arXiv subjects

Krishnan Suryanarayanan

Publications and source records attributed to Krishnan Suryanarayanan.

3 recordsLinked to original sources

arXiv2026

Self-contact in a buckled elastica

We explore the mechanics of a terminally loaded buckled elastica under frictionless self-contact. With the aid of two integrals associated with the elastica, we propose a scale-invariant condition necessary for the onset of contact. The condition is independent of the boundary conditions, does not involve the position vectors of the material points, and delivers the value of the compressive load at which self-contact initiates. Furthermore, we show that one of the two integrals, namely the \emph{Hamiltonian}, persists after contact. We compute post-contact configurations of modes three through ten for a pinned-pinned buckled elastica. At a given value of the compressive load, we report multiple post-contact configurations for modes eight and nine. Finally, we show that an infinite force is required to transition from a point contact to a line contact in symmetric post-contact configurations of odd modes.

cond-mat.soft↗

arXiv2026

A theory of locally impenetrable elastic tubes

We present a reduced-order theory for locally impenetrable elastic tubes with uniform circular cross-section. The constraint of local impenetrability is incorporated into a variational scheme to derive a complete set of governing equations, jump conditions, and boundary conditions. We show that when local impenetrability is actively enforced, the configurations of the tube comprise segments of standard Kirchhoff rod solutions appropriately connected to segments of constant Frenet curvature. The theory is illustrated via three examples: a fully flexible tube and an elastic tube, both hanging under self-weight, and a highly twisted elastic tube.

cond-mat.soft↗

arXiv2026

Adhesive tape loops

We present an experimental and theoretical study of the mechanics of an \emph{adhesive tape loop}, formed by bending a straight rectangular strip with adhesive properties, and prescribing an overlap between the two ends. For a given combination of the adhesive strength and the extent of the overlap, the loop may unravel, it may stay in equilibrium, or open up quasi-statically to settle into an equilibrium with a smaller overlap. We define the state space of an adhesive tape loop with two parameters: a non-dimensional adhesion strength, and the extent of overlap normalized by the total length of the loop. We conduct experiments with adhesive tape loops fabricated out of sheets of polydimethylsiloxane (PDMS) and record their states. We rationalize the experimental observations using a simple scaling argument, followed by a detailed theoretical model based on Kirchhoff rod theory. The predictions made by the theoretical model, namely the shape of the loops and the states corresponding to equilibrium, show good agreement with the experimental data. Our model may potentially be used to deduce the strength of self-adhesion in sticky soft materials by simply measuring the smallest overlap needed to maintain a tape loop in equilibrium.

cond-mat.soft↗