Effects of particle size distribution on drying characteristics in a drum by XDEM: A case study

The objective of this study is analysis of drying process of wet woody particles in a circulating cylinder including dynamics investigation of moving particles by eXtended Discrete Element Method (XDEM). In this approach, the particles are resolved as discrete phase coupled via heat, mass and momentum transfer to the surrounding gas phase. The drying of a spherical single particle is validated with experiments for different particle diameter and the temperature behavior during drying is investigated in addition to the moisture content and drying rate of the particle so that the comparisons show a good agreement meaning XDEM is a reliable tool to simulate drying process. The test case is a cylinder rotating with a constant angular velocity including a bed of moist wood particles. The main focus of this work is evaluating the effect of particle size distribution on drying rate and heat loss in the system. Furthermore, the influence of the inlet gas temperature and velocity on the particle bed mean temperature and moisture content is investigated. Eventually, the surface temperature distribution of particles in different instances during drying is visually demonstrated and the behavior of surface area on residence time is discussed. (C) 2016 Elsevier Ltd. All rights reserved.