Numerical modeling of combined heat and mass transfer in the adsorbent bed of a zeolite/water cooling system

A zeolite-13X/water adsorption-cooling system based on cylindrical double-tube adsorbent beds, heated or cooled by an external fluid is studied numerically. A two-dimensional non-equilibrium numerical model describing the combined heat and mass transfer in adsorbent bed is presented. As the performance of this system is mainly influenced by the heat and mass transfer properties, three sub-models of heat and mass transfer properties (gas flow in adsorbent bed model, lineal force driven model and equivalent heat transfer conductivity of adsorbent bed model) of the adsorbent bed are proposed in this model. The effect of main configuration parameters such as the heat and mass transfer coefficients, thickness of the bed, diameter of the particle and porosity, on the thermal performance of the system are investigated. It is found that the performance can be strongly influenced by the adsorbent thickness and porosity of the adsorbent bed, while the variation of particle size has minimal effect on the performance. Furthermore, the effect of generation temperature on thermal performance was also investigated.