The Casimir attraction can significantly interfere the physical response of nanoactuators. The intensity of the Casimir force depends on the geometries of interacting bodies. The present paper is dedicated to model the influence of the Casimir attraction on the electrostatic stability of nanoactuators made of cylindrical conductive nanowire/nanotube. An asymptotic solution, based on path-integr...

We study a dynamic model for viscoelastic materials based on a constitutive equation of fractional order. This results in an integrodifferential equation with a weakly singular convolution kernel. We discretize in the spatial variable by a standard Galerkin finite element method. We prove stability and regularity estimates which show how the convolution term introduces dissipation into the equa...

In order to develop a constitutive equation for foamed polymer solutions their flow behavior was investigated in a large-scale vertical tube. Starting from theoretical considerations, two new constitutive equations are proposed. A new variable+the specif;c t&me expansion mti+is introduced to characterize the relative gas content of the foam. With the new variable the proposed constitutive equat...

A single correlation for sand erosion of a “family” of polyurethanes is presented. By “family” is meant a group of chemically similar compounds. For the first time, an implication of Truesdell’s [1] observations regarding the number of dimensional parameters in viscoelastic constitutive equations has been used together with the Pi theorem to prepare a single dimensionless correlation for a grou...

Electro-active solids are solids that are either infused with electrorheological fluids or embedded with electrically conducting particles, the body as a whole however conducting negligible current. In this paper, we provide a mathematical framework, within the context of continuum mechanics, for the study of electro-active solids. The theory assumes that the body can be considered as a continu...

4 constitutive equation for unstimulated muscle based on nonlinear elastic and linear damping elements is proposed. This equation is solved in closed form to predict creep and stress relaxation in passive muscle and. if combined with an active contractile element in a three-element model. initial response to a sudden change in length or force during an isometric twitch. A stress relaxation expe...

Recent research by Xing [Phys. Rev. Lett. 98, 075502 (2007)] has provided an expression for the Helmholtz free energy related to phonon fluctuations in polymer networks. We extend this result by constructing the corresponding nonlinear constitutive equation, usable for entirely general, volume conserving deformation fields. Constitutive equations for the sliplink model and the tube model are de...

[1] A generalized constitutive equation for bubbly liquids is presented which successfully reproduces the expected viscosity response for both steady flows with varying capillary number Ca (a measure of the bubble deformation) and unsteady flows with varying dynamic capillary number Cd (a measure of the steadiness of the flow) previously given in separate studies. The constitutive equation is g...

We solve exactly and describe in detail a simplified scalar model for the low frequency shear rheology of foams, emulsions, slurries, etc. @P. Sollich, F. Lequeux, P. Hébraud, and M. E. Cates, Phys. Rev. Lett. 78, 2020 ~1997!#. The model attributes similarities in the rheology of such ‘‘soft glassy materials’’ to the shared features of structural disorder and metastability. By focusing on the d...