In previous work it was shown that a class of axisymmetric viscoelastic membrane problems can be reduced to the numerical solution of a system of partial differential-Volterra integral equations. This general method has the disadvantage that a change in constitutive equation requires rederivation of specific details of the governing system. In this paper, a revised method is presented in which ...

We report here the first experimental measurements of nonlinear rheological material properties of hagfish slime, a hydrated biopolymer/biofiber network, and develop a microstructural constitutive model to explain the observed nonlinear viscoelastic behavior. The linear elastic modulus of the network is observed to be G′ ≈ 0.02 Pa for timescales 0.1 s ≤ t ≤ 10 s, making it one of the softest el...

This paper presents a new and efficient method for computing the flow of a non-Newtonian fluid. The approach is based on two independent concepts: Time-dependent simulation of viscoelastic flow: A new decoupled algorithm, presented in P. Saramito, Simulation numerique d'ecoulements de fluides viscoelastiques par eRments finis incompressibles et une methode de directions alternees; applications,...

Bulk rheological properties of viscoelastic fluids have been extensively studied in macroscopic shearing geometries. However, little is known when an active microscopic probe is used to locally perturb them far from the linear-response regime. Using a colloidal particle dragged periodically by scanning optical tweezers through a viscoelastic fluid, we investigate both, its linear and nonlinear ...

The numerical simulation of viscoelastic fluid flow becomes more difficult as a physical parameter, the Weissenberg number, increases. Specifically, at a Weissenberg number larger than a critical value, the iterative nonlinear solver fails to converge, a phenomenon known as the High Weissenberg Number Problem. In this work we describe the application and implementation of continuation methods t...

A simple model for a swimmer consisting of three colinearly linked spheres attached by rods and oscillating out of phase to break reciprocal motion is analyzed. With a prescribed forcing of the rods acting on the three spheres, the swimming dynamics are determined analytically in both a Newtonian Stokes fluid and a zero Reynolds number, nonlinear, Oldroyd-B viscoelastic fluid with Deborah numbe...

The present work reports a discrete stress-dependent, complex compliance spectra method that may be used to predict the mechanical response of nonlinear viscoelastic polymers during creep and recovery processes. The method is based on the observation that the real and imaginary parts of a discrete complex compliance frequency spectra obtained from creep and recovery measurements are smooth, eas...