Simulation of water sorption dynamics in adsorption chillers

This paper presents a mathematical model of coupled heat and mass transfer in multi-layers of loose adsorbent grains under realistic adsorption cooling cycle conditions. The model was applied to simulate nonisothermal water adsorption in a single grain and through a two-grains configuration of adsorbent Fuji silica type RD (grain size 0.45 mm), subjected to a fast variation of temperature. The model was successfully validated by means of experimental data obtained by a Large Temperature Jump (LTJ) method. Results obtained showed that, in the investigated conditions, the water adsorption is noticeably faster for the monolayer of silica gel grains because of the more efficient heat transfer to/from the adsorbent.