Mathematical Modeling of a Thin Layer Solar Kiln

Abstract

Mathematical modeling of a thin layer solar kiln for drying of agricultural products is presented. Governing equations of the air temperature and air humidity ratio, material temperature and its moisture content, and the glass temperature are derived together with their initial conditions. Heat and mass transfer between the material and the air and the air and the glass cover are estimated using empirical relations for the coefficients of heat and mass transfer. The results of the calculations are analyzed to predict the effect of the following parameters on the transient performance of the kiln: (a) rate of absorbed solar energy in the kiln, (b) rate of air flow through the kiln, (c) volume of the dried material, (d) ambient temperature, and (e) humidity ratio of the ambient air.