Modelling of Indirect Solar Drying with and without a Thermal Storage Unit for Tomatoes

Abstract

The present work presents indirect solar drying with or without a tomato drying unit and the mathematical modelling of the indirect solar drying system with or without a storage unit. Heat and mass transfer equations were used to predict the thermal behaviour of solar drying with or without a tomato unit. During the experiment, the tomatoes were dried to an average final moisture content of 0.12 kg water /kg ms with an average initial water content of 17.6 kg water /kg ms . The experimental data were fitted to eight (08) different mathematical thin film drying models. These models were compared using the coefficient of determination R 2 , Ki-square χ 2 and the square root of the root mean square error RMSE. The results show that Page’s model best describes the drying curve characteristic of tomatoes. This Page’s model gives a higher value of determination R 2 = 0.9942 and lower values of Ki-square χ 2 = 0.02797 and RMSE = 0.00704, compared with the seven (07) other mathematical methods used to describe the thermal behavior of tomato solar drying.