Thermodynamic limits to thermal regeneration in adsorption cooling cycles

Energy and exergy models for ideal adsorption cycles with isothermal beds and no mass recovery are developed to predict the limits to COP enhancement using thermal regeneration. The models are applied to compare the performance of zeolite-water and silica gel-water adsorbent-refrigerant pairs over a range of maximum bed temperatures. The thermodynamic consistencies of several alternate adsorption property assumptions are quantified. Differences in adsorption characteristics between zeolite-water and silica gel-water result in a significantly larger potential to enhance COP by implementing thermal regeneration for zeolite-water. Based on COP, the zeolite-water pair is preferred when both thermal regeneration and a high temperature thermal energy source (>150 degrees C) are used, while the silica gel-water pair is preferred when thermal regeneration is not used and/or a low temperature thermal energy source (<100 degrees C) is used. (c) 2007 Elsevier Ltd and IIR. All rights reserved.


Numerical simulation and analytical optimization of microchannel heat sinks
Türkakar, Göker; Okutucu Özyurt, Hanife Tuba; Department of Mechanical Engineering (2010)
This study has two main objectives: The performance evaluation of existing microchannel heat sinks using a CFD model, and the dimensional optimization of various heat sinks by minimizing the total thermal resistance. For the analyses, the geometric modeling is performed using the software GAMBIT while the thermal analysis is performed with FLUENT. The developed model compares very well with those available in the literature. Eight different metal-polymer microchannel heat sinks are analyzed using the model ...
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The accuracy of the finite element method and strip method of analysis for calculating the lateral stiffness of steel plate shear wall (SPSW) systems is assessed by making comparisons with experimental findings. Comparisons revealed that while both methods provide acceptable accuracy, they also require the generation of sophisticated computer models. In this paper, two alternative methods are developed. The first one is an approximate hand method based on the deep beam theory. The classical deep beam theory...
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Citation Formats
D. K. Baker, “Thermodynamic limits to thermal regeneration in adsorption cooling cycles,” INTERNATIONAL JOURNAL OF REFRIGERATION-REVUE INTERNATIONALE DU FROID, pp. 55–64, 2008, Accessed: 00, 2020. [Online]. Available: