One of the essential components of an absorption air-conditioning/ heat pumping system is the absorber, where the refrigerant vapor is absorbed into the liquid solution. While absorption systems have been in use for several years, the processes occurring in the absorber, usually of the falling-film type, are not well understood and absorption rate equations are not well founded (developed), as they are for the other heat transfer processes present in absorption systems.

The objectives were to obtain sufficient experimental data on falling film absorption, that a correlation for the falling film absorption process could be developed. The specific requirements of the contract were to:
(a) complete the experimental apparatus that had largely been developed under prior University funding,
(b) obtain falling film experimental data for two refrigerant/ absorbent pairs, one being water/LiBr and the other to be specified by the monitoring committee,
(c) obtain data both without and with an additive,
(d) develop a correlation for falling film absorption based on the experimental data; and
(e) compare the experimental results with the numerical model for falling film absorption.