scholarly journals Integration of the Experimental Results of a Parabolic Trough Collector (PTC) Solar Plant to an Absorption Air-Conditioning System

2018 ◽  
Vol 8 (11) ◽  
pp. 2163 ◽  
Author(s):  
Yuridiana Galindo Luna ◽  
Wilfrido Gómez Franco ◽  
Ulises Dehesa Carrasco ◽  
Rosenberg Romero Domínguez ◽  
José Jiménez García
Keyword(s):  
Cooling System ◽  
Operating Conditions ◽  
Experimental Results ◽  
Coefficient Of Performance ◽  
Lithium Nitrate ◽  
Parabolic Trough ◽  
Parabolic Trough Collector ◽  
Absorption Cooling ◽  
Parametric Analyses ◽  
Absorption Cooling System

The present study reports the experimental results of a parabolic trough collector field and an absorption cooling system with a nominal capacity of 5 kW, which operates with the ammonia-lithium nitrate mixture. The parabolic trough collectors’ field consists of 15 collectors that are made of aluminum plate in the reflector surface and cooper in the absorber tube, with a total area of 38.4 m2. The absorption cooling system consists of 5 plate heat exchangers working as the main components. Parametric analyses were carried out to evaluate the performance of both systems under different operating conditions, in independent way. The results showed that the solar collectors’ field can provide up to 6.5 kW of useful heat to the absorption cooling system at temperatures up to 105 °C with thermal efficiencies up to 19.8% and exergy efficiencies up to 14.93, while the cooling system operated at generation temperatures from 85–95 °C and condensation temperatures between 20 and 28 °C, achieving external coefficients of performance up to 0.56, cooling temperatures as low as 6 °C, and exergy efficiencies up to 0.13. The highest value for the solar coefficient of performance reached 0.07.

scholarly journals Modelling and simulation of a solar absorption cooling system for India

2006 ◽  
Vol 17 (3) ◽  
pp. 65-70 ◽  
Author(s):  
V Mittal ◽  
K S Kasana ◽  
N S Thakur
Keyword(s):  
Surface Area ◽  
Cooling System ◽  
Hot Water ◽  
Coefficient Of Performance ◽  
Reference Temperature ◽  
Inlet Temperature ◽  
Solar Absorption ◽  
Absorption Cooling ◽  
Solar Absorption Cooling ◽  
Absorption Cooling System

This paper presents modelling and simulation of a solar absorption cooling system. In this paper, the modelling of a solar-powered, single stage, absorption cooling system, using a flat plate collector and water–lithium bromide solution, is done. A computer program has been developed for the absorption system to simulate various cycle configurations with the help of various weather data for the village Bahal, District Bhiwani, Haryana, India. The effects of hot water inlet temperatures on the coefficient of performance (COP) and the surface area of the absorption cooling component are studied. The hot water inlet temperature is found to affect the surface area of some of the system components. Moreover the effect of the reference temperature which is the minimum allowable hot water inlet temperature on the fraction of total load met by non-purchased energy (FNP) and coefficient of performance (COP) is studied and it is found that high reference temperature increases the system COP and decreases the surface area of system components but lower reference temperature gives better results for FNP than high reference temperatures.

scholarly journals Thermodynamic Analysis of a Half-Effect Absorption Cooling System Powered by a Low-Enthalpy Geothermal Source

2019 ◽  
Vol 9 (6) ◽  
pp. 1220 ◽  
Author(s):  
Javier Alejandro Hernández-Magallanes ◽  
Jonathan Ibarra-Bahena ◽  
Wilfrido Rivera ◽  
Rosenberg J. Romero ◽  
Efraín Gómez-Arias ◽  
...  
Keyword(s):  
Thermodynamic Analysis ◽  
Cooling System ◽  
Real Data ◽  
Exergy Efficiency ◽  
Volcanic Complex ◽  
Lithium Nitrate ◽  
Absorption Cooling ◽  
Geothermal Wells ◽  
Absorption Cooling System ◽  
System Operating

A thermodynamic analysis of a half-effect absorption cooling system powered by a low-enthalpy geothermal source was carried out. This paper presents modeling of the half-effect absorption cooling system operating with an ammonia/lithium nitrate mixture and based on the first and second laws of thermodynamics, using as energy inputs real data from two geothermal wells located at Las Tres Vírgenes volcanic complex, Baja California Sur, México. Plots of coefficients of performance and exergy efficiency against condenser, evaporator, and generator temperatures are presented for the half-effect cooling system. The results showed that the system was able to operate at generation temperatures between 56 and 70 °C, which were supplied by the geothermal wells in order to produce cooling at temperatures as low as −16 °C, achieving coefficients of performance between 0.10 and 0.36, while the exergy efficiency varied from 0.15 to 0.40 depending on the system operating temperatures.

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.

Design and Construction of an Air Cooled Ammonia Absorber

2009 ◽  
Vol 131 (2) ◽  
Author(s):  
Nicolás Velázquez ◽  
Daniel Sauceda ◽  
Margarito Quintero-Núñez ◽  
Roberto Best
Keyword(s):  
Cooling System ◽  
Operating Conditions ◽  
Array Type ◽  
Finned Tubes ◽  
Advantages And Disadvantages ◽  
Operational Design ◽  
Absorption Cooling ◽  
Solar Generator ◽  
Ammonia Absorption ◽  
Absorption Cooling System

This paper presents the design criteria, methodology. and results of the basic and detailed engineering for a descending film ammonia absorber using air cooled finned tubes, which is part of an advanced absorption cooling system (solar generator absorber heat exchange cycle). The design consists in determining all the construction parameters for the air cooled ammonia absorption unit, starting with the operating conditions defined by a thermodynamical simulation of the process considering both physical and operational design restrictions. The chosen option was based on a comparison between the advantages and disadvantages of each possible array, type, and geometry. After performing the operational simulation, thermal and mechanical designs, and the consistency analysis, it was found that an absorption unit using 29 5/8 NPT 14 (BWG) steel carbon ASTM A-179 tubes, with pure SB-234 aluminum fins was the best option. The tubes are arranged in an equilateral triangle fashion, with crossed air flow cooling.

scholarly journals Thermo-Economic Comparisons of Environmentally Friendly Solar Assisted Absorption Air Conditioning Systems

2021 ◽  
Vol 11 (5) ◽  
pp. 2442
Author(s):  
Adil Al-Falahi ◽  
Falah Alobaid ◽  
Bernd Epple
Keyword(s):  
Cooling System ◽  
Operating Conditions ◽  
Coefficient Of Performance ◽  
Refrigeration Cycle ◽  
Absorption Refrigeration ◽  
Parabolic Trough ◽  
Solar Absorption ◽  
Evacuated Tube Collectors ◽  
Solar Absorption Cooling ◽  
Solar Field

Absorption refrigeration cycle is considered a vital option for thermal cooling processes. Designing new systems is needed to meet the increasing communities’ demands of space cooling. This should be given more attention especially with the increasing conventional fossil fuel energy costs and CO2 emission. This work presents the thermo-economic analysis to compare between different solar absorption cooling system configurations. The proposed system combines a solar field, flashing tank and absorption chiller: two types of absorption cycle H2O-LiBr and NH3-H2O have been compared to each other by parabolic trough collectors and evacuated tube collectors under the same operating conditions. A case study of 200 TR total cooling load is also presented. Results reveal that parabolic trough collector combined with H2O-LiBr (PTC/H2O-LiBr) gives lower design aspects and minimum rates of hourly costs (5.2 $/h) followed by ETC/H2O-LiBr configuration (5.6 $/h). H2O-LiBr gives lower thermo-economic product cost (0.14 $/GJ) compared to the NH3-H2O (0.16 $/GJ). The absorption refrigeration cycle coefficient of performance ranged between 0.5 and 0.9.

scholarly journals Thermal Performance Analysis of an Absorption Cooling System Based on Parabolic Trough Solar Collectors

Energies ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 2679 ◽  
Author(s):  
Jiangjiang Wang ◽  
Rujing Yan ◽  
Zhuang Wang ◽  
Xutao Zhang ◽  
Guohua Shi
Keyword(s):  
Correlation Coefficient ◽  
Cooling System ◽  
Utilization Efficiency ◽  
Design Parameters ◽  
Parabolic Trough ◽  
Absorption Chiller ◽  
Solar Cooling ◽  
Absorption Cooling ◽  
Solar Cooling System ◽  
Absorption Cooling System

Solar radiation intensity significantly influences the cooling loads of building, and the two are correlated and accorded to a certain extent. This study proposes a double effect LiBr–H2O absorption cooling system based on the parabolic trough collector (PTC) of solar heat energy. Thermodynamic models including PTC and absorption chiller are constructed, and their accuracy is verified by comparing the simulation results and the experimental data. Subsequently, the impact of variable design parameters on the thermodynamic performance is analyzed and discussed. The analysis of a solar cooling system in a hotel case study is related to its operation in a typical day, the average coefficient of performance of the absorption chiller is approximately 1.195, and the whole solar cooling system achieves 61.98% solar energy utilization efficiency. Furthermore, the performance comparison of a solar cooling system in different types of building indicates that higher matching and a higher correlation coefficient between the transient solar direct normal irradiance and cooling load is helpful in decreasing the heat loss and improving systemic performance. The solar cooling system in the office building exhibits a correlation coefficient of approximately 0.81 and achieves 69.47% systemic thermal efficiency.

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