One dimensional versus two dimensional heat and mass transfer modeling of cylindrical sorption cells

Efficient heat and mass transfer analyses are essential for the development of advanced thermal systems. The efficiency of a numerical model is determined by its accuracy, range of validity, simplicity, computational resource requirements, and running time. An adequate balance among these contradicting characteristics yields an effective model, which provides valuable results during the design procedure of sophisticated thermal systems. Sorption systems frequently operate in thermal cycles, and usually include heat transfer in porous materials, incorporating internal heat generation and absorption. In previous research, we introduced a one-dimensional numerical model of sorption compressors, which is validated against experimental results. The aim of the model is to allow extensive parametric investigations of sorption systems, due to its short running time. This one-dimensional model incorporates three fitting parameters, which are design dependent, to compensate for the axial heat transfer at the cells’ edges. In the current research, we present a further successful validation of this numerical model against a two-dimensional numerical model, which enables to determine the three fitting parameters of the one-dimensional model. The two-dimensional model does not require any fitting parameters. It is obviously much easier than preparing additional experimental apparatuses, although its running time is dramatically longer relative to the one-dimensional model. The results prove that increasing the length over diameter ratio of the sorption cell increases the fitting parameter; that is, the one-dimensionality assumption becomes more realistic. This study shows the advantages of a simplified, fast responding model, which can be effectively used during a design process of complex systems.