Measurement and Prediction of Absorbed Irradiation Energy Distribution in Narrow Channel of Desiccant Rotor

Abstract

The objective of this paper is to present experimental results on absorption characteristics of irradiation energy absorbed on the narrow channel wall of a regenerated desiccant rotor. Energy absorption rate was measured in conditions of different channel lengths, incident irradiation angles, temperatures and humidity. The results indicated no influence of ambient temperature and humidity on energy absorption rate, and showed symmetry with respect to the irradiation incident angle. In addition, two prediction models were proposed and examined to evaluate the absorbed energy distribution rate. Both models reproduce the measurements well. Among them, the prediction model based on view factor in radiative heat transfer is simpler than the other. These models are useful to predict desorption rate of water vapor in a desiccant rotor in which concentrated solar irradiance is used to heat and desorb from the rotor wall.