CFD simulation and experimental analysis of flow dynamics and grinding performance of opposed fluidized bed air jet mill

This paper presents a three dimensional Computational Fluid Dynamics (CFD) model to investigate the flow dynamics of solid–gas phases during fine grinding in an air jet mill. Alpine 100AFG fluidized bed air jet mill is considered for the study and the jet milling model is simulated using FLUENT 6.3.2 using a standard k-ε model. The model is developed in GAMBIT 2.3.16 and meshed by tet/hybrid (T-Grid) and Triangular (Pave) meshes. The effects of operating parameters such as solid feed rate, grinding air pressure and internal classifier speed on the performance of the jet mill are analyzed. The CFD simulation results are presented in the forms of dual phase vector plot, volume fraction of phases and particle trajectories during fine grinding process. The mass of ground feed entering and leaving the cyclone (underflow) is also computed by simulation. The proposed model gives realistic predictions of the flow dynamics within the jet mill. Experiments are conducted on the Alpine 100AFG jet mill to study the particle size, morphology and mass of the ground product. The numerical results are found in good agreement with the experimental results.     

在特殊疫情背景下《城市地理资讯学》MOOC课程教学实施效果分析

在新冠肺炎疫情期间,线上教学大规模开展,相关线上教学问题逐渐成为研究热点.传统的测绘地理类课程的教学方式主要是上课时以老师传授知识为主,课后以学生完成作业为辅的方式进行.但是,这种教学方式比较单一,并且在科学化考核和促进学生学习主动性等方面存在诸多问题.然而,线上网络课程是通过互联网以电子设备为教学平台,具有不受教学时...     

一个中国边缘海的风-浪-流预报系统

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