A novel multi-tray cabinet dryer for thin-layer foods: design and CFD-based optimization to enhance drying uniformity

Uniform drying is essential for ensuring product quality and process efficiency in food dehydration. This study presents a CFD-based design and optimization of a multi-tray cabinet dryer for thin-layer food drying under fully loaded conditions. A 32-tray dryer with a capacity of 42 kg was modeled, and three-dimensional airflow and heat transfer were analyzed using Computational Fluid Dynamics (CFD) integrated with Response Surface Methodology (RSM) and Analysis of Variance (ANOVA). Key geometric parameters including supply zone gap, baffle configuration and angle, and supply fan placement were systematically optimized to enhance airflow and temperature distribution uniformity throughout the drying chamber. The optimized design significantly improved airflow uniformity across all trays, enabling consistent convective heat transfer and uniform moisture removal. Comparative evaluation of two outlet configurations a conventional exhaust fan and a novel revolved outlet demonstrated that the revolved outlet provides more balanced airflow distribution and superior drying uniformity. Overall, the proposed dryer configuration offers a scalable and practical solution for uniform thin-layer food drying, providing clear design guidance for improving the performance of industrial multi-tray drying systems.