In recent years, using fossil fuels has increased due to population growth which leads to an increase in global concerns about environmental problems. Hence adsorption chiller systems have attracted much attention because of utilizing renewable and clean energies such as solar and geothermal ones and employing non-toxic refrigerants. In spite of mentioned advantages, poor heat and mass transfer in adsorption systems make them fall behind traditional vapor compression ones in global marketing. Thermal contact resistance between the adsorbent granules and thermal surfaces (metal tube and fins) impairs the adsorption performance by decreasing the coefficient of performance and specific cooling power. Therefore, in this paper, a transient three-dimensional non equilibrium numerical model is presented to evaluate the effect of thermal contact resistance on the performance of adsorption chillers. The spatial variations of pressure and gas flow inside the bed along with the internal and external mass transfer resistances have been considered in this modeling. The developed model is validated against the available experimental data in literature. As the results show, thermal contact resistance affects the heat and mass transfer in adsorbent bed and the cycle time decreases as a result of contact resistance elimination. Also it is found that the cooling and heating capacities increase by applying zero thermal contact resistance which is larger in quantity for the cooling capacity. Finally it is observed that the coefficient of performance and the specific cooling power improves when the thermal contact resistance is equal to zero.

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