Modelling of an adsorption chiller with adsorbent-coated heat exchangers: Feasibility of a polymer-water adsorption chiller

An analytical model is developed for an adsorption chiller with adsorbent-coated heat exchangers, where adsorbent is deposited on heat exchanger surface in thin film to improve heat and mass transfer characteristics. Approximate solutions are obtained from the simplified governing equations for the heat exchanger and then used to predict performance of the chiller. The analytical model provides the heat and mass fluxes in the system in explicit functions of a few dimensionless numbers including Nt, Ja, γ and Cr. The analytical model is validated via comparison with a two-dimensional numerical model in wide ranges of design and operating parameters. The maximum discrepancy is found ca. 13% in SCP and 0.02 point in COP. Performance of the chiller is discussed regarding the influences of various design and operating parameters. Some experimental results are also analyzed with the analytical model and the results are discussed focusing on the performance of polymer-coated heat exchangers.