109 citations · 328 across the 16 of their papers we have counts for
17 papers
A Primer on the Dynamical Systems Approach to Transport in Porous Media
Guy Metcalfe, Daniel Lester, Michael Trefry
Historically, the dominant conceptual paradigm of porous media flow, solute mixing and transport was based on steady two-dimensional flows in heterogeneous porous media. Although i…
Scalar signatures of chaotic mixing in porous media
Heyman J., Lester D., Le Borgne T
Steady laminar flows through porous media spontaneously generate Lagrangian chaos at pore scale, with qualitative implications for a range of transport, reactive and biological pro…
Lagrangian complexity persists with multimodal flow forcing in poroelastic systems
Michael Trefry, Daniel Lester, Guy Metcalfe +1
We extend previous analyses of the origins of complex transport dynamics in poroelastic media to the case where the input transient signal at a boundary is generated by a multimoda…
Hierarchical Jamming in Frictional Particle Assemblies
Ruru Li, Daniel Lester
The postulate of the existence of a jamming phase diagram (Liu and Nagel, Nature 396, 21 EP (1998aa)) provides a theoretical basis for the classification of a wide range of amorpho…
Global Organization of Three-Dimensional, Volume-Preserving Flows: Constraints, Degenerate Points, and Lagrangian Structure
Bharath Ravu, Guy Metcalfe, Murray Rudman +2
Global organization of 3-dimensional (3D) Lagrangian chaotic transport is difficult to infer without extensive computation. For 3D time-periodic flows with one invariant we show ho…
Natural Groundwater Systems Can Display Chaotic Mixing at the Darcy Scale
Michael Trefry, Daniel Lester, Guy Metcalfe +1
Although steady, isotropic Darcy flows are inherently laminar and non-mixing, it is well understood that transient forcing via engineered pumping schemes can induce rapid, chaotic…
Continuous Time Random Walks for the Evolution of Lagrangian Velocities
Marco Dentz, Peter K. Kang, Alessandro Comolli +2
We develop a continuous time random walk (CTRW) approach for the evolution of Lagrangian velocities in steady heterogeneous flows based on a stochastic relaxation process for the s…
Localized shear generates three-dimensional transport
Lachlan D. Smith, Murray Rudman, Daniel R. Lester +1
Understanding the mechanisms that control three-dimensional (3D) fluid transport is central to many processes including mixing, chemical reaction and biological activity. Here a no…
The Lagrangian Deformation Structure of Three-Dimensional Steady Flow
Daniel R. Lester, Marco Dentz, Tanguy Le Borgne +1
Fluid deformation and strain history are central to wide range of fluid mechanical phenomena ranging from fluid mixing and particle transport to stress development in complex fluid…
Chaotic Mixing in Three Dimensional Porous Media
Daniel R. Lester, Marco Dentz, Tanguy Le Borgne
Under steady flow conditions, the topological complexity inherent to all random 3D porous media imparts complicated flow and transport dynamics. It has been established that this c…
Hydrodynamic drift ratchet scalability
James Herringer, Daniel Lester, Graham E. Dorrington +2
The rectilinear "drift" of particles in a hydrodynamic drift ratchet arises from a combination of diffusive motion and particle-wall hydrodynamic interactions, and is therefore dep…
Fluid Stretching as a Levy Process
Marco Dentz, Daniel R. Lester, Tanguy Le Borgne +1
We study the relation between flow structure and fluid deformation in steady two-dimensional random flows. Beyond the linear (shear flow) and exponential (chaotic flow) elongation…
Dynamic and rate-dependent yielding in model cohesive suspensions
Richard Buscall, Peter J. Scales, Anthony D. Stickland +3
An experimental system has been found recently, a coagulated CaCO3 suspension system, which shows very variable yield behaviour depending upon how it is tested and, specifically, a…
Correction of Wall Adhesion Effects in Batch Settling of Strong Colloidal Gels
Daniel R. Lester, Richard Buscall
The batch settling test is widely used to estimate the compressive rheology of strongly flocculated colloidal suspensions, in particular the compressive yield strength and hydrauli…
The yielding of concentrated cohesive suspensions can be deformation rate dependent
Richard Buscall, Peter J. Scales, Anthony D. Stickland +4
The yielding of concentrated cohesive suspensions can be deformation-rate dependent. One consquence of this is that a single suspension can present in one several different ways, d…
Correction of Wall Adhesion Effects in the Centrifugal Compression of Strong Colloidal Gels
Richard Buscall, Daniel R. Lester
Several methods for measuring the compressive strength of strong particulate gels are available, including the centrifuge method, whereby the strength as a function of volume-fract…
Wall Adhesion and Constitutive Modelling of Strong Colloidal Gels
Daniel R. Lester, Richard Buscall, Anthony D. Stickland +1
Wall adhesion effects during batch sedimentation of strongly flocculated colloidal gels are commonly assumed to be negligible. In this study in-situ measurements of colloidal gel r…