61 citations · 205 across the 13 of their papers we have counts for
13 papers
Dilation-invariant bending of elastic plates, and broken symmetry in shells
E. Vitral, J. A. Hanna
We propose bending energies for isotropic elastic plates and shells. For a plate, we define and employ a surface tensor that symmetrically couples stretch and curvature such that a…
Selective energy and enstrophy modification of two-dimensional decaying turbulence
Aditya G. Nair, James Hanna, Matteo Aureli
In two-dimensional decaying homogeneous isotropic turbulence, kinetic energy and enstrophy are respectively transferred to larger and smaller scales. In such spatiotemporally compl…
Quadratic-stretch elasticity
E. Vitral, J. A. Hanna
A nonlinear small-strain elastic theory is constructed from a systematic expansion in Biot strains, truncated at quadratic order. The primary motivation is the desire for a clean s…
Cutting holes in bistable folds
T. Yu, I. Andrade-Silva, M. A. Dias +1
A folded disk is bistable, as it can be popped through to an inverted state with elastic energy localized in a small, highly-deformed region on the fold. Cutting out this singulari…
An integrable family of torqued, damped, rigid rotors
J. A. Hanna
Expositions of the Euler equations for the rotation of a rigid body often invoke the idea of a specially damped system whose energy dissipates while its angular momentum magnitude…
Exact and approximate mechanisms for pure bending of sheets
Tian Yu, J. A. Hanna
Direct measurement of the moment-curvature response of sheets or wires up to high curvatures can aid in modeling creasing, pleating, and other forming operations. We consider theor…
Overcurvature induced multistability of linked conical frusta: How a `bendy straw' holds its shape
Nakul P. Bende, Tian Yu, Nicholas A. Corbin +4
We study the origins of multiple mechanically stable states exhibited by an elastic shell comprising multiple conical frusta, a geometry common to reconfigurable corrugated structu…
Impact-induced acceleration by obstacles
N. A. Corbin, J. A. Hanna, W. R. Royston +2
We explore a surprising phenomenon in which an obstruction accelerates, rather than decelerates, a moving flexible object. It has been claimed that the right kind of discrete chain…
On the planar elastica, stress, and material stress
H. Singh, J. A. Hanna
We revisit the classical problem of the planar Euler \emph{elastica} with applied forces and moments, and present a classification of the shapes in terms of tangentially conserved…
Whirling skirts and rotating cones
Jemal Guven, J A Hanna, Martin Michael Müller
Steady, dihedrally symmetric patterns with sharp peaks may be observed on a spinning skirt, lagging behind the material flow of the fabric. These qualitative features are captured…
Dipoles in thin sheets
Jemal Guven, J. A. Hanna, Osman Kahraman +1
A flat elastic sheet may contain pointlike conical singularities that carry a metrical "charge" of Gaussian curvature. Adding such elementary defects to a sheet allows one to make…
Unwrapping Chains
A. D. Cambou, B. D. Gamari, E. Hamm +4
A loop of chain can move along its own tangents, maintaining a steady shape. An open-ended chain undergoing a nontrivial motion must change its shape. One consequence is that chain…
Surfactant-induced migration of a spherical drop in Stokes flow
James A. Hanna, Petia M. Vlahovska
In Stokes flows, symmetry considerations dictate that a neutrally-buoyant spherical particle will not migrate laterally with respect to the local flow direction. We show that a los…