Tube models derived from the basic ideas of De Gennes and Doi & Edwards on reptation of entangled chains have made tremendous progress in the past 30 years and have now reached a quantitative level for the prediction of linear viscoelasticity of linear polymers. After a concise reminder of key experimental features of dynamic moduli, we first review the fundamental ingredients of quantitative t...

We consider a finite-element-in-space, and quadrature-in-timediscretization of a compressible linear quasistatic viscoelasticity problem. The spatial discretization uses a discontinous Galerkin finite element method based on polynomials of degree r—termed DG(r)—and the time discretization uses a trapezoidal-rectangle rule approximation to the Volterra (history) integral. Both semiand fully-disc...

Polyethylene wear is a significant clinical problem in total knee arthroplasty (TKA). Although the tribology of joint replacement has consequently become an area of significant research, the effect of joint fluid on lubrication has been largely overlooked in the replaced joint. One factor that affects the tribology of metal on polyethylene articulation in joint prostheses is mechanical properti...

This article addresses a thermo-mechanically coupled problem of thermo-viscoelasticity at finite strains using a monolithic approach. The underlying equations are based on the non-linear transient heat equation, the local equilibrium conditions and the evolution equations of the internal variables. The latter describe the hardening behavior of the material. If the method of vertical lines is ap...

Average left ventricular (LV) chamber stiffness (Delta P(avg)/Delta V(avg)) is an important diastolic function index. An E-wave-based determination of Delta P(avg)/Delta V(avg) (Little WC, Ohno M, Kitzman DW, Thomas JD, Cheng CP. Circulation 92: 1933-1939, 1995) predicted that deceleration time (DT) determines stiffness as follows: Delta P(avg)/Delta V(avg) = N(pi/DT)(2) (where N is constant), ...