DISCRETE ELEMENT SIMULATION OF APPLE VIBRATION DAMAGE

Abstract

Making use of the Discrete Element Method (DEM) a study is presented of the influence of mechanical parameters (vibration frequency and acceleration amplitude, apple size, stacking height) on vibration damage of apples (Malus × domestica) during bulk transport. As acceleration input a sinus in the vertical direction was applied. Realistic parameters of the Kuwabara and Kono (1987) contact force model for apples and bruise prediction models have been applied. Major influences of mechanical parameters on the vibration damage were identified, in particular stacking height and fruit size. A study was performed to investigate the relation between apple positions in the stacking and bruise damage. The existence of damage chains within the core of the apple stacking was also identified, that is in accordance with the well-known force chains in bulk materials.