The sonoelastographic theory of tumor detection predicts enhanced image contrast as vibration frequency increases. However, the opposite effect is observed when imaging liver lesions at frequencies (200-400 Hz) where strong viscoelastic effects dominate. Mechanical testing was performed and confirmed the viscoelasticity of liver tissue. The time dependence of the stress relaxation suggests a vi...

An exact two-dimensional rotation-strain model describing the motion of Hookean incompressible viscoelastic materials is constructed by the polar decomposition of the deformation tensor. The global existence of classical solutions is proved under the smallness assumptions only on the size of initial strain tensor. The proof of global existence utilizes the weak dissipative mechanism of motion, ...

The standard step-hold load-relaxation profile can yield variable estimates of mechanical properties due to the difficulty in achieving a step strain experimentally. A ramp-hold profile overcomes this limitation if appropriate model functions can be derived. Utilizing Boltzmann hereditary integral operators for two indentation geometries, analytical ramp solutions for load-relaxation were devel...

In this paper we present a layerwise finite element model for the analysis of sandwich laminated plates with a viscoelastic core and laminated anisotropic face layers. The stiffness and mass matrices of the element are obtained by the Carrera’s Unified formulation (CUF). The dynamic problem is solved in the frequency domain with viscoelastic frequency-dependent material properties for the core....

Physics-informed neural networks (PINN) can be used to predict flow fields with a minimum of simulated or measured training data. As most technical flows are turbulent, PINNs based on the Reynolds-averaged Navier–Stokes (RANS) equations incorporating turbulence model needed. Several studies demonstrated capability solve Naver–Stokes for laminar flows. However, little work has been published con...

This paper is concerned with the numerical simulation of gas flow inside spray dryers, which is known to be highly transient. Experimental evidence presented in the literature to date is acquired either at a scale much smaller than industrial or at a limited number of locations in the system (e.g. the central axis). Alternatively, computational fluid dynamics (CFD) simulation, in particular met...

Reynolds-averaged Navier–Stokes simulations have been performed of the turbulent flow (Re=48000) through a tight lattice (P/D=1.194) subchannel typical those found in nuclear thermal–hydraulic applications. A wide range turbulence models (linear eddy-viscosity, non-linear eddy-viscosity and stress-transport) use different near-wall treatments, including low-Re models, standard wall-functions mo...

BACKGROUND Despite their notorious diversity, biological cells are mechanically well characterized by only a few robust and universal laws. Intriguingly, the law characterizing the nonlinear response to stretch appears self-contradictory. Various cell types have been reported to both stiffen and soften, or "fluidize" upon stretch. Within the classical paradigm of cells as viscoelastic bodies, t...