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Adsorption cooling system is driven by low‐grade heat sources and is an eco‐friendly system, is therefore considered a potential alternative to the traditional vapor‐compression refrigeration system. An exergy analysis is a tool for identifying the details of energy degradation of each process and component, but there is a critical limitation in previous works which assumed there was no spatial variation in the adsorption beds, i. e. the lumped capacity method. We have conducted both an energy and exergy analysis of an adsorption cooling system. The exergy analysis was conducted based on detailed information obtained from the CFD results of energy analysis. The numerical results provide detailed information which varies in time and space, free of the assumptions used in lumped capacity methods, by including the effects of geometric features (fin height, fin spacing, tube diameter, and thickness) and, the contact resistance between sorbent material and metallic finned tube, which affirmatively enhance the accuracy of the exergy analysis. Finally, we analyze the effect of several main parameters from the view point of the 2nd law of thermodynamics. The results show that increases in the temperature of the heat sources leads to an increase in energy performance while the exergy efficiency decreases; increases in the cooling water temperature reduces the COP, SCP, and ηex. An increase in cycle time improves the COP and ηex but reduces the SCP. The exergy analysis was conducted based on detailed information obtained from the CFD results of energy analysis. The numerical results provide detailed adsorption bed information which varies in time and space, free of the assumptions used in lumped capacity methods. The effect of several main parameters on system performance from the view point of the 2nd law of thermodynamics was discussed, herein. [ABSTRACT FROM AUTHOR]

Abstract: A numerical simulation of the performance of a fin‐tube‐type adsorption bed with silica gel/water working pairs was conducted. Three models of the heat recovery cycle, the mass recovery cycle, and a combined heat and mass recovery cycle were closely examined. The main goals were to determine 1) the conditions under which these advanced cycles were most effective and 2) the optimum recovery time. Mass recovery enhanced both the coefficient of performance (COP) and specific cooling power (SCP) by up to 24 and 37.5 %, respectively, at 60 °C, and the enhancements of the COP and SCP were 5.0 and 16.0 %, respectively, at 90 °C. Heat recovery increased the COP by 12.56 %, but reduced the SCP by 10.84 % at 60 °C, whereas, at 90 °C, the COP increased by 11.83 % and SCP decreased by 5.96 %. The mass recovery is more influential at a low heating temperature than that at a high heating temperature. Therefore, in the combined heat and mass recovery cycles, the main contribution to the enhancement of the COP comes from mass recovery at lower water temperature. However, at a high heating temperature, the COP increases mainly due to heat recovery. [ABSTRACT FROM AUTHOR]