Using a simple model for falling film absorption to identify crucial absorbent properties

Abstract

Consulta en la Biblioteca ETSI Industriales (9154)

[EN] In this Final Master Thesis some properties of the working pairs used in absorbers as a part of cooling systems has been studied to optimize its values. To achieve reliable results, a model based the work of Wohlfeil and Auracher for falling films in horizontal tubes has been developed. The model consists in an absorber with horizontal tubes and an aqueous solution of lithium bromide used as absorbent and water as a coolant. After checking the calculations comparing the data with other similar models, the thermal conductivity, mass diffusivity and viscosity of the absorbent solution are changed, to analyze the effect of every of these variables and maximize the mass flux absorbed by the system. With the results obtained it has been possible to describe the preference order of the properties mentioned before to establish a criterion when selecting a possible new working pair of liquids for an absorber by its predicted behavior, without experimentation needed.