FINITE ELEMENT METHOD-BASED SOLUTION OF ELASTIC PROBLEM. STRESS TENSOR VISUALIZATION

In this paper, non-Newtonian viscoelastic Oldroyd-B fluid flows in two-dimensional rectangular domain is numerically investigated, where the flow between two rigid walls is driven by a pressure difference along -direction (horizontal). The numerical results of the nonlinear system of partial differential equations are obtained by decoupling the system into Navier-Stokes system and tensorial transport equation. Computational Fluid Dynamics (CFD) simulations are done by using the finite element method. The numerical simulations are presented in terms of the contours of velocity, pressure and extra stress tensor. The Hood-Taylor finite element method is used for the approximation of the velocity and the pressure while the discontinuous Galerkin method is used to approximate the stress tensor. All the meshes and simulations are carried out by the general finite element solver FreeFem++, which has been found as a potential tool to provide a reasonably good numerical simulations of complicated flow behavior.

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Viscoelastic Effects on Drop Deformation Using a Machine Learning-Enhanced, Finite Element method

Polymers ◽

10.3390/polym12081652 ◽

2020 ◽

Vol 12 (8) ◽

pp. 1652

Author(s):

Juan Luis Prieto

Keyword(s):

Machine Learning ◽

Finite Element Method ◽

Finite Element ◽

Stress Tensor ◽

Numerical Study ◽

Dynamics Simulation ◽

Machine Learning Techniques ◽

Drop Deformation ◽

Viscoelastic Effects ◽

Element Method

This paper presents a numerical study of the viscoelastic effects on drop deformation under two configurations of interest: steady shear flow and complex flow under gravitational effects. We use a finite element method along with Brownian dynamics simulation techniques that avoid the use of closed-form, constitutive equations for the “micro-”scale, studying the viscoelastic effects on drop deformation using an interface capturing technique. The method can be enhanced with a variance-reduced approach to the stochastic modeling, along with machine learning techniques to reconstruct the shape of the polymer stress tensor in complex problems where deformations can be dramatic. The results highlight the effects of viscoelasticity on shape, the polymer stress tensor, and flow streamlines under the analyzed configurations.

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Numerical modelling of nonlinear electromechanical coupling of an atomic force microscope with finite element method

Advances in Radio Science ◽

10.5194/ars-8-33-2010 ◽

2010 ◽

Vol 8 ◽

pp. 33-36 ◽

Cited By ~ 1

Author(s):

J. Freitag ◽

W. Mathis

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Atomic Force Microscope ◽

Stress Tensor ◽

Electromechanical Coupling ◽

Maxwell Stress ◽

Maxwell Stress Tensor ◽

Atomic Force ◽

Monolithic Approach ◽

Element Method

Abstract. In this contribution, an atomic force microscope is modelled and in this context, a non-linear coupled 3-D-boundary value problem is solved numerically using the finite element method. The coupling of this system is done by using the Maxwell stress tensor. In general, an iterative weak coupling is used, where the two physical problems are solved separately. However, this method does not necessarily guarantee convergence of the nonlinear computation. Hence, this contribution shows the possibility of solving the multiphysical problem by a strong coupling, which is also referred to as monolithic approach. The electrostatic field and the mechanical displacements are calculated simultaneously by solving only one system of equation. Since the Maxwell stress tensor depends nonlinearly on the potential, the solution is solved iteratively by the Newton method.

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Simulation of tuning graphene plasmonic behaviors by ferroelectric domains for self-driven infrared photodetector applications

Nanoscale ◽

10.1039/c9nr06508c ◽

2019 ◽

Vol 11 (43) ◽

pp. 20868-20875 ◽

Cited By ~ 1

Author(s):

Junxiong Guo ◽

Yu Liu ◽

Yuan Lin ◽

Yu Tian ◽

Jinxing Zhang ◽

...

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Interfacial Effect ◽

Infrared Photodetector ◽

The Finite Element Method ◽

Ferroelectric Domains ◽

Element Method

We propose a graphene plasmonic infrared photodetector tuned by ferroelectric domains and investigate the interfacial effect using the finite element method.

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