Exergy calculation of lithium bromide-water solution and its application in the exergetic evaluation of absorption refrigeration systems LiBr-H2O

2010 ◽  
Vol 36 (2) ◽  
pp. 166-181 ◽  
Author(s):  
Reynaldo Palacios-Bereche ◽  
R. Gonzales ◽  
S. A. Nebra
Keyword(s):  
Water Solution ◽  
Lithium Bromide ◽  
Absorption Refrigeration

Effect of Ejector Location in Absorption Refrigeration Cycles Using Different Binary Working Fluids

2019 ◽  
Vol 27 (01) ◽  
pp. 1950003 ◽  
Author(s):  
Salem Yosaf ◽  
Hasan Ozcan
Keyword(s):  
Performance Enhancement ◽  
Water Solution ◽  
Lithium Bromide ◽  
Cycle Performance ◽  
Refrigeration Cycle ◽  
Absorption Refrigeration ◽  
Working Fluids ◽  
Steam Ejector ◽  
Thermodynamic Performance ◽  
Chloride Water

In this study, three novel modifications of ejector-absorption refrigeration cycles (E-ARC) are investigated to evaluate the effect of ejector location on cycle performances. In the first modification (triple pressure level absorption refrigeration cycle TPL-ARC), the ejector is located at the evaporator inlet. In the second modification (double ejector absorption refrigeration cycle DE-ARC), two ejectors are used; one is located at the evaporator inlet and the other at the absorber inlet, which are coupled to each other. In the third modification (low pressure condenser absorption refrigeration cycle LPC-ARC), the steam ejector is installed at the downstream of the vapor generator discharging line. An additional flow splitter is integrated to the steam ejector outlet and part of the vapor is extracted and returned to the absorber at a pressure equal to the diffuser pressure. Effect of ejector location on thermodynamic performances are evaluated considering three different working fluids, namely ammonia–water solution (NH3–H2O), lithium bromide-water solution (H2O–LiBr), and lithium chloride–water solution (H2O–LiCl). Even though all three configurations enhance the conventional absorption refrigeration cycle (C-ARC) performances, the LPC-ARCs work at high temperature and improve the cycle performance. The TPL-ARC proves to improve the COP and exergy efficiency up to 9.14% and 7.61%, respectively, presenting the highest thermodynamic performance enhancement and lowest operating temperature.

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.

scholarly journals Modeling of conjugated heat and mass transfer in the entrance region of falling liquid film at various values of the Froude number

2018 ◽  
Vol 194 ◽  
pp. 01007
Author(s):  
Maria V. Bartashevich
Keyword(s):  
Heat Transfer ◽  
Mass Transfer ◽  
Liquid Film ◽  
Froude Number ◽  
Heat And Mass Transfer ◽  
Water Solution ◽  
Lithium Bromide ◽  
Entrance Region ◽  
Falling Film ◽  
Falling Liquid Film

Mathematical model of conjugated heat and mass transfer in absorption on the entrance region of the semi-infinite liquid film of lithium bromide water solution is investigated for different values of Froude number. The calculations shown that larger values of Froude number corresponds to a smaller thickness of the falling film. It was demonstrated that for large values of the Froude number the heat transfer from the surface is greater than for smaller values.

scholarly journals Absorption of water vapor into a lithium bromide water solution film falling along a vertical plate.

1987 ◽  
Vol 53 (485) ◽  
pp. 236-240 ◽  
Author(s):  
Itsuki MORIOKA ◽  
Masanori KIYOTA
Keyword(s):  
Water Vapor ◽  
Vertical Plate ◽  
Water Solution ◽  
Lithium Bromide

scholarly journals Absorption of water vapor into lithium bromide-water solution film falling along a vertical plate.

1986 ◽  
Vol 52 (476) ◽  
pp. 1766-1771 ◽  
Author(s):  
Kazuma URAKAWA ◽  
Itsuki MORIOKA ◽  
Masanori KIYOTA
Keyword(s):  
Water Vapor ◽  
Vertical Plate ◽  
Water Solution ◽  
Lithium Bromide

scholarly journals TESTS OF ARRANGEMENTS IN A PROTOTYPE OF A STEAM GENERATOR IN AN ABSORPTION REFRIGERATION SYSTEM

2019 ◽  
Vol 18 (2) ◽  
pp. 70
Author(s):  
R. F. M. Santos ◽  
K. L. Cezar ◽  
P. A. C. Rocha ◽  
R. J. P. Lima ◽  
M. E. V. da Silva ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Steam Generator ◽  
Lithium Bromide ◽  
Heat Transfer Process ◽  
Heat Flow Rate ◽  
Absorption Refrigeration ◽  
Refrigeration System ◽  
Governing Factor ◽  
Absorption Refrigeration System ◽  
Internal Convection

This paper presents a proposal to optimize the prototype II of a steam generator, developed by the Cooperativa de Pesquisa Norte/Nordeste de Gas Natural, RECOGÁS - UFPB, which is a component of an absorption refrigeration system of water and lithium bromide triggered by direct burning of natural gas. The optimization was carried out through changes in the arrangement, geometry, and number of the heat exchanger pipes. It was developed a computational code using F-Chart software Engineering Equation Solver® (EES), applying the principles of heat transfer to all the different geometries. As a result, their respective coefficients of heat transfer, heat flow rate and other parameters of the process were obtained. The findings are organized in a table and represented in graphs generated by the EES software, allowing to verify which factors had a greater influence on the process, as well as the most efficient geometries. Internal convection was identified as the governing factor in the heat transfer process. Some of the geometries presented satisfactory values to the product of overall heat transfer coefficient and surface area (UA) and also to the heat transfer rate in the steam generator. Other ones presented a better thermal efficiency relation with the amount of volume occupied in the steam generator. Some geometries did not present satisfactory values under any aspect.

Sign in / Sign up

Export Citation Format

Share Document