Research on size segregation dynamics and processes of a binary mixture dense granular flow. (August 2022)

• Record Type: Journal Article
• Authors: Chou, Shih-Hao; Huang, Po-Han; Hsiau, Shu-San
• Is Part Of: Minerals engineering. Volume 186(2022)
• Publication Date: 2022-08
• Subjects: Granular flow -- Segregation -- Rotation speed -- Filling degree; Mines and mineral resources -- Periodicals; Ressources minérales -- Périodiques; Mines and mineral resources; Periodicals; Electronic journals; 622
• DOI: 10.1016/j.mineng.2022.107722
• Languages: English
• ISSNs: 0892-6875

Abstract

Graphical abstract: Center position evolution of particles over time. The red circles and blue squares indicate the big and small particles, respectively. Phase diagram of the binary-size mixture segregation pattern of the ω – f space. BNE, MS, and RBNE were indicated by the circle, diamond, and square, respectively. Highlight: Filling degrees and rotation speed significantly affect particle segregation. Different segregation patterns can be quantified using the segregation index. Granular temperature also crucially influenced the segregation state. Abstract: This study employed an experimental approach to investigate the effects of various filling degrees of the granular bed and the rotation speed on size-induced particle segregation behavior in an almost fully filled double-walled rotating drum. The distributions of the concentrations of bicolor particles in the system were obtained via image processing to determine the segregation state. The dynamics of the mixture flow including the statistical distribution, the azimuthal angle and radial direction granular temperature profiles were measured and calculated via particle-tracking velocimetry (PTV). The results were similar for the Brazil-nut effect and its reverse in the radial direction at high or low rotation speeds. When the rotation speed or filling degree was changed, the effect on two different particle sizes in the binary mixture system was inconsistent, and different flow mechanisms led to different segregation patterns. Two phase diagrams with the rotation speed and filling degree and the magnitude and position of the maximum granular temperature as the space enabled the prediction of segregation states.