Accounting for the real properties of the heat transfer fluid in heat-regenerative adsorption cycles for refrigeration

Adsorption cycles for refrigeration or heat pumping can be environmentally friendly. Moreover, when they use the process of heat-regeneration, they can be energetically efficient provided the adsorbers are correctly designed, which requires correct modelling. In such a model, all the heat exchanges undergone by the heat transfer fluid are considered. The temperature changes of this fluid induce variations in its physical properties. The influence of these variations on the cycle performance are numerically investigated and thermodynamically analysed. The effects of the changes in density are negligible, but those of the changes in heat capacity cannot be neglected. The analysis shows that this result is due to the interdependence of all the heat quantities involved in the cycle via the first principle of thermodynamics.