an experiment featuring waterhammer in viscoelastic pipes is presented in which the effects of pipe-wall viscoelasticity on waterhammer pressures are investigated. a large-scale pipeline apparatus made of polyvinyl chloride (pvc) at deltares, delft, the netherlands, has been used to carry out waterhammer experiments. tests have been conducted in a reservoir-pipeline-valve system consisting of a...

Owing to nonlinear viscoelasticity, materials often show characteristic features that resemble those of thixotropy. This issue has been debated in the literature over past several decades, and experimental protocols have proposed distinguish thixotropy from viscoelasticity. In this work, we assess these by carrying out experiments using polymer solutions, thixotropic clay dispersions, modeling ...

The result of Da Prato and Sinestrari [3] concerning the non-autonomous evolution operators of hyperbolic type for the equation u′(t) = A(t)u(t) + f(t), t ∈ [0, T ], w(0) = w0, is applied to the study of u′(t) = A(t) [ u(t)+ ∫ t −∞ G(t, s)u(s)ds ] +K(t)u(t)+f(t), t ∈ [0, T ], u(s) = φ(s), s ≤ 0, which models linear viscoelasticity. Here A(·) satisfies all the requirements of Kato’s semigroup ap...

To determine whether and to what extent one component of the extracellular matrix, fibrillar collagen, contributes causally to abnormalities in viscoelasticity, collagen was acutely degraded by activation of endogenous matrix metalloproteinases (MMPs) with the serine protease plasmin. Papillary muscles were isolated from normal cats and cats with right ventricular pressure overload hypertrophy ...