A preliminary study on energy dissipating mechanism for viscous debris flow
The energy, dissipated by a two-phase (solid and liquid) viscous debris flowunder steady and uniform flow conditions, can be approximately expressed by a hydraulic energy gradient J to be composed of Jl for the liquid phase and Js for the solid phase. Expressions of the hydraulic energy gradient for each phase have been derived from Darcys resistance formula assuming laminar flow. The summation of Jl and Js provides a minimum value Jmin under the same hydraulic radius R, and corresponds to a critical diameter d0 between the coarse particle of the solid phase and the fine particle of the liquid phase. By analyzing field data measured at Jiangjia gully, Yunnan Province, China, a relationship between the minimum energy gradient Jmin and the critical diameter d0 for a viscous debris flow has been established, in which the minimum energy gradient decreases with increasing critical diameter and hydraulic radius. Based on this, the mechanism by which energy dissipation in the viscous debris flowadjusts is revealed. These results are very significant for developing a newdynamical model for viscous debris flow and for predicting disasters due to debris flows.
viscous debris flow energy dissipation hydraulic energy gradient critical diameter
A.P. Shu X.J. Fei Y. Feng
College of Water Sciences, Key Laboratory of Water and Sediment Sciences of MOE, Beijing Normal Univ The State Key Laboratory of Hydrosciences and Engineering, Tsinghua University, Beijing, China School of Geography and Remote Sensing Sciences, Beijing Normal University, Beijing, China
国际会议
成都
英文
131-137
2007-05-17（万方平台首次上网日期，不代表论文的发表时间）