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Numerical simulation of a viscoelastic fluid with a preconditioned Schwarz method

Luís Borges, Adélia Sequeira (2008)

Banach Center Publications

In this paper we apply a domain decomposition method to approach the solution of a non-Newtonian viscoelastic Oldroyd-B model. The numerical scheme is based on a fixed-point argument applied to the original non-linear system of partial differential equations decoupled into a Navier-Stokes system and a tensorial transport equation. Using a modified Schwarz algorithm, involving block preconditioners for the Navier-Stokes equations, the decoupled problems are solved iteratively. Numerical simulations...

Numerical simulation of blood flows through a porous interface

Miguel A. Fernández, Jean-Frédéric Gerbeau, Vincent Martin (2008)

ESAIM: Mathematical Modelling and Numerical Analysis

We propose a model for a medical device, called a stent, designed for the treatment of cerebral aneurysms. The stent consists of a grid, immersed in the blood flow and located at the inlet of the aneurysm. It aims at promoting a clot within the aneurysm. The blood flow is modelled by the incompressible Navier-Stokes equations and the stent by a dissipative surface term. We propose a stabilized finite element method for this model and we analyse its convergence in the case of the Stokes...

Numerical simulation of flow induced airfoil vibrations with large amplitudes

Winter, Ondřej, Sváček, Petr (2019)

Programs and Algorithms of Numerical Mathematics

This paper is interested with the numerical simulation of the fluid-structure interaction problem realized with the aid of the OpenFOAM package. The case of flow past oscillating NACA 0012 profile was chosen. The loose, strong and combined strong coupling algorithms were tested. The results are presented and a significant improvement of the combined coupling algorithm is shown.

Numerical simulation of free-surface flows with surface tension

Sváček, Petr (2015)

Programs and Algorithms of Numerical Mathematics

This paper focuses on the mathematical modelling and the numerical approximation of the flow of two immiscible incompressible fluids. The surface tension effects are taken into account and mixed boundary conditions are used. The weak formulation is introduced, discretized in time, and the finite element method is applied. The free surface motion is treated with the aid of the level set method. The numerical results are shown.

Numerical simulation of generalized Newtonian and Oldroyd-B fluids flow

Keslerová, Radka, Kozel, Karel (2013)

Programs and Algorithms of Numerical Mathematics

This work deals with the numerical solution of generalized Newtonian and Oldroyd-B fluids flow. The governing system of equations is based on the system of balance laws for mass and momentum for incompressible laminar viscous and viscoelastic fluids. Two different definition of the stress tensor are considered. For viscous case Newtonian model is used. For the viscoelastic case Oldroyd-B model is tested. Both presented models can be generalized. In this case the viscosity is defined as a shear rate...

Numerical simulation of generalized Newtonian fluids flow in bypass geometry

Keslerová, Radka, Řezníček, Hynek, Padělek, Tomáš (2019)

Programs and Algorithms of Numerical Mathematics

The aim of this work is to present numerical results of non-Newtonian fluid flow in a model of bypass. Different angle of a connection between narrowed channel and the bypass graft is considered. Several rheology viscosity models were used for the non-Newtonian fluid, namely the modified Cross model and the Carreau-Yasuda model. The results of non-Newtonian fluid flow are compared to the results of Newtonian fluid. The fundamental system of equations is the generalized system of Navier-Stokes equations...

Numerical simulation of gluey particles

Aline Lefebvre (2009)

ESAIM: Mathematical Modelling and Numerical Analysis - Modélisation Mathématique et Analyse Numérique

We propose here a model and a numerical scheme to compute the motion of rigid particles interacting through the lubrication force. In the case of a particle approaching a plane, we propose an algorithm and prove its convergence towards the solutions to the gluey particle model described in [B. Maury, ESAIM: Proceedings 18 (2007) 133–142]. We propose a multi-particle version of this gluey model which is based on the projection of the velocities onto a set of admissible velocities. Then, we describe...

Numerical simulation of gluey particles

Aline Lefebvre (2008)

ESAIM: Mathematical Modelling and Numerical Analysis

We propose here a model and a numerical scheme to compute the motion of rigid particles interacting through the lubrication force. In the case of a particle approaching a plane, we propose an algorithm and prove its convergence towards the solutions to the gluey particle model described in [B. Maury, ESAIM: Proceedings18 (2007) 133–142]. We propose a multi-particle version of this gluey model which is based on the projection of the velocities onto a set of admissible velocities. Then, we describe...

Numerical simulation of surface acoustic wave actuated cell sorting

Thomas Franke, Ronald Hoppe, Christopher Linsenmann, Kidist Zeleke (2013)

Open Mathematics

We consider the mathematical modeling and numerical simulation of high throughput sorting of two different types of biological cells (type I and type II) by a biomedical micro-electro-mechanical system (BioMEMS) whose operating behavior relies on surface acoustic wave (SAW) manipulated fluid flow in a microchannel. The BioMEMS consists of a separation channel with three inflow channels for injection of the carrier fluid and the cells, two outflow channels for separation, and an interdigital transducer...

Numerical simulation of suspension induced rheology

Rodolphe Prignitz, Eberhard Bänsch (2010)

Kybernetika

Flow of particles suspended in a fluid can be found in numerous industrial processes utilizing sedimentation, fluidization and lubricated transport such as food processing, catalytic processing, slurries, coating, paper manufacturing, particle injection molding and filter operation. The ability to understand rheology effects of particulate flows is elementary for the design, operation and efficiency of the underlying processes. Despite the fact that particle technology is widely used, it is still...

Numerical simulation of the motion of a three-dimensional glacier

Marco Picasso, Jacques Rappaz, Adrian Reist (2008)

Annales mathématiques Blaise Pascal

The motion of a three-dimensional glacier is considered. Ice is modeled as an incompressible non-Newtonian fluid. At each time step, given the shape of the glacier, a nonlinear elliptic system has to be solved in order to obtain the two components of the horizontal velocity field. Then, the shape of the glacier is updated by solving a transport equation. Finite element techniques are used to compute the velocity field and to solve the transport equation. Numerical results are compared to experiments...

Numerical simulations of wave breaking

Philippe Helluy, Frédéric Golay, Jean-Paul Caltagirone, Pierre Lubin, Stéphane Vincent, Deborah Drevard, Richard Marcer, Philippe Fraunié, Nicolas Seguin, Stephan Grilli, Anne-Cécile Lesage, Alain Dervieux, Olivier Allain (2005)

ESAIM: Mathematical Modelling and Numerical Analysis - Modélisation Mathématique et Analyse Numérique

This paper is devoted to the numerical simulation of wave breaking. It presents the results of a numerical workshop that was held during the conference LOMA04. The objective is to compare several mathematical models (compressible or incompressible) and associated numerical methods to compute the flow field during a wave breaking over a reef. The methods will also be compared with experiments.

Numerical simulations of wave breaking

Philippe Helluy, Frédéric Golay, Jean-Paul Caltagirone, Pierre Lubin, Stéphane Vincent, Deborah Drevard, Richard Marcer, Philippe Fraunié, Nicolas Seguin, Stephan Grilli, Anne-Cécile Lesage, Alain Dervieux, Olivier Allain (2010)

ESAIM: Mathematical Modelling and Numerical Analysis

This paper is devoted to the numerical simulation of wave breaking. It presents the results of a numerical workshop that was held during the conference LOMA04. The objective is to compare several mathematical models (compressible or incompressible) and associated numerical methods to compute the flow field during a wave breaking over a reef. The methods will also be compared with experiments.

Numerical solution of a 1-d elastohydrodynamic problem in magnetic storage devices

Iñigo Arregui, José Jesús Cendán, Carlos Parés, Carlos Vázquez (2008)

ESAIM: Mathematical Modelling and Numerical Analysis

In this work we present new numerical methods to simulate the mechanics of head-tape magnetic storage devices. The elastohydrodynamic problem is formulated in terms of a coupled system which is governed by a nonlinear compressible Reynolds equation for the air pressure over the head, and a rod model for the tape displacement. A fixed point algorithm between the solutions of the elastic and hydrodynamic problems is proposed. For the nonlinear Reynolds equation, a characteristics method and a...

Currently displaying 121 – 140 of 161