Factors influencing feed distribution uniformity in aquaculture vessels based on DEM

Abstract

To meet the feeding operation requirements of aquaculture vessels and enhance feed quality while minimizing fish competition and uneven feeding—factors that can degrade feed quality—a low-speed, uniformly distributing feeding disk was designed. This study uses Star-CCM+ to simulate the feed dispersal process of the rotating feeding disk and analyzes the effects of various factors on feed particle distribution. A discrete element model based on the mesh-free method was developed, incorporating the Hertz-Mindlin contact model for discrete feed particles, with rotating speed, height above the water surface, and initial particle velocity as variables. The shape and range of the dispersed feed distribution were observed. The results indicate that appropriately increasing the rotating speed or height improves feed distribution uniformity and increases the dispersal range. The optimal feeding effect is achieved when the drop height is 2 m and the rotating speed is 20 rpm. To evaluate the impact of ship roll on feed distribution, initial particle velocities were set to simulate changes under unstable sea conditions. When the initial particle velocity is 0.75 m/s, increasing the rotating speed to 20 rpm enhances distribution uniformity. This study provides valuable insights into the design and operational parameters of rotating feeding disks and serves as a reference for the development of feeding equipment for aquaculture vessels.