Characterization of the powder flow behavior of cooked Adzuki bean using image analysis and grinding models

The study employed thin-layer models and sigmoid model to analyze the drying behavior and grinding kinetics of the Adzuki bean (AB) powder, respectively. Particle size distributions were determined using conventional sieving and a vibrator with image analysis, providing accurate measurements within a narrower size range (0.1 mm–3.0 mm) in the sample. The flow properties were evaluated across different particle sizes ranging from 0.25 mm to 2.00 mm. These flow characteristics were then utilized for designing a hopper. The study revealed that the smallest particle size (0.25 mm) exhibited the lowest flowability (1.7873 and 1.4384 for 10% and 15% moisture content (MC), respectively). Additionally, the internal friction angle varied significantly for particle sizes between 0.60 and 1.70 mm at 10% MC, while at 15% MC, a greater effect of friction due to moisture was observed. Furthermore, the study highlighted the need for a larger hopper angle and opening for the smallest particle sizes.