Conjugate CFD modeling for Multi-Sample drying of deformable porous food materials

Drying of deformable porous materials (DPMs) involves complex coupling of heat transfer, moisture migration, and structural deformation, which are often oversimplified in conventional models. This study introduces a novel CFD-integrated conjugate model for hot air drying of multiple deformable food samples, capturing real-time changes in air properties and sample interactions. A key innovation lies in the investigation of drying kinetics and temperature distribution under two deformation approaches: (i) uniform deformation using a constant shrinkage velocity, and (ii) non-uniform deformation based on transport properties and the glass transition concept. The model reveals that deformation significantly alters drying kinetics by increasing surface area-to-volume ratio (SAVR), reducing internal resistance, and enhancing heat transfer from surface to center. These effects accelerate moisture migration and improve drying efficiency. Additionally, variations in drying conditions such as air velocity, temperature, and sample arrangement further influence the heat and mass transfer dynamics, leading to spatial disparities in drying rates. Upstream samples dry faster due to higher exposure to hot air, while downstream samples experience delayed moisture loss. The study reveals that deformation patterns and air distribution significantly influence temperature, moisture, and velocity profiles in multi-layer drying. These insights contribute to the development of more uniform and energy-efficient drying strategies for porous food materials.