Preprints, Reprints and Papers
"Forces on Bins:
The Effect of Random Friction" (postscript version, with figures).
This paper studies the effect on stresses of a random component of
friction, in models of granular material. First, the classic Janssen
solution for stresses in a bin is reexamined; assumptions about
the size of the random friction translate more-or-less directly into
the size of stress fluctuations. Next, the equilibrium equations
with random friction effects
are solved numerically for a Mohr-Coulomb material. Here,
the size of fluctuations in the coefficient of
wall friction (i.e. a boundary condition)
is seen to be the most significant contribution to
stress fluctuations.
(Phys. Rev. E, vol 57 (1998) p 3170)
"The Mechanics
of Particle-Fluid Flows at high Solids Volume Fraction"
(postscript version, with figures).
This paper presents a model of fluidized beds that incorporates
solids-like stresses, and looks at the stability of slows. It
also introduces a model for computing particle flows in a fluid,
based on solving DEM-like forces and the Navier-Stokes equations.
(IUTAM Speciality Conference on Segregation in Granular
Materials, (2000) A. Rosato and D. Blackmore (eds.), Kluwer.
"Kinematics of
sand avalanches using particle-image velocimetry"
J. Sediment Res. vol 71 (2001) p 355.
"Computing
Granular Avalanches and Landslides"
This paper presents the model equations describing geophysical
mass flows. The basic computational approach is described. (pdf)
This paper appeared in Physics of Fluids.
"Parallel
Adaptive Numerical Simulation of Day Avalanches over Natural Terrain"
A presentation of
our simulation environment to solve the 'thin
layer equations' modelling dry geophysical flows over terrain (pdf).
This paper will appear in J. Volcanology and Geothermal Research.
"A Model of
Granular Flow over an Erodible Surface"
Discrete and Continuous Dynamical Systems: Series B
"Mathematical Modeling, Analysis and Computations"
vol 3, number 4 (2003). This is a
special issue dedicated to David G. Schaeffer's on the occasion of
his 60th birthday.
(pdf)
"A Reduced Model for
Nephron Flow Dynamics Mediated by Tubuloglomerular Feedback"
In: Membrane Transport and Renal Physiology, The IMA Volumes in Mathematics and its Applications, Volume 129, edited by Harold E. Layton and Alan M. Weinstein. New York: Springer-Verlag, pp. 345-364, 2002.
A review of a our basic PDE model of TGF, and a reduced integral model.
(pdf)
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