Design and development of an automated absorption calorimeter system

Abstract

A microcomputer controlled absorption calorimeter has been designed and constructed for data acquisition in solar energy conversion measurements and tested by taking measurements on surfaces of specimens of selected metals; copper and aluminium. The BBC microcomputer with its versatile interface ports has been used. The instrument has been tested by determining the heating and cooling curves of the surfaces of samples prepared from the materials that can potentially be used for constructing solar collector plates. From the measurements, the radiation absorption characteristics of the surfaces can be qualitatively deduced. The absorptances of two of the metals used: copper and aluminium coated with soot have been determined based on values of absorptance of the pure metals obtained from literature. The values calculated using intervals of temperature from different parts of the graphs have been found to be • constant, which is in agreement with the fact that the absorptance is a constant.