Effects of material properties on the competition mechanism of heat transfer of a granular bed in rotary cylinders  

作　　者：谢知音 冯俊小 

机构地区：[1]School of Mechanical Engineering, University of Science and Technology Beijing

出　　处：《Chinese Physics B》2013年第8期489-495,共7页中国物理B（英文版）

基　　金：supported by the National High Technology Research and Development Program of China(Grant No.2007AA05Z215);the Fundamental Research Funds for the Central Universities(Grant No.FRF-AS-10-005B)

摘　　要：Mixing and heat transfer processes of the granular materials within rotary cylinders play a key role in industrial processes. The numerical simulation is carried out by using the discrete element method （DEM） to investigate the influences of material properties on the bed mixing and heat transfer process, including heat conductivity, heat capacity, and shear modulus. Moreover, a new Prclet number is derived to determine the dominant mechanism of the heating rate within the particle bed, which is directly related to thermal and mechanical properties. The system exhibits a faster heating rate with the increase of ratio of thermal conductivity and heat capacity, or the decrease of shear modulus when inter-particle conduction dominates the heating rate; conversely, it shows a fast-mixing bed when particle convection governs the heating rate. The simulation results show good agreement with the theoretical predictions.Mixing and heat transfer processes of the granular materials within rotary cylinders play a key role in industrial processes. The numerical simulation is carried out by using the discrete element method （DEM） to investigate the influences of material properties on the bed mixing and heat transfer process, including heat conductivity, heat capacity, and shear modulus. Moreover, a new Prclet number is derived to determine the dominant mechanism of the heating rate within the particle bed, which is directly related to thermal and mechanical properties. The system exhibits a faster heating rate with the increase of ratio of thermal conductivity and heat capacity, or the decrease of shear modulus when inter-particle conduction dominates the heating rate; conversely, it shows a fast-mixing bed when particle convection governs the heating rate. The simulation results show good agreement with the theoretical predictions.

关 键 词：rotary cylinder particle mixing heat conduction material properties 

分 类 号：TK124[动力工程及工程热物理—工程热物理]