Operation Conditions Analysis on Solar Energy Compression-Injection Secondary Refrigeration System

2012 ◽  
Vol 178-181 ◽  
pp. 139-143
Author(s):  
Fei Fei Zhang ◽  
Qi Tian ◽  
Li Yuan Yin
Keyword(s):  
Solar Energy ◽  
Injection System ◽  
Condensation Temperature ◽  
Economic Factors ◽  
Refrigeration System ◽  
Cooling Temperature ◽  
Evaporation Temperature ◽  
Operation Conditions ◽  
Heat Collector ◽  
Intermediate Cooling

The COP of compression-injection secondary refrigeration system is increased by 20%-50% than traditional compression-injection system. This paper analyzes the operation conditions on generation temperature, intermediate cooling temperature, condensation temperature and evaporation temperature in the compression-injection secondary refrigerating system powered by solar energy. Comprehensively considering technical and economic factors, the results show that generation temperature should be increased and condensation temperature should be decreased. In addition, the area of solar heat collector and the COP of the system should be considered when we chose the intermediate cooling temperature.

scholarly journals Exergetic and Economic Evaluation of a Transcritical Heat-Driven Compression Refrigeration System with CO2 as the Working Fluid under Hot Climatic Conditions

Entropy ◽  
2019 ◽  
Vol 21 (12) ◽  
pp. 1164 ◽  
Author(s):  
Jing Luo ◽  
Tatiana Morosuk ◽  
George Tsatsaronis ◽  
Bourhan Tashtoush
Keyword(s):  
Ambient Temperature ◽  
Climatic Conditions ◽  
Working Fluid ◽  
Refrigeration System ◽  
Exergetic Efficiency ◽  
Evaporation Temperature ◽  
Aspen Hysys ◽  
Operation Conditions ◽  
Heating Capacity ◽  
Refrigeration Machine

The purpose of this research is to evaluate a transcritical heat-driven compression refrigeration machine with CO2 as the working fluid from thermodynamic and economic viewpoints. Particular attention was paid to air-conditioning applications under hot climatic conditions. The system was simulated by Aspen HYSYS® (AspenTech, Bedford, MA, USA) and optimized by automation based on a genetic algorithm for achieving the highest exergetic efficiency. In the case of producing only refrigeration, the scenario with the ambient temperature of 35 °C and the evaporation temperature of 5 °C showed the best performance with 4.7% exergetic efficiency, while the exergetic efficiency can be improved to 22% by operating the system at the ambient temperature of 45 °C and the evaporation temperature of 5 °C if the available heating capacity within the gas cooler is utilized (cogeneration operation conditions). Besides, an economic analysis based on the total revenue requirement method was given in detail.

scholarly journals Cooling Capacity Test for MIL-101(Cr)/CaCl2 for Adsorption Refrigeration System

Molecules ◽  
2020 ◽  
Vol 25 (17) ◽  
pp. 3975
Author(s):  
Zhongbao Liu ◽  
Banghua Zhao ◽  
Yong Huang ◽  
Xin Qi ◽  
Fengfei Lou
Keyword(s):  
Water Vapor ◽  
Cooling Capacity ◽  
Water Vapor Adsorption ◽  
Condensation Temperature ◽  
Refrigeration System ◽  
Adsorption Refrigeration ◽  
Vapor Adsorption ◽  
Evaporation Temperature ◽  
Adsorption Temperature ◽  
Adsorption Desorption

An MIL-101(Cr) powder material was successfully prepared using the hydrothermal synthesis method, and then the original MIL-101(Cr) was combined with different mass fractions of CaCl2 using the immersion method to obtain a MIL-101(Cr)/CaCl2 composite material. The physical properties of the adsorbent were determined by X-ray powder diffraction (XRD), an N2 adsorption desorption isotherm test, and thermogravimetric analysis (TG). The water vapor adsorption performance of the metal-organic frameworks MOFs was tested with a gravimetric water vapor adsorption instrument to analyze its water vapor adsorption mechanism. Based on the SIMULINK platform in the MATLAB software, a simulation model of the coefficient of performance (COP) and cooling capacity of the adsorption refrigeration system was established, and the variation trends of the COP and cooling capacity of the adsorption refrigeration system under different evaporation/condensation/adsorption/desorption temperatures was theoretically studied. MIL101-(Cr)/CaCl2-20% was selected as the adsorption material in the adsorption refrigeration system through the physical characterization of composite materials with different CaCl2 concentrations by means of adsorption water vapor test experiments. A closed adsorption system performance test device was built based on the liquid level method. The cooling power per unit and adsorbent mass (COP and SCP) of the system were tested at different evaporation temperatures (288 K/293 K/298 K); the adsorption temperature was 298 K, the condensation temperature was 308 K, and the desorption temperature was 353 K. The experimental results showed that COP and SCP increased with the increase in the evaporation temperature. When the evaporation temperature was 298 K, the level of COP was 0.172, and the level of SCP was 136.9 W/kg. The COP and SCP of the system were tested at different adsorption temperatures (293 K/298 K/303 K); the evaporation temperature was 288 K, the condensation temperature was 308 K, and the desorption temperature was 353 K. The experimental results showed that the levels of COP and SCP decreased with the increase in the adsorption temperature. When the adsorption temperature was 293 K, the level of COP was 0.18, and the level of SCP was 142.4 W/kg.

Optimization of Operating Parameters of a Solar Ejector Refrigeration System on Exergy Analysis

2012 ◽  
Vol 178-181 ◽  
pp. 37-41
Author(s):  
Li Yuan Yin ◽  
Qi Tian ◽  
Fei Fei Zhang
Keyword(s):  
Solar Radiation ◽  
Exergy Analysis ◽  
Exergy Efficiency ◽  
Operating Conditions ◽  
Operating Parameters ◽  
Condensation Temperature ◽  
Refrigeration Cycle ◽  
Refrigeration System ◽  
Irreversible Loss ◽  
Evaporation Temperature

Exergy analysis is used as a tool to analyze the performance of a refrigeration system. In this paper, it is based on the following conditions: the solar radiation is set as 750 W/m2, the refrigerating capacity is 10 kW, R141b is fixed as the refrigerant in the refrigeration cycle and ambient temperature to be the reference temperature is 31°C. The exergy analysis results of the solar ejector refrigeration system shows that irreversible loss comes from all components and depends on the operating temperatures. The exergy efficiency increases with the condensation temperature’s decrease or the evaporation temperature’s increase. In the specific evaporation temperature and condensation temperature, the optimum generating temperature can be get when the system exergy efficiency is at its maximum. For the operating conditions in this paper, the optimum generating temperature is 95°C.

Design of a Solar Assisted Absorption Refrigeration System

2014 ◽  
Vol 953-954 ◽  
pp. 66-73
Author(s):  
Yan Ling Liu ◽  
Xue Zeng Shi ◽  
Yuan Yu
Keyword(s):  
High Pressure ◽  
Solar Energy ◽  
System Simulation ◽  
Double Effect ◽  
Absorption Refrigeration ◽  
Refrigeration System ◽  
Absorption System ◽  
Pressure Generator ◽  
Simulation Results ◽  
Absorption Refrigeration System

This paper presents the design of a solar/gas driving double effect LiBr-H2O absorption system. In order to use solar energy more efficiently, a new kind of solar/gas driving double effect LiBr-H2O absorption system is designed. In this system, the high-pressure generator is driven by conventional energy, natural gas, and solar energy together with water vapor generated in the high-pressure generator, which supplies energy to the low-pressure generator for a double effect absorption system. Simulation results illustrate that this kind of system is feasible and economical. Economic evaluation of several systems is also given in this paper in order to get a clear knowledge of the energy consumption of the system.

The Comparison of CFD Flow Field between Slope Solar Energy Power Plant and Traditional Solar Chimney Power Generating Equipment

2013 ◽  
Vol 561 ◽  
pp. 614-619 ◽  
Author(s):  
Qing Ling Li ◽  
Xiao Qing Xie ◽  
Jun Chao ◽  
Xuan Xin ◽  
Yan Zhou
Keyword(s):  
Power Plant ◽  
Velocity Field ◽  
Solar Energy ◽  
Numerical Study ◽  
Solar Chimney ◽  
Heat Collector ◽  
Fluent Software ◽  
Generating Equipment ◽  
The Cost ◽  
Power Generating Equipment

A numerical study with FLUENT software has been carried out as to air performance in the slope solar energy power plant. The velocity field, temperature and pressure fields in the solar chimney, and the simulated result were compared with the simulated result of traditional solar chimney power generating equipment. The simulation results show that distribution of the temperature field and the velocity field in slope solar energy power plant and traditional solar chimney power generating equipment. In the case of the same height, the velocity of traditional is slightly larger than the slope style's, but there is little difference. In order to achieve the same power generation effect, the overall height of slope style is more than the traditional style, but the vertical chimney height of traditional style is greater than the slope style. The cost of construction of vertical chimney is expensive, and many problems have been considered, like radix saposhnikoviae and earthquake prevention, the heat collector also need to be cleaned on time. The slope style can take full advantage of land, the height of vertical chimney will be reduced, so the construction of the chimney will be relatively easy. Rainwater can clean the heat collector when it runs down from it. All things considered. The slope solar energy power plant has more development prospects.

scholarly journals Energetic and exergetic analyses of carbon dioxide transcritical refrigeration systems for hot climates

2015 ◽  
Vol 19 (3) ◽  
pp. 905-914 ◽  
Author(s):  
Farivar Fazelpour
Keyword(s):  
Carbon Dioxide ◽  
Heat Pumps ◽  
Climatic Conditions ◽  
Exergy Efficiency ◽  
Refrigeration System ◽  
Long Period ◽  
Operation Conditions ◽  
Scientific Papers ◽  
System Operating

In the last two decades many scientific papers and reports have been published in the field of the application of the carbon dioxide as a refrigerant for refrigeration systems and heat pumps. Special attention has been paid to the transcritical cycle. However, almost no papers discussed such cycles for hot climates, i.e., when the temperature of the environment is higher than 40?? during a long period of time. This paper deals with the energetic and exergetic evaluation of a CO2 refrigeration system operating in a transcritical cycle under hot climatic conditions. The performance and exergy efficiency of the CO2 refrigeration system depend on the operation conditions. The effect of varying these conditions is also investigated as well as the limitations associated with these conditions.

scholarly journals KAJI PERFORMANSI REFRIGERAN R-290, R-32, DAN R-410A SEBAGAI ALTERNATIF PENGGANTI R-22

2021 ◽  
Vol 4 ◽  
pp. 133-139
Author(s):  
Rikhard Ufie ◽  
Cendy S. Tupamahu ◽  
Sefnath J. E. Sarwuna ◽  
Jufraet Frans
Keyword(s):  
Air Conditioning ◽  
Cooling Capacity ◽  
Coefficient Of Performance ◽  
Condensation Temperature ◽  
Vapor Compression ◽  
Know How ◽  
Evaporation Temperature ◽  
Vapor Compression Cycle ◽  
Compression Cycle ◽  
Refrigeration Capacity

Refrigerant R-22 is a substance that destroys the ozone layer, so that in the field of air conditioning it has begun to be replaced, among others with refrigerants R-32 and R-410a, and also R-290. Through this research, we want to know how much Coefficient of Performance (COP) and Refrigeration Capacity (Qe) can be produced for the four types of refrigerants. The study was carried out theoretically for the working conditions of the vapor compression cycle with an evaporation temperature (Tevap) of 0, -5, and -10oC, a further heated refrigerant temperature (ΔTSH) of 5 oC, a condensation temperature (Tkond) of 45 oC and a low-cold refrigerant temperature. (ΔTSC) 10 oC and compression power of 1 PK . The results of the study show that the Coefficient of Performance (COP) in the use of R-22 and R-290 is higher than the use of R-32 and R-410a, which are 4,920 respectively; 4,891; 4.690 and 4.409 when working at an evaporation temperature of 0 oC; 4.260; 4,234; 4.060 and 3.812 when working at an evaporation temperature of -5 oC; and amounted to 3,730; 3,685; 3,550 and 3,324 if working at an evaporation temperature of -10 oC. Based on the size of the COP, if this installation works with a compression power of 1 PK, then the cooling capacity of the R-22 and R-290 is higher than the R-32 and R-410a, which are 3,617 respectively. kW; 3,597 kW; 3,449 kW and 3,243 kW. If working at an evaporation temperature of 0 oC; 3.133 kW; 3.114 kW; 2,986 kW and 2,804 kW if working at an evaporation temperature of -5 oC; and 2,741 kW; 2,710 kW; 2,611 kW and 2,445 kW if working at an evaporation temperature of -10oC.

scholarly journals A Solar-Energy Method for Reducing Coffee-Drying Costs

1969 ◽  
Vol 47 (4) ◽  
pp. 226-235
Author(s):  
Allan L. Phillips
Keyword(s):  
Solar Energy ◽  
Static Pressure ◽  
Electric Heating ◽  
Operating Costs ◽  
Solar Heat ◽  
Processing Facility ◽  
Heat Collector ◽  
Electricity Costs ◽  
Labor Requirements ◽  
Experimental Processing

1. Modern coffee-processing facilities that have been developed recently have provided the features of low equipment costs and reduced labor requirements, but are somewhat expensive to operate when electric power is used entirely to heat the drying air. 2. The use of solar energy as a heat source was considered, since previous research where solar heat was used to dry other crops indicates that solar heat-collectors could also be used successfully for drying coffee. 3. An experimental processing facility which employs a solar heat-collector was built and operated, and it has been demonstrated that worthwhile reductions in operating costs can be achieved through the use of solar energy. 4. It was concluded that other coffee producers could economically use solar heat-collectors to reduce electricity costs. Drying facilities should be designed using the following as guides: A. Provide 10 square feet of drying-bin area for each 100 hundred-weights of coffee produced yearly. B. Install a fan which will deliver 100 c.f.m. per square foot of bin area against a static pressure of 1-inch water gage. C. Construct the solar heat-collector according to the specifications presented in figure 1. D. Install electric heating elements which provide up to 5,000 w. for each 100 hundred-weights processed yearly.

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