CFD Analysis of an Indirect Solar Dryer Operating under Natural Conditions in Meknes, Morocco

This study focuses on the design, development, and analysis of an indirect solar food drying system tailored to the climatic conditions of Meknes, Morocco. The system aims to effectively reduce the moisture content of various products and consists of two main components: a solar air collector (SAC) and a drying cabinet. Computational Fluid Dynamics (CFD) was used to analyze airflow distribution and thermal characteristics within the dryer. Temperature measurements taken in July showed peak temperatures of 64.8 and 57.6°C at the SAC outlet, and 57.4 and 51.4°C at the drying chamber outlet on the first and second days, respectively. The comparison between numerical and experimental data yielded a maximum percentage difference of 1.25%. The temperature contours revealed higher temperatures at the chamber inlet, particularly near the floor. The average outlet temperature and air velocity were 43.8°C and 1.48 m/s, respectively, with a consistent temperature profile as air passed through the trays. The pressure distribution within the chamber was uniform. Temperature values at the dryer outlet increase by decreasing air flow rate, with 51.8°C recorded at the lowest mass flow rate of 0.0109 kg/s. Finally, the drying kinetics of banana slices were best described by the Page model, with an effective moisture diffusivity of 3.06 × 10–10 m2/s.