Experimental heat and mass transfer studies on horizontal falling film absorber using water-lithium bromide

Abstract

Vapour absorption systems are more viable technology option in energy and environmental perspective in cooling and heating applications. Among the four major components of vapour absorption system, the absorber plays a vital role in deciding the performance, size and cost. Horizontal falling film absorbers comparatively contain good heat and mass transfer characteristics than other type of absorbers for working fluids such as water-lithium bromide. Literature shows that experimental approach of performance evaluation of absorber is more realistic and accurate than the theoretical approach. Hence in the present work, a detail experimental study has been done on horizontal tube falling film absorber using water-lithium bromide as a working fluid. The set-up consists of two major components viz. absorber and generator. Absorber contains three columns of tubes, with eight rows in each column. Detailed parametric study has been done by considering influence of spray density, cooling water-flow rate, cooling water temperature and concentration on solution temperatures, cooling water temperatures, inlet and outlet concentrations, heat flux, mass flux, heat transfer coefficient, and mass transfer coefficient with the help of plots. Results have been validated and literature gaps have been discussed.