Discrete and continuum modeling of granular flow in silo discharge

• Published in: Particuology 2018-02, Vol.36 (1), p.127-138
• Main Authors: Tian, Tian, Su, Jinglin, Zhan, Jinhui, Geng, Shujun, Xu, Guangwen, Liu, Xiaoxing
• Format: Article
• Language: English
• Subjects: Discharge rate; Discrete-element model; Flow pattern; Frictional viscosity model; Silo; 流动模式; 分泌物; 连续统; 地窖; 分离; 模特儿; 粘性模型; type-B
• ISSN: 1674-2001; 2210-4291
• DOI: 10.1016/j.partic.2017.04.001

Granular material discharge from a flat-bottomed silo has been simulated by using continuum modeling and a three-dimensional discrete-element method （DEM）. The predictive abilities of three commonly used frictional viscosity models （Schaeffer, S-S, and μ（I）） were evaluated by comparing them with the DEM data. The funnel-flow pattern （type C） and the semi-mass-flow pattern （type B） that was predicted by DEM simulations can be represented when the Schaeffer orμ（I） model is used, whereas the S-S model gives a consistent type-B flow pattern. All three models over-estimate the discharge rate compared with the DEM. The profiles of the solids volume fraction and the vertical velocity above the outlet show that the larger discharge rates given by the Schaeffer and μ（I） model result from an over-estimation of volume fraction, whereas the deviation in the S-S model stems from the failure to predict a solid vertical velocity and a volume fraction.