Recognition of the granular airborne portion in a flighted rotary drum

This article deals with numerical simulation via Discrete Element Method (DEM) in a flighted rotary drum with a varying number of flights from 1 to 25 at a constant load of particles. The granular behavior kinematics is studied in the three regimes: under-, design-and over-loading. It was shown that the behavior of granular material during the unloading process from the flights governs the regime transitions. The cross-sectional distribution analysis of the granular material in the different parts of the drum established the existence of two dense media (bed and flights) and one dilute medium (in the airborne portion). Since one of the criteria that affect the ef-ficiency of heat transport between the gas and the particle media is the number of particles in the airborne phase, three recognition methods are proposed to detect the airborne portion. Based on geometry, velocity magnitude, and minimal separation distance, the comparison between them provides a basis for discussion about the rele-vance of each method in detecting these airborne particles.

Automated summary

This article focuses on the numerical simulation of a flighted rotary drum using Discrete Element Method (DEM), with varying number of flights (1 to 25) and a constant load of particles. The study investigates the kinematics of granular behavior in three loading conditions: under-, design-, and over-loading. The results demonstrate that the behavior of granular material during unloading from the flights determines the transitions between different regimes. The analysis of granular material distribution in different parts of the drum reveals the presence of two dense media (bed and flights) and one dilute medium (in the airborne portion). Considering the importance of the number of particles in the airborne phase for heat transport efficiency between gas and particle media, three recognition methods are proposed to detect the airborne particles and their relevance is discussed based on geometry, velocity magnitude, and minimal separation distance.