Preliminary Study on the Mechanisms of Solids Segregation in Debris Flows

作     者：Zhou Gong-Dan 1, 2 Sun Qi-Cheng 3 1 Key Laboratory of Mountain Hazards and Earth Surface Processes, Chinese Academy of Sciences, Chengdu,610059 China 2 Institute of Mountain Hazards and Environment, Chinese Academy of Sciences and Ministry of Water Conservancy, Chengdu,610059 China 3 State Key Laboratory for Hydroscience and Engineering, Tsinghua University, Beijing, 100083 China 

会议名称：《2012颗粒材料计算力学会议》

会议日期：2012年

学科分类：080704[工学-流体机械及工程] 08[工学] 0807[工学-动力工程及工程热物理] 0837[工学-安全科学与工程] 

基　　金：support from the Sichuan Youth Science and Technology Foundation (Grant No.2012JQ0043) the Hundred Young Talents Program of the Institute of Mountain Hazards and Environment 

关 键 词：Debris flow reverse segregation Discrete Element Method 

摘      要：Studies of the mechanisms and the effects on the flowing mobility for hazardous geophysical flows (e.g., debris flows) is crucial for hazard mitigation and prediction. Granular flows with grains of mixed sizes are numerically modeled and the contact behavior of solid particles is fundamentally studied using the Discrete Element Method (DEM). Compared to granular flows with uniform solid particles, the effect of segregation on granular flowing mobility is investigated. It is found that reverse segregation can significantly influence the flowing mobility and the flowing regimes in the front head of the granular body. The development of solids segregation needs certain traveling distances, which depend on the slope inclination. This research illustrates that the segregation for debris flows is usually completed before the flows become inertial flows.