Numerical investigation of coupled heat and mass transfer inside the adsorbent bed of an adsorption cooling unit

In this study, the influence of several design parameters on the transient distributions of temperature, pressure and amount adsorbed in the radial direction of a cylindrical adsorbent bed of an adsorption cooling unit using silica gel/water have been investigated numerically. For this purpose, a transient one-dimensional local thermal non-equilibrium model that accounts for both internal and external mass transfer resistances has been developed using the local volume averaging method. For the conditions investigated, the validity of the local thermal equilibrium and spatially isobaric bed assumptions have been confirmed. To improve the performance of the bed considered, efforts should be focused on reducing heat transfer resistances and intra-particle (interior) mass transfer resistances but not inter-particle (exterior) mass transfer resistances.

► Heat and mass transfer conditions in the adsorbent bed were studied numerically.
► Silica-gel/water was used as working pair in a cylindrical adsorbent bed.
► A transient one-dimensional local thermal non-equilibrium model was developed.
► The model accounts for both internal and external mass transfer resistances.
► The thermal equilibrium model assumption was investigated.