Effects of plate finned heat exchanger parameters on the adsorption chiller performance

摘要

In this paper the performance of an adsorption chiller working with water and the composite sorbent SWS-1L known for high coefficient of performance (COP) in unites driven by low temperature heat has been examined. A three-dimensional non-equilibrium numerical model describing the combined heat and mass transfer in an adsorbent bed with plate fins is presented. The spatial variations of pressure and gas flow inside the bed along with the internal and external resistances of bed particles are considered. Flow patterns and pressure distributions though out the bed are examined in detail for all cycle phases. The effects of important bed configurations such as fins spacing and height on the system performance are studied. Furthermore, a detailed investigation of the share of each part of the system from the input energy during the heating phase is presented for different fins heights and spaces. It was found that the geometric specifications of the adsorption heat exchanger are of great practical importance in designing adsorption cooling systems such that systems with either higher COP or higher specific cooling power may be considered as the appropriate choice depending on the cost of input energy to the cooling system. Furthermore, at the cost of slightly lower COP, the size of the system and therefore, the initial cost of the system can be reduced considerably.