A Thermodynamic Performance Analysis of Triple Effect Vapour Absorption Refrigeration System Using LiBr-H2O

Abstract: Being an eco-friendly system and a cheaper way to produce cooling effect absorption refrigeration system (ARS) is becoming more popular as it can produce higher cooling capacity than vapor compression refrigeration systems, and it can be powered by other sources of energy (like waste heat from gas and steam turbines, or can utilizes renewable source of heat by sun, geothermal, biomass) other than electricity. In the recent years, the interest in absorption refrigeration system is growing because these systems have environmentally friendly refrigerant and absorbent pairs. In this study, a detail energetic analysis of triple stage LiBr-H20 absorption system using First law of thermodynamics is done. An Energy Equation Solver code are used to simulate the computer program is developed for the cycle and results are validated with past studies available is also done. Mass, energy and exergy balance equations and the various complementary relations constitute the simulation model of the triple effect refrigeration system. Further, the effect of exit temperature of generator, absorber, condenser and evaporator on COP, solution concentration and other parameters are studied. It was found in the study that COP increases with increasing the generator exit temperature keeping the absorber exit temperature constant but when the absorber exit temperature is increased COP tends to decrease and the concentration of weak solution leaving HP generator (Xw3), MP generator (Xw2) and LP generator (Xw1) also increases with increase in generator exit temperature, while it decreases with increase in condenser exit temperature. Keywords: Absorption Refrigeration System (ARS), LiBr + H2O, COP, solution concentration, Energy Equation Solver code, energetic analysis, triple effect refrigeration system.

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Design and construction of a low capacity pump-less absorption system

Thermal Science ◽

10.2298/tsci120119016m ◽

2014 ◽

Vol 18 (2) ◽

pp. 577-590

Author(s):

Hamed Monsef ◽

Naghash Zadegan ◽

Koroush Javaherdeh

Keyword(s):

Electrical Power ◽

Solution Concentration ◽

Absorption Refrigeration ◽

Refrigeration System ◽

Absorption System ◽

Horizontal Tubes ◽

Mechanical Pump ◽

Absorption Refrigeration System ◽

The Cost ◽

Bubble Pump

In this investigation, a low capacity absorption system has been designed and constructed where the mechanical pump has been replaced with a bubble pump, reducing the cost and eliminating the electrical power. Initially, a test rig bubble pump has been built with a single Pyrex tube to test the effect of different parameters on pumping flow rate. An absorption refrigeration system with a capacity of 2.5 kW has been designed and constructed. Results have shown that a bubble pump with five horizontal tubes with 2.5 mm diameter and submergence ratio of 0.4 has the best performance for this low capacity absorption refrigeration system. The COP of this structure was about 0.51 and mathematical modeling shows that increasing the solution concentration at generator outlet decreases the COP of the system.

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Thermodynamic Assessment of Waste Heat Operated Combined Compression–Absorption Refrigeration System

Progress in Exergy, Energy, and the Environment ◽

10.1007/978-3-319-04681-5_17 ◽

2014 ◽

pp. 193-205

Author(s):

Abdul Khaliq ◽

Ibrahim Dincer

Keyword(s):

Thermodynamic Assessment ◽

Waste Heat ◽

Absorption Refrigeration ◽

Refrigeration System ◽

Absorption Refrigeration System

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Thermal Energy Requirements of Air-Conditioning Systems

Journal of Engineering for Power ◽

10.1115/1.3445548 ◽

1971 ◽

Vol 93 (2) ◽

pp. 172-176

Author(s):

M. E. Lackey

Keyword(s):

Thermal Energy ◽

Air Conditioning ◽

Waste Heat ◽

Energy Requirements ◽

Absorption Refrigeration ◽

Refrigeration System ◽

Fast Breeder Reactors ◽

Breeder Reactors ◽

Absorption Refrigeration System ◽

Air Conditioning Systems

The thermal energy requirements for air conditioning by compressive and absorption methods were determined for light-water, thermal-breeder, and fast-breeder reactors. The energy required to produce a ton-hour of refrigeration varied from 5100 Btu to 13,100 Btu by absorption and from 5600 to 8800 Btu by compression. The amount of waste heat dissipated to the environment at the reactor site as a consequence of producing a ton-hour of air conditioning ranged from an increase of 21,000 Btu for the electric-motor-driven refrigeration system to a decrease of 6000 Btu for the absorption refrigeration system.

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Experimental Analysis of a Laboratory-Scale Diesel Engine Exhaust Heat-Driven Absorption Refrigeration System as a Model for Naval Surface Ship Applications

Journal of Ship Production and Design ◽

10.5957/jspd.2020.36.2.152 ◽

2020 ◽

Vol 36 (02) ◽

pp. 152-159 ◽

Cited By ~ 1

Author(s):

Cüneyt Ezgi ◽

Sinem Bayrak

Keyword(s):

Diesel Engine ◽

Experimental Analysis ◽

Alternative Energy ◽

Cooling Capacity ◽

Energy Sources ◽

Naval Academy ◽

Absorption Refrigeration ◽

Refrigeration System ◽

Exhaust Heat ◽

Absorption Refrigeration System

Decreasing industrial energy sources and major environmental problems caused by uncontrolled energy consumption have led to studies on alternative energy sources. This study presents a design and experimental analysis of an exhaust gas-driven absorption refrigeration system for the purpose of air conditioning by using the exhaust heat of a diesel engine, which is installed in the Naval Academy Mechanics Laboratory. The diesel engine is loaded with a dynamometer, and water and ammonia are used as an absorbent and refrigerant, respectively. At various diesel engine loads, cooling capacity and coefficient of performance (COP) of the absorption refrigeration system are calculated. Experimental results have indicated the cooling capacity as 1.098 kW at a maximum engine power of 4.9 HP. The highest COP value in the designed system has been calculated to be .3022 for the generator temperature of 160 C. Although the COP of refrigeration is low, the absorption refrigeration system can be provided a great cooling load from the exhaust heat of diesel engines and can be used in naval surface ships. In addition to energy efficiency of naval surface ships, infrared and acoustic signature can be minimized and a ships susceptibility can be dramatically reduced.

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Application of waste heat powered absorption refrigeration system to the LNG recovery process

International Journal of Refrigeration ◽

10.1016/j.ijrefrig.2009.01.029 ◽

2009 ◽

Vol 32 (4) ◽

pp. 687-694 ◽

Cited By ~ 57

Author(s):

Paul Kalinowski ◽

Yunho Hwang ◽

Reinhard Radermacher ◽

Saleh Al Hashimi ◽

Peter Rodgers

Keyword(s):

Waste Heat ◽

Recovery Process ◽

Absorption Refrigeration ◽

Refrigeration System ◽

Absorption Refrigeration System

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Experimental analysis of absorption refrigeration system driven by waste heat of diesel engine exhaust

Thermal Science ◽

10.2298/tsci160311003k ◽

2019 ◽

Vol 23 (1) ◽

pp. 149-157

Author(s):

Mukul Kumar ◽

Randip Das

Keyword(s):

Diesel Engine ◽

Waste Heat ◽

Combustion Engine ◽

Engine Performance ◽

Exhaust System ◽

Bench Test ◽

Exhaust Gas ◽

Absorption Refrigeration ◽

Refrigeration System ◽

Absorption Refrigeration System

This work presents an experimental study of an ammonia-water absorption refrigeration system using the exhaust of an internal combustion engine as energy source. The exhaust gas energy availability, the performance of the absorption refrigeration system and the engine performance are evaluated. A commercial turbocharged Diesel engine has been tested in a bench test dynamometer, with the absorption refrigeration system adapted to the exhaust system. The maximum COP obtained from the refrigeration system is 0.136 and it has been shown that heat energy available with exhaust gas is capable of producing sufficient cooling capacity for air conditioning the vehicle without requiring any energy input from the engine.

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Thermal Analysis of a Forced Flow Diffusion Absorption Refrigeration System for Fishing-Boat Exhaust Waste Heat Utilization

Frontiers in Energy Research ◽

10.3389/fenrg.2021.761135 ◽

2021 ◽

Vol 9 ◽

Author(s):

Shuai Du

Keyword(s):

Thermal Analysis ◽

Waste Heat ◽

Forced Flow ◽

The Novel ◽

Absorption Refrigeration ◽

Refrigeration System ◽

Fishing Boat ◽

Exhaust Waste Heat ◽

Absorption Refrigeration System ◽

Diffusion Absorption

Ammonia water absorption refrigeration systems are effective in utilizing fishing-boat exhaust waste heat for cryopreservation. However, the liquid level control and the use of a solution pump characterized by small flowrate and high-pressure head result in poor reliability in the traditional system. Besides, the system must necessarily be designed anti-swaying and anti-corrosion. This paper proposes a forced flow diffusion absorption refrigeration system, in which an inherently leak-free canned motor pump and an ejector are employed to provide the driving forces of the gas and liquid loops. The approximate single pressure operation allows for a simple passive liquid sealing control without throttling valves. The system adopts an integrated cooling strategy which allows the system to operate under swaying conditions, and the external seawater cooled heat exchanger avoids internal corrosion and leakage. The thermal analysis shows the system is valid to be operated under wide operating conditions, and the coupled gas and solution circulation ratios determined the performance of the novel system. There is an optimal ammonia mass fraction difference in the gas loop to obtain the optimal COP. The COP reaches 0.4 when the temperatures at the outlets of the generator, evaporator, absorber, and condenser are 160, −15, 35, and 35°C, respectively. The novel system provides a reliable absorption refrigeration system design for fishing-boat applications.

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