Numerical analysis of behavior of active layer in rotary kilns by discrete element method
来源期刊:中南大学学报(英文版)2013年第3期
论文作者:XIE Zhi-yin(谢知音) FENG Jun-xiao(冯俊小)
文章页码:634 - 639
Key words:rotary kiln; particle motion; discrete element method; active layer
Abstract: The behavior of the active layer of material bed within rotary kilns plays a key role in industrial applications. To obtain its influences on industrial process, different regimes of particle motion have been simulated by discrete element method (DEM) in three dimensions under variant rotation speeds, filling degree, based on the background of induration process of iron ore pellets. The influences of the mentioned factors on the maximum thickness of the active layer and the average velocity of particles have been investigated. The average velocity of particles increases with Froude number following the power function over a wide range, and the maximum thickness rises with increasing rotation speed in a way of logarithm. The influence of the filling degree f on the maximum thickness exhibits a good linearity under two classic regimes, but the increasing of the average velocity of the active layer is limited at f=0.4. This basic research highlights the impact of the active layer within rotary kilns, and lays a good foundation for the further investigation in mixing and heat transfer within the particle bed inside rotary kilns.
XIE Zhi-yin(谢知音)1, FENG Jun-xiao(冯俊小)2
(1. School of Mechanical Engineering, University of Science and Technology Beijing, Beijing 100083, China;
2. Beijing Key Laboratory for Energy Saving and Emission Reduction of Metallurgical Industry,
Beijing 100083, China)
Abstract:The behavior of the active layer of material bed within rotary kilns plays a key role in industrial applications. To obtain its influences on industrial process, different regimes of particle motion have been simulated by discrete element method (DEM) in three dimensions under variant rotation speeds, filling degree, based on the background of induration process of iron ore pellets. The influences of the mentioned factors on the maximum thickness of the active layer and the average velocity of particles have been investigated. The average velocity of particles increases with Froude number following the power function over a wide range, and the maximum thickness rises with increasing rotation speed in a way of logarithm. The influence of the filling degree f on the maximum thickness exhibits a good linearity under two classic regimes, but the increasing of the average velocity of the active layer is limited at f=0.4. This basic research highlights the impact of the active layer within rotary kilns, and lays a good foundation for the further investigation in mixing and heat transfer within the particle bed inside rotary kilns.
Key words:rotary kiln; particle motion; discrete element method; active layer