Generation Mechanism of Convection in Vertically Vibrating Powder Beds

JOURNAL OF CHEMICAL ENGINEERING OF JAPAN

Yuichi Yoshida¹  Yoshiyuki Shirakawa¹  Jusuke Hidaka¹  Atsuko Shimosaka¹  Ken-ichi Hamada¹ 

[1] Department of Chemical Engineering and Materials Science, Faculty of Science and Engineering, Doshisha University

关键词: Convection Roll;    Particle Beds;    Slip Lines;    DEM Simulation;    Granular Mechanics;   

DOI  :  10.1252/jcej.12we145

来源: Maruzen Company Ltd

【 摘 要 】

References(17)A mechanism is proposed to explain the generation of convection in vibrating powder beds based on powder mechanics. Convection induced in the vibrating powder beds was observed and the influences of the vibration amplitude and frequency on the convection were investigated experimentally. The flow behavior of the vibrating powder beds was simulated using the discrete element method (DEM) to obtain the state variables of convection, such as bulk density and velocity. A mechanical model of convection is proposed based on the microscopic observation of the flow behavior of particles and formation of convection cells in the bed by DEM simulation. Triangular and V-shaped compressed particle zones of particles were formed in alternating fashion in the vibrating powder bed, and the generation of these compressed zones repeated every two vibration cycles leads to particle convection in the bed. The number of convective rolls in the vibrating powder bed increases with an increase in the centrifugal effect. The number of isosceles-triangle-shaped compressed zones formed at the bottom of the container increased with an increase in the centrifugal effect, leading to an increase in the number of convective rolls in the vibrating powder bed.

【 授权许可】

Unknown