, respectively. In addition, the exergy efficiencies of the system were calculated as 20.62%, 20.22% and 19.33% for R448A, R449A and R452A, respectively. For the base calculations made for R404A, the COP of the system was estimated as 2.477, where the exergy efficiency was 20.71%. Under the same operating conditions, the total exergy destruction rates for R404A, R448A, R449A and R452A working fluids were found to be 3.201 kW, 3.217 kW, 3.298 kW and 3.488 kW, respectively. Furthermore, parametric analyses were carried out in order to investigate the effects of different system parameters such as evaporator and condenser temperature.

scholarly journals Performance characteristics of low global warming potential R134a alternative refrigerants in ejector-expansion refrigeration system

2016 ◽  
Vol 37 (4) ◽  
pp. 55-72
Author(s):  
Shubham Mishra ◽  
Jahar Sarkar
Keyword(s):  
Cooling Capacity ◽  
Area Ratio ◽  
Coefficient Of Performance ◽  
Air Conditioner ◽  
Refrigeration System ◽  
Alternative Refrigerants ◽  
Entrainment Ratio ◽  
Maximum Improvement ◽  
Maximum Coefficient ◽  
Volumetric Cooling

AbstractPerformance assessment of ejector-expansion vapor compression refrigeration system with eco-friendly R134a alternative refrigerants (R152a, R1234yf, R600a, R600, R290, R161, R32, and propylene) is presented for air-conditioning application. Ejector has been modeled by considering experimental data based correlations of component efficiencies to take care of all irreversibilities. Ejector area ratio has been optimized based on maximum coefficient of performance (COP) for typical air-conditioner operating temperatures. Selected refrigerants have been compared based on area ratio, pressure lift ratio, entrainment ratio, COP, COP improvement and volumetric cooling capacity. Effects of normal boiling point and critical point on the performances have been studied as well. Using ejector as an expansion device, maximum improvement in COP is noted in R1234yf (10.1%), which reduces the COP deviation with R134a (4.5% less in basic cycle and 2.5% less in ejector cycle). Hence, R1234yf seems to be best alternative for ejector expansion system due to its mild flammability and comparable volumetric capacity and cooling COP. refrigerant R161 is superior to R134a in terms of both COP and volumetric cooling capacity, although may be restricted for low capacity application due to its flammability.

scholarly journals Performance evaluation of an adsorption refrigeration system powered by solar heat storage based on Moroccan irradiation

2020 ◽  
Vol 307 ◽  
pp. 01014
Author(s):  
Hicham BOUSHABA ◽  
Abdelaziz MIMET ◽  
Mohammed El GANAOUI ◽  
Abderrahman MOURADI
Keyword(s):  
Heat Storage ◽  
Operating Conditions ◽  
Coefficient Of Performance ◽  
Solar Irradiation ◽  
Cooling Power ◽  
Condensation Temperature ◽  
Refrigeration System ◽  
Adsorption Refrigeration ◽  
The Real ◽  
Solar Heat

The aim of this paperwork is to provide a performance comparative study of an adsorption refrigeration system powered by solar heat storage based on Moroccan irradiation. The system operates with ammonia as refrigerant and activated carbon as adsorbent. A parabolic through collector is used to collect the solar energy and store it in a heat storage tank. A dynamic simulation program interpreting the real behavior of the system has been developed. The pressure, temperature and adsorbed mass profiles in the Adsorber have been revealed. The system performance is estimated in terms of the specific cooling power (SCP) and the solar coefficient of performance (SCOP). The solar irradiation and the real ambient temperature variations corresponding to the six climatic zones in Morocco are considered. The effect of those conditions on the performance of the system has been investigated. The results show the capability of our system to realize more than one cycle and produce cold during the day. For an optimal configuration of the system and operating conditions of evaporation temperature, Tev=0 °C, condensation temperature, Tcon=30 °C and generation temperature, T3=100 °C, the process could achieve a SCP of 151 W.kg-1and its solar COP could attain 0.148. The system performances improve especially in sunny area.

scholarly journals Energy and Thermal Conductivity Assessment of Dimethyl-Ether and its Azeotropic Mixtures as Alternative Low Global Warming Potential Refrigerants in a Refrigeration System

2021 ◽  
Vol 25 (1) ◽  
pp. 12-28
Author(s):  
Bukola Olalekan Bolaji ◽  
Olatunde Ajani Oyelaran ◽  
Israel Olutunji Abiala ◽  
Tunde Oluwatoyin Ogundana ◽  
Semiu Taiwo Amosun
Keyword(s):  
Thermal Conductivity ◽  
Global Warming ◽  
Dimethyl Ether ◽  
Pressure Ratio ◽  
Cooling Capacity ◽  
Coefficient Of Performance ◽  
Refrigeration System ◽  
Environmental Benefit ◽  
Alternative Refrigerants ◽  
Azeotropic Mixtures

Abstract Substituting Hydrofluorocarbons with natural refrigerants in domestic refrigerators will significantly reduce the direct contributions of fluorinated gases to global warming which will be of great environmental benefit. In this study, the performances of dimethyl-ether (RE170) and its azeotropic mixtures (R510A and R511A) in a refrigeration system were assessed theoretically and compare with that of conventional refrigerant. The study revealed that the three investigated alternative refrigerants exhibited significantly good heat transfer characteristics, low pressure ratio, high latent heat in the liquid phase which resulted in their high thermal conductivity and Volumetric Cooling Capacity (VCC). The thermal conductivity of the refrigerants reduces while the evaporating temperature rises and the value obtained for RE170 was the highest among the four refrigerants studied. The Coefficient of Performance (COP) for RE170, R510A and R511A were higher than that of R134a by 6.20, 10.06 and 3.02 % respectively while their power consumptions per ton of refrigeration were lower than that of R134a by 6.99, 11.04 and 1.47 % respectively. In conclusion, dimethyl-ether and its azeotropic mixtures performed better than R134a in that they have higher thermal conductivity, refrigerating effect, VCC, COP, lower power consumption per ton of refrigeration and hence, they can be considered as suitable replacements for R134a in domestic refrigerator.

scholarly journals Case study of liquid suction heat exchanger in a mechanical refrigeration system using alternative refrigerants

2020 ◽  
Vol 9 (3) ◽  
pp. 644
Author(s):  
Raid Ahmed Mahmood
Keyword(s):  
Heat Exchanger ◽  
System Performance ◽  
Good Alternative ◽  
High Response ◽  
Coefficient Of Performance ◽  
Alternative Refrigerant ◽  
Refrigeration System ◽  
Alternative Refrigerants

This paper investigates the effect of adding a liquid-suction heat exchanger on the performance of a mechanical refrigeration system using alternative refrigerants. Engineering Equation Solver (EES) was used to simulate a mechanical refrigeration system in two configurations: modified system with liquid-suction heat exchanger and system without liquid-suction heat exchanger. The results revealed that the liquid-suction heat exchanger has a significant effect on the system performance as it influences the subcooling and superheating temperatures. The results also showed that the highest value of the coefficient of performance (COP) was achieved by the modified system with refrigerant type R134a, COP was about 7% and 12% higher than that of refrigerants R600a and R22 respectively. It also presented that R600a has high response to increase the refrigerant effect when the liquid-suction heat exchanger is used. R600a is good alternative refrigerant and it can be used in the mechanical refrigeration system, but its COP is lower than that of R134a.  

scholarly journals Performance Evaluation of an Adsorption Heat Pump System Using MSC-30/R1234yf Pair with the Impact of Thermal Masses

2021 ◽  
Vol 11 (5) ◽  
pp. 2279
Author(s):  
Sangwon Seo ◽  
František Mikšík ◽  
Yuta Maeshiro ◽  
Kyaw Thu ◽  
Takahiko Miyazaki
Keyword(s):  
Heat Pump ◽  
Adsorption Isotherms ◽  
Coefficient Of Performance ◽  
Variable Pressure ◽  
Condensation Temperature ◽  
Relative Pressure ◽  
Pump System ◽  
Adsorption Heat Pump ◽  
Adsorbed Phase ◽  
The Impact

In this study, we evaluated the performance of low Global Warming Potential (GWP) refrigerant R1234yf on the activated carbon (MSC-30) for adsorption heating applications. The adsorption isotherms of MSC-30/R1234yf were measured using a constant-volume–variable-pressure (CVVP) method from very low relative pressure to the practical operating ranges. The data were fitted with several isotherm models using non-linear curve fitting. An improved equilibrium model was employed to investigate the influence of dead thermal masses, i.e., the heat exchanger assembly and the non-adsorbing part of the adsorbent. The model employed the model for the isosteric heat of adsorption where the adsorbed phase volume was accounted for. The performance of the heat pump was compared with MSC-30/R134a pair using the data from the literature. The analysis covered the desorption temperature ranging from 60 °C to 90 °C, with the evaporation temperature at 5 °C and the adsorption temperature and condensation temperature set to 30 °C. It was observed that the adsorption isotherms of R1234yf on MSC-30 were relatively lower than those of R134a by approximately 12%. The coefficient of performance (COP) of the selected pair was found to vary from 0.03 to 0.35 depending on the heat source temperature. We demonstrated that due to lower latent heat, MSC-30/R1234yf pair exhibits slightly lower cycle performance compared to the MSC-30/R134a pair. However, the widespread adaptation of environmentally friendly R1234yf in automobile heat pump systems may call for the implementation of adsorption systems such as the direct hybridization using a single refrigerant. The isotherm and performance data presented in this work will be essential for such applications.

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