Temporal exergy analysis of adsorption cooling system by developing non-flow exergy function

Abstract In this paper, it is performed temporal exergy analysis of an adsorption cooling system in which the durations of desorption and adsorption phases are different. For this purpose, a non-flow exergy function is proposed for substituting the general exergy balance equation. Considering that, temporal irreversibility in adsorption beds, condenser, evaporator, and expansion valve, and also the irreversibility due to external thermal coupling, are calculated. The temporal exergy analysis showed that the maximum rate of irreversibility has occurred in the beginning of precooling and preheating processes. The overall exergy analysis revealed that adsorption beds, thermal coupling, and adsorption cycle components are in charge of 77%, 16% and 7% of total irreversibility, respectively. Moreover, results showed that the intensity of irreversibility in preheating and precooling processes is more than the intensity of irreversibility in adsorption and desorption processes. However, the average per-cycle irreversibility in switching time are less than average per-cycle irreversibility in adsorption and desorption duration. Exergy analysis also showed that increasing heat source temperature will enhance irreversibility in cycle components, and this increase is more sensible in adsorption beds.

[1]  A. Bejan.  The Concept of Irreversibility in Heat Exchanger Design: Counterflow Heat Exchangers for Gas-to-Gas Applications , 1977 .

[2]  K. Wark,et al.  Advanced thermodynamics for engineers , 1994 .

[3]  C. Muraleedharan,et al.  Exergy Assessment of Single Stage Solar Adsorption Refrigeration System Using ANN , 2012 .

[4]  Takahiko Miyazaki,et al.  A new cycle time allocation for enhancing the performance of two-bed adsorption chillers , 2009 .

[5]  Hui Tong Chua,et al.  A comparative evaluation of two different heat-recovery schemes as applied to a two-bed adsorption chiller , 2007 .

[6]  M. Feidt,et al.  Numerical Results on Operating Parameters Influence for a Heat Recovery Adsorption Machine , 2011 .

[7]  P. Webley,et al.  Application of an adsorption non-flow exergy function to an exergy analysis of a pressure swing adsorption cycle , 2004 .

[8]  Akiyoshi Sakoda,et al.  FUNDAMENTAL STUDY ON SOLAR POWERED ADSORPTION COOLING SYSTEM , 1984 .

[9]  M. Pons.  Analysis of the adsorption cycles with thermal regeneration based on the entropic mean temperatures , 1997 .

[10]  Giovanni Restuccia,et al.  Selective water sorbents for multiple applications, 1. CaCl2 confined in mesopores of silica gel: Sorption properties , 1996 .

[11]  Ahmed Hamza H. Ali,et al.  An overview on adsorption pairs for cooling , 2013 .

[12]  Kyaw Thu,et al.  Entropy generation analysis of an adsorption cooling cycle , 2013 .

[13]  Francis Meunier,et al.  Second-law analysis of adsorptive refrigeration cycles: The role of thermal coupling entropy production , 1997 .

[14]  Takahiko Miyazaki,et al.  The influence of heat exchanger parameters on the optimum cycle time of adsorption chillers , 2009 .

[15]  Pierre Neveu,et al.  A comparative thermodynamic study of sorption systems: second law analysis , 1996 .

[16]  M. Bahrami,et al.  Critical analysis of thermodynamic cycle modeling of adsorption cooling systems for light-duty vehicle air conditioning applications , 2015 .

[17]  Irene P. Koronaki,et al.  Thermodynamic modeling and exergy analysis of a solar adsorption cooling system with cooling tower in Mediterranean conditions , 2016 .

[18]  A. Freni,et al.  Reallocation of adsorption and desorption times for optimisation of cooling cycles , 2012 .