Investigation of an Energy Source Temperature for NH3 + NaSCN and NH3 + LiNO3 Absorption Refrigeration Systems

2020 ◽  
Vol 142 (10) ◽  
Author(s):  
Nishant Modi ◽  
Bhargav Pandya ◽  
Jatin Patel
Keyword(s):  
Energy Source ◽  
Minimum Energy ◽  
Critical Energy ◽  
Maximum Energy ◽  
Coefficient Of Performance ◽  
Sodium Thiocyanate ◽  
Lithium Nitrate ◽  
Absorption Refrigeration ◽  
Evaporator Temperature ◽  
Source Temperature

Abstract This paper evaluates the energy source temperature for novel salts based ammonia/sodium thiocyanate (NH3 + NaSCN) and ammonia/lithium nitrate (NH3 + LiNO3) absorption refrigeration systems. Minimum energy source temperature (cutoff) required to initiate the cooling, critical energy source temperature for optimized thermodynamic performance and possible maximum energy source temperature to avoid crystallization have been determined, and empirical correlations are developed to facilitate continuous operation of the system. A comparison of cutoff energy source temperature depicts that the NH3 + NaSCN pair requires averagely 6 –7 °C higher cutoff temperature compared with the NH3 + LiNO3 pair. Contradictory to this, the maximum coefficient of performance (COP) of the NH3 + NaSCN pair is 7.02% higher than that the NH3 + LiNO3 pair. However, NH3 + NaSCN pair operates in a very narrow range of energy source temperature. From the P − T − X diagram, the crystallization phenomenon is clarified and the maximum energy source temperature has been determined beyond which the system would not function due to crystallization problems. For −10 °C evaporator temperature, the energy source temperature should be controlled between 87 °C and 115 °C for the NH3 + NaSCN pair and between 80 °C and 147 °C for the NH3 + LiNO3 pair.

Dynamic Performance Investigation of Single-Effect NH3 + LiNO3 and NH3 + NaSCN Solar Cooling Cycles: A Case Study for Western Indian Climate

2020 ◽  
Vol 142 (5) ◽  
Author(s):  
Nishant Modi ◽  
Bhargav Pandya ◽  
Vinay Kumar ◽  
Jatin Patel
Keyword(s):  
Dynamic Performance ◽  
Operating Conditions ◽  
Hot Water ◽  
Coefficient Of Performance ◽  
Sodium Thiocyanate ◽  
Lithium Nitrate ◽  
Ambient Conditions ◽  
Evaporator Temperature ◽  
Water Storage Tank ◽  
Single Effect

Abstract This article compares the dynamic behavior of solar-assisted novel salt-based ammonia/sodium thiocyanate (NH3 + NaSCN) and ammonia/lithium nitrate (NH3 + LiNO3) single-effect absorption refrigeration cycles. An evacuated tube collector (ETC) is attached with fully mixed hot water storage tank to power the absorption system. Variations in ambient conditions are determined for Gujarat Region of India and their effects on absorption cycles are quantified throughout the days for the months of April to September. System performance is investigated and compared on terms of coefficient of performance (COP), refrigeration capacity, efficiency and solar COP (SCOP). At same operating conditions, it is found that the NH3 + LiNO3 cycle can achieve much lower evaporator temperature (−13.1 °C) then NH3 + NaSCN cycle (−7.5 °C) and maximum possible COP for NH3 + NaSCN cycle is 0.73 and 0.68 for NH3 + LiNO3 cycle. The working limit of NH3 + LiNO3 cycle is wide ranging and narrow for NH3 + NaSCN cycle due to high crystallization possibility. SCOP varies from 0.18 to 0.43 for NH3 + NaSCN cycle and 0.17 to 0.39 for NH3 + LiNO3 cycle over the period of 6 months. Based on these findings, the suitable working cycle is justified.

Exergy analysis: Parametric study on lithium bromide—water absorption refrigeration systems

2007 ◽  
Vol 221 (11) ◽  
pp. 1345-1351 ◽  
Author(s):  
K Sedighi ◽  
M Farhadi ◽  
M Liaghi
Keyword(s):  
Exergy Analysis ◽  
Water Solution ◽  
Lithium Bromide ◽  
Cooling Water ◽  
Coefficient Of Performance ◽  
Absorption Refrigeration ◽  
Exergetic Efficiency ◽  
Evaporator Temperature ◽  
Cooling Water Temperature ◽  
Single Effect

In the current study, an exergy analysis of a single-effect absorption refrigeration cycle using lithium bromide-water solution is carried out. The cycle has been analysed by considering the mass and energy conservation based on the first and second laws of thermodynamics. This analysis provides a detailed information on the effect of different parameters on the system performance. The coefficient of performance (COP), exergetic efficiency (ECOP), and exergy destruction are determined. The results show that a reduction in cooling water temperature caused an improvement in the COP and ECOP. Increasing the evaporator temperature has also improved the COP, but it caused a reduction in the ECOP of the system. Also it can be seen that the parameters' variation at the solution side has a more significant effect on cycle performances.

Thermodynamic analysis of triple effect ammonia–water absorption compression (hybrid) cycle

2021 ◽  
pp. 095440892199568
Author(s):  
CP Jawahar
Keyword(s):  
Water Absorption ◽  
Energy Analysis ◽  
Cooling Capacity ◽  
Coefficient Of Performance ◽  
Working Fluid ◽  
Performance Parameters ◽  
Evaporator Temperature ◽  
Ammonia Water ◽  
Absorption Cycle ◽  
Hybrid Cycle

This paper presents the energy analysis of a triple effect absorption compression (hybrid) cycle employing ammonia water as working fluid. The performance parameters such as cooling capacity and coefficient of performance of the hybrid cycle is analyzed by varying the temperature of evaporator from −10 °C to 10 °C, absorber and condenser temperatures in first stage from 25 °C to 45 °C, degassing width in both the stages from 0.02 to 0.12 and is compared with the conventional triple effect absorption cycle. The results of the analysis show that the maximum cooling capacity attained in the hybrid cycle is 472.3 kW, at 10 °C evaporator temperature and first stage degassing width of 0.12. The coefficient of performance of the hybrid cycle is about 30 to 65% more than the coefficient of performance of conventional triple effect cycle.

Performance Characteristics of a Combined Ejector-Absorption Heat Pump Using NH3-H2O

1999 ◽  
Author(s):  
D. A. Kouremenos ◽  
E. D. Rogdakis ◽  
G. K. Alexis
Keyword(s):  
Heat Pump ◽  
Gain Factor ◽  
Coefficient Of Performance ◽  
Detailed Calculation ◽  
Absorption System ◽  
Evaporator Temperature ◽  
Pump System ◽  
Heat Gain ◽  
Absorption Heat Pump ◽  
Heat Pump System

Abstract Absorption system have been investigated for many years. However, coefficient of performance COP or heat gain factor HGF for absorption systems are significantly lower than those for conventional compression systems. This has restricted their wide application. This paper discusses the behavior of mixture NH3-H2O through of an ejector, operating in an absorption heat pump system. This combination improves the performance of conventional absorption system and with the phasing out of ozone-damaging refrigerants, absorption refrigerators, heat pumps and air-conditioning now provide a potential alternative. For the detailed calculation of the proposed system a method has been developed, which employs analytical functions describing the thermodynamic properties of die mixture. The influence of three major parameters: generator, condenser and evaporator temperature, on ejector efficiency and heat gain factor of the system is discussed. Also the maximum value of HGF was estimated by correlation of above three temperatures.

scholarly journals Absorption refrigeration system using engine exhaust gas as an energy source

2018 ◽  
Vol 12 ◽  
pp. 797-804 ◽  
Author(s):  
Sorawit Kaewpradub ◽  
Prawit Sanguanduean ◽  
Wattanapong Katesuwan ◽  
Nares Chimres ◽  
Phatthi Punyasukhananda ◽  
...  
Keyword(s):  
Energy Source ◽  
Exhaust Gas ◽  
Absorption Refrigeration ◽  
Refrigeration System ◽  
Engine Exhaust ◽  
Absorption Refrigeration System

scholarly journals Aerostatic Way of Harvesting High Altitude Wind Energy

2019 ◽  
Vol 8 (4) ◽  
pp. 7840-7844
Keyword(s):  
Energy Source ◽  
Renewable Energy ◽  
Wind Energy ◽  
Electrical Power ◽  
Energy System ◽  
Maximum Energy ◽  
Storage Device ◽  
Renewable Energy System ◽  
Important Field ◽  
Grid Storage

Renewable energy system in electrical power generation is one of important field of electrical engineering due to its source is natural, reusable and environmental pollution free and cost free. There are renewable energies such as wind, solar and so on. The wind is a free, clean, and inexhaustible energy source. It has served mankind well for many centuries by propelling ships and driving wind turbines to pump water. It has become one of the most attractive energy system in several decades due to rich availability. The important proposed contribution in this work is to enhance the efficiency of renewable energy using AEROSTATIC WAY OF HARVESTING WIND ENERGY that allows turbines to capture as much as possible wind by increase in the altitude at which is the turbine is placed. Which is done by attaching the turbine to aerostat and the aim of the study is to extract maximum energy of the turbine and transmit it to grid, storage device with suitable converters and controllers.

scholarly journals Generation of high energy laser-driven electron and proton sources with the 200 TW system VEGA 2 at the Centro de Laseres Pulsados

2019 ◽  
Vol 7 ◽  
Author(s):  
L. Volpe ◽  
R. Fedosejevs ◽  
G. Gatti ◽  
J. A. Pérez-Hernández ◽  
C. Méndez ◽  
...  
Keyword(s):  
Focal Length ◽  
Critical Energy ◽  
High Energy ◽  
Maximum Energy ◽  
Wake Field ◽  
Matter Interaction ◽  
User Access ◽  
Energy Laser ◽  
High Energy Laser ◽  
Operation Phase

The Centro de Laseres Pulsados in Salamanca, Spain has recently started operation phase and the first user access period on the 6 J 30 fs 200 TW system (VEGA 2) already started at the beginning of 2018. In this paper we report on two commissioning experiments recently performed on the VEGA 2 system in preparation for the user campaign. VEGA 2 system has been tested in different configurations depending on the focusing optics and targets used. One configuration (long focal length $F=130$ cm) is for underdense laser–matter interaction where VEGA 2 is focused onto a low density gas-jet generating electron beams (via laser wake field acceleration mechanism) with maximum energy up to 500 MeV and an X-ray betatron source with a 10 keV critical energy. A second configuration (short focal length $F=40$ cm) is for overdense laser–matter interaction where VEGA 2 is focused onto a $5~\unicode[STIX]{x03BC}\text{m}$ thick Al target generating a proton beam with a maximum energy of 10 MeV and temperature of 2.5 MeV. In this paper we present preliminary experimental results.

EXERGY ANALYSIS OF A LiBr–H2O VAPOR ABSORPTION REFRIGERATION PLANT: A CASE STUDY

2014 ◽  
Vol 22 (02) ◽  
pp. 1450010 ◽  
Author(s):  
SANJEEV ANAND ◽  
ANKUSH GUPTA ◽  
SUDHIR KUMAR TYAGI
Keyword(s):  
Performance Optimization ◽  
Exergy Analysis ◽  
Heat Rate ◽  
Exergy Efficiency ◽  
Exergy Loss ◽  
Absorption Refrigeration ◽  
Actual System ◽  
Evaporator Temperature ◽  
Vapor Absorption ◽  
Vapor Absorption Refrigeration

This communication presents the energy and exergy analysis of an actual double effect steam powered LiBr – H 2 O vapor absorption refrigeration plant. Exergy loss, COP, exergy efficiency and heat rate for each component of the system are calculated. The effect of generator as well as evaporator temperature on the COP and exergy efficiency is evaluated and it is found that the irreversibility rate is highest in the generator while it is found to be the lowest in the case of absorber and condenser. It is also found that the COP of the system increases with the increase in the evaporator temperature while it is found to be reverse in case of exergy efficiency. Results revealed that average exergy loss is highest in the generator as compared to other components. The results obtained are helpful for designers to bring changes in the actual system for performance optimization and less wastage of energy. The study clearly explain the operational and maintenance problems in the machine and point out the areas of energy wastage which the operational engineer should look into for the optimum operation of the plant.

Sign in / Sign up

Export Citation Format

Share Document