Browsing Τμήμα Μαθηματικών και Στατιστικής / Department of Mathematics and Statistics by Subject "Yield stress"
Now showing items 1-17 of 17
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Cessation of annular Poiseuille flows of Bingham plastics
(2007)We numerically solve the cessation of the annular Poiseuille flow of Bingham plastics for various values of the diameter ratio, using the regularized constitutive equation proposed by Papanastasiou and employing finite ...
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Article
Cessation of Couette and Poiseuille flows of a Bingham plastic and finite stopping times
(2005)We solve the one-dimensional cessation Couette and Poiseuille flows of a Bingham plastic using the regularized constitutive equation proposed by Papanastasiou and employing finite elements in space and a fully implicit ...
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Article
Cessation of Newtonian circular and plane Couette flows with wall slip and non-zero slip yield stress
(2017)We solve analytically the cessation flows of a Newtonian fluid in circular and plane Couette geometries assuming that wall slip occurs provided that the wall shear stress exceeds a critical threshold, the slip yield stress. ...
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Article
Cessation of viscoplastic Poiseuille flow in a square duct with wall slip
(2015)We solve numerically the cessation of the pressure-driven Poiseuille flow of a Bingham plastic under the assumption that slip occurs along the wall following a generalized Navier-slip law involving a non-zero slip yield ...
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Article
Cessation of viscoplastic Poiseuille flow with wall slip
(2014)We solve numerically the cessation of axisymmetric Poiseuille flow of a Herschel-Bulkley fluid under the assumption that slip occurs along the wall. The Papanastasiou regularization of the constitutive equation is employed. ...
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Article
Combined effects of compressibility and slip in flows of a Herschel-Bulkley fluid
(2013)In this work, the combined effects of compressibility and slip in Poiseuille flows of Herschel-Bulkley fluids are investigated. The density is assumed to obey a linear equation of state, and wall slip is assumed to follow ...
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Article
Determination of the rheological parameters of self-compacting concrete matrix using slump flow test
(2010)The classification of a concrete mixture as self-compacting (SCC) is performed by a series of empirical characterization tests that have been designed to assess not only the flowability of the mixture but also its segregation ...
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Newtonian flow in a triangular duct with slip at the wall
(2013)We consider the Newtonian Poiseuille flow in a tube whose cross-section is an equilateral triangle. It is assumed that boundary slip occurs only above a critical value of the wall shear stress, namely the slip yield stress. ...
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Article
Newtonian Poiseuille flows with slip and non-zero slip yield stress
(2013)The Newtonian Poiseuille flow is considered for various geometries, under the assumption that wall slip occurs above a critical value of the wall shear stress known as, the slip yield stress. In the axisymmetric and planar ...
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Numerical study of the combined effects of inertia, slip, and compressibility in extrusion of yield stress fluids
(2014)The axisymmetric extrudate swell flow of a compressible Herschel–Bulkley fluid with wall slip is solved numerically. The Papanastasiou-regularized version of the constitutive equation is employed, together with a linear ...
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On the early breakdown of semisolid suspensions
(2007)Semisolid materials are suspensions of metal alloys which are processed while in a mushy state. In this state, the suspensions behave as viscoplastic materials with time-dependent material properties. During processing, ...
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Predictions of structure breakdown, buildup and shear banding in semisolid suspensions
(2008)When SSM material is subjected to a sudden transient the rate of buildup (aging) is negligible compared to the rate of breakdown (shear rejuvenation). While this is generally true, due to prolonged processing or the geometry ...
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Article
Shear rejuvenation, aging and shear banding in yield stress fluids
(2009)The purpose of this work is to simulate shear rejuvenation and aging effects in shear thinning yield stress fluids in a typical rotational rheometer and to provide a common framework to describe the behavior of yield stress ...
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Article
Squeeze flow of thixotropic semisolid slurries
(2014)An essential element for the integration of a semisolid process in the production of complex commercial components is the availability of accurate mathematical and computational tools that could describe both the rheological ...
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Article
Thixotropic flow past a cylinder
(2014)We study the flow of a thixotropic fluid around a cylinder. The rheology of the fluid is described by means of a structural viscoplastic model based on the Bingham constitutive equation, regularised using the Papanastasiou ...
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Viscoplastic flow development in tubes and channels with wall slip
(2016)The development of Bingham plastic flow in tubes and channels is investigated numerically using the Papanastasiou regularization and finite element simulations. It is assumed that slip occurs along the wall following ...
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Article
Viscoplastic Poiseuille flow in a rectangular duct with wall slip
(2014)We solve numerically the Poiseuille flow of a Herschel-Bulkley fluid in a duct of rectangular cross section under the assumption that slip occurs along the wall following a slip law involving a non-zero slip yield stress. ...