Simulation and Analysis of Potato Drying in an Indirect Solar Dryer: Influence of RT25 Phase Change Material Under Addis Ababa and Algiers Conditions

Abstract

The present paper proposes a numerical simulation model for predicting the effect of RT 25 phase change material slabs on the natural convention solar drying of potato slices. The model was developed and validated using the environmental condition of Addis Ababa (Ethiopia). Model projections were also made under the environmental conditions of Algiers in the Maghreb region. Thermophysical parameters of potato slice were taken from the literature during model development. The study considered an airflow entering the solar collector at 35 °C with PCM initial temperature at 25 °C. Results show that the PCM at the inlet of the collector rapidly absorbs energy, leading to a significant reduction of the outlet air temperature to 25 °C during the initial period (0.25h). However, as the drying progresses, the PCM approaches thermal equilibrium, and the outlet air temperature rises to 31.5 °C after 2 h. The validated model without PCM closely predicted the experimental data, with a relative error ranging from 4–9% and coefficients of determination of 89– 98%. The influence of PCM slab length and initial temperature on the drying kinetic of the potato slices was further analysed. Phase Change Material slab length showed minimal influence on drying kinetics, suggesting future work should focus on hygroscopic products with longer drying times.