Study of the fundamentals of adsorption systems

In the design of adsorption refrigeration/heat pump systems, the characteristics of both adsorbent-adsorbate (refrigerant) pairs and adsorption cycles play an important role in various kinds of applications. The description of the performance of the adsorption-desorption process involves different modeling techniques with various simplifications, and the corresponding results are significantly different. In this paper, a thermal model based on the Dubinin-Radushkevich equation and thermodynamic analyses is given, which presents a complete and precise description of adsorption-desorption cycles. In the model, variable physical properties with temperature, such as specific heat of working pairs, isosteric heat of desorption or adsorption, are particularly considered, several main factors affecting the performance of cycles are discussed according to the results of computer simulations, such as the characteristics of working pairs and the working conditions, especially the heat capacities of generators. The relationship between the performance of the cycles and these factors is initially investigated. The performances of advanced cycles, such as the heat regenerative adsorption cycle, are also analyzed and compared with that of the basic adsorption cycle. Copyright (C) 1997 Elsevier Science Ltd.