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Title: The frictional flow of a dense granular material based on the dilatant double shearing model

Abstract

Slow flow of granular materials, which typically occurs during the emptying of industrial storage hoppers and bins, has great industrial relevance. In the present study, we have employed our newly developed dilatant double shearing model [H. Zhu, M.M. Mehrabadi, M. Massoudi, Incorporating the effects of fabric in the dilatant double shearing model for granular materials, Int. J. Plast. 22 (2006) 628-653] to study the slow flow of a frictional, dense granular material. Although most models pertain only to the fully developed granular flow, the application of the dilatant double shearing model is shown to be valid from the onset of granular flow to the fully developed granular flow. In this paper, we use the finite element program ABAQUS/Explicit to numerically simulate the granular Couette flow and the frictional granular flow in a silo. For the granular Couette flow, the relative density variation and the velocity profile obtained by using the dilatant double shearing model are in good quantitative agreement with those obtained from a DEM simulation. For the frictional flow in a silo, the major principal stress directions are obtained at various time steps after the onset of silo discharge. We find that, in the hopper zone, the arching ofmore » the granular material between the sloping hopper walls is clearly demonstrated by the change in direction of the major principal stress. We also compare the pressure distribution along the wall before and after the onset of silo discharge. The numerical results show that the dilatant double shearing model is capable of capturing the essential features of the frictional granular flow.« less

Authors:
 [1]; ;  [1]
  1. (Tulane University, New Orleans, LA)
Publication Date:
Research Org.:
National Energy Technology Laboratory (NETL), Pittsburgh, PA, and Morgantown, WV; Tulane University, New Orleans, LA
Sponsoring Org.:
USDOE - Office of Fossil Energy (FE)
OSTI Identifier:
912833
Report Number(s):
DOE/NETL-IR-2007-062
Journal ID: ISSN 0898-1221; TRN: US200802%%401
DOE Contract Number:
None cited
Resource Type:
Journal Article
Resource Relation:
Journal Name: Computers and Mathematics with Applications; Journal Volume: 53; Journal Issue: 2
Country of Publication:
United States
Language:
English
Subject:
99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE; COUETTE FLOW; DISTRIBUTION; GRANULAR MATERIALS; HOPPERS; SIMULATION; STORAGE; VELOCITY; granular materials; dilatant double shearing model; constitutive relations, couette flow, DEM, silo flow

Citation Formats

Zhu, H., Mehrabadi, M.M., and Massoudi, M.C.. The frictional flow of a dense granular material based on the dilatant double shearing model. United States: N. p., 2007. Web. doi:10.1016/j.camwa.2006.02.054.
Zhu, H., Mehrabadi, M.M., & Massoudi, M.C.. The frictional flow of a dense granular material based on the dilatant double shearing model. United States. doi:10.1016/j.camwa.2006.02.054.
Zhu, H., Mehrabadi, M.M., and Massoudi, M.C.. Mon . "The frictional flow of a dense granular material based on the dilatant double shearing model". United States. doi:10.1016/j.camwa.2006.02.054.
@article{osti_912833,
title = {The frictional flow of a dense granular material based on the dilatant double shearing model},
author = {Zhu, H. and Mehrabadi, M.M. and Massoudi, M.C.},
abstractNote = {Slow flow of granular materials, which typically occurs during the emptying of industrial storage hoppers and bins, has great industrial relevance. In the present study, we have employed our newly developed dilatant double shearing model [H. Zhu, M.M. Mehrabadi, M. Massoudi, Incorporating the effects of fabric in the dilatant double shearing model for granular materials, Int. J. Plast. 22 (2006) 628-653] to study the slow flow of a frictional, dense granular material. Although most models pertain only to the fully developed granular flow, the application of the dilatant double shearing model is shown to be valid from the onset of granular flow to the fully developed granular flow. In this paper, we use the finite element program ABAQUS/Explicit to numerically simulate the granular Couette flow and the frictional granular flow in a silo. For the granular Couette flow, the relative density variation and the velocity profile obtained by using the dilatant double shearing model are in good quantitative agreement with those obtained from a DEM simulation. For the frictional flow in a silo, the major principal stress directions are obtained at various time steps after the onset of silo discharge. We find that, in the hopper zone, the arching of the granular material between the sloping hopper walls is clearly demonstrated by the change in direction of the major principal stress. We also compare the pressure distribution along the wall before and after the onset of silo discharge. The numerical results show that the dilatant double shearing model is capable of capturing the essential features of the frictional granular flow.},
doi = {10.1016/j.camwa.2006.02.054},
journal = {Computers and Mathematics with Applications},
number = 2,
volume = 53,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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