dc.contributor.author Collinson, Roger dc.contributor.supervisor Dr Peg-Foo Siew dc.contributor.supervisor Dr Yong-Hong Wu dc.date.accessioned 2017-01-30T10:15:20Z dc.date.available 2017-01-30T10:15:20Z dc.date.created 2008-05-14T04:36:22Z dc.date.issued 1998 dc.identifier.uri http://hdl.handle.net/20.500.11937/1930 dc.description.abstract A mathematical study has been undertaken to model various kinds of granular flows including the perfect plasticity flow and the viscous elasto-plasticity flow. The work is mainly based on the double-shearing theory originated by Spencer and developed by many others. The focus of the project is on the formulation of the theory, the construction of mathematical models and the development of robust simulation techniques.Based on a general formulation of the double-shearing theory, the perfect plasticity flow is shown to be governed by a set of highly nonlinear first order hyperbolic partial differential equations with two distinct characteristics. A sophisticated numerical algorithm is then developed based on the method of characteristics to determine the stress discontinuity and the velocity and stress fields. With the method developed, a numerical study is then undertaken to model the flow of granular materials in a hopper in the presence of stress discontinuity and to investigate the influence of various parameters on the distribution of hopper wall pressures.Utilising the double shearing theory, a set of stress-strain constitutive equations in explicit form has been derived, which makes it possible to formulate the double-shearing theory within the framework of the finite element method. Thus, consequently, a sophisticated finite element technique has been developed to solve the general boundary value problem governing the viscous elasto-plasticity flows obeying the double-shearing theory. Numerical implementation of the frictional boundary condition is also presented. The model is then illustrated with a numerical example demonstrating the influence of wall friction on the distribution of pressures on silo walls throughout the dynamic process of material discharge from silos. dc.language en dc.publisher Curtin University dc.subject mathematical models dc.subject numerical techniques dc.subject granular flows dc.title Mathematical models and numerical techniques for plasticity flows of granular media. dc.type Thesis dcterms.educationLevel PhD curtin.thesisType Traditional thesis curtin.department School of Mathematics and Statistics curtin.identifier.adtid adt-WCU20020701.164913 curtin.accessStatus Open access
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