title: Phase transition and flow-rate behavior of merging granular flows.
abstract: Merging of granular flows is ubiquitous in industrial, mining, and geological processes. However, its behavior remains poorly understood. This paper studies the phase transition and flow-rate behavior of two granular flows merging into one channel. When the main channel is wider than the side channel, the system shows a remarkable two-sudden-drops phenomenon in the outflow rate when gradually increasing the main inflow. When gradually decreasing the main inflow, the system shows obvious hysteresis phenomenon. We study the flow-rate-drop phenomenon by measuring the area fraction and the mean velocity at the merging point. The phase diagram of the system is also presented to understand the occurrence of the phenomenon. We find that the dilute-to-dense transition occurs when the area fraction of particles at the joint point exceeds a critical value ϕ(c)=0.65±0.03.
authors.affiliation: School of Engineering Science, University of Science and Technology of China, Hefei 230026, P. R. China.
authors.forename: Mao-Bin
authors.initials: MB
authors.lastname: Hu
authors.affiliation: School of Engineering Science, University of Science and Technology of China, Hefei 230026, P. R. China.
authors.forename: Qi-Yi
authors.initials: QY
authors.lastname: Liu
authors.affiliation: School of Engineering Science, University of Science and Technology of China, Hefei 230026, P. R. China.|MOE Key Laboratory for Urban Transportation Complex Systems Theory and Technology, Beijing Jiaotong University, Beijing 100044, P. R. China.
authors.forename: Rui
authors.initials: R
authors.lastname: Jiang
authors.affiliation: Beijing National Laboratory for Condensed Matter Physics and CAS Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Meiying
authors.initials: M
authors.lastname: Hou
authors.affiliation: School of Engineering Science, University of Science and Technology of China, Hefei 230026, P. R. China.
authors.forename: Qing-Song
authors.initials: QS
authors.lastname: Wu