Thermoeconomic optimization of a single effect water/LiBr vapour absorption refrigeration system

2003 ◽  
Vol 26 (2) ◽  
pp. 158-169 ◽  
Author(s):  
R.D. Misra ◽  
P.K. Sahoo ◽  
S. Sahoo ◽  
A. Gupta
Author(s):  
Hugo Valença de Araújo ◽  
Luiz Henrique Parolin Massuchetto ◽  
Raiza Barcelos Corrêa do Nascimento ◽  
Stella Maia Rocha de Carvalho ◽  
José Vicente Hallak Dangelo

2018 ◽  
Vol 11 (No. 07) ◽  
pp. 363-368
Author(s):  
Guillermo Valencia Ochoa ◽  
Jorge Duarte Forero ◽  
Luis Obregon Quinones

Lubricants ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 76
Author(s):  
José Cabrera César ◽  
Jean Caratt Ortiz ◽  
Guillermo Valencia Ochoa ◽  
Rafael Ramírez Restrepo ◽  
José R. Nuñez Alvarez

A single effect LiBr–H2O absorption refrigeration system coupled with a solar collector and a storage tank was studied to develop an assessment tool using the built-in App Designer in MATLAB®. The model is developed using balances of mass, energy, and species conservation in the components of the absorption cooling system, taking into account the effect of external streams through temperature and pressure drop. The whole system, coupled with the solar energy harvesting arrangement, is modeled for 24 h of operation with changes on an hourly basis based on ambient temperature, cooling system load demand, and hourly solar irradiation, which is measured and recorded by national weather institutes sources. Test through simulations and validation procedures are carried out with acknowledged scientific articles. These show 2.65% of maximum relative error on the energy analysis with respect to cited authors. The environmental conditions used in the study were evaluated in Barranquilla, Colombia, with datasets of the Institute of Hydrology, Meteorology and Environmental Studies (IDEAM), considering multiannual average hourly basis solar irradiation. This allowed the authors to obtain the behavior of the surface temperature of the water in the tank, COP, and exergy efficiency of the system. The simulations also stated the generator as the biggest source of irreversibility with around 45.53% of total exergy destruction in the inner cycle without considering the solar array, in which case the solar array would present the most exergy destruction.


2021 ◽  
Author(s):  
Na Dong ◽  
Wenjin Lv ◽  
Shuo Zhu ◽  
Zhong-ke Gao ◽  
Celso Grebogi

Abstract Based on the model-free adaptive control (MFAC) theory, the temperature tracking control problem of single-effect LiBr/H 2 O absorption chiller is explored. Due to the complex nonlinearity and strong coupling characteristics of the absorption refrigeration system, model-free adaptive control strategy is designed for its temperature tracking control. Nevertheless, the traditional model-free adaptive control has a slow tracking speed and poor denoising ability. In order to improve its control effect, output error rate is added to the objective function and new control laws of model-free adaptive control with output error rate (MFAC-OER) have been derived through an exhaustive convergence and stability analysis. The input and output information of the absorption refrigeration system, namely the hot water pump frequency and frozen water outlet water temperature, are combined. The data model of the absorption refrigeration system is subsequently deduced using a compact format dynamic linearization method. Next, based on the single effect absorption chiller experimental platform in our laboratory, its sixth-order dynamic model is built. Finally, the effectiveness and practicability of the improved control strategy are validated by numerical simulations and experimental operating data from our laboratory as well as by the dynamical model of the absorption chiller.


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