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Staggered schemes for all speed flows

Raphaèle Herbin, Walid Kheriji, Jean-Claude Latche (2012)

ESAIM: Proceedings

We review in this paper a class of schemes for the numerical simulation of compressible flows. In order to ensure the stability of the discretizations in a wide range of Mach numbers and introduce sufficient decoupling for the numerical resolution, we choose to implement and study pressure correction schemes on staggered meshes. The implicit version of the schemes is also considered for the theoretical study. We give both algorithms for the barotropic Navier-Stokes equations, for the full Navier-Stokes...

Steady compressible Oseen flow with slip boundary conditions

Tomasz Piasecki (2009)

Banach Center Publications

We prove the existence of solution in the class H²(Ω) × H¹(Ω) to the steady compressible Oseen system with slip boundary conditions in a two dimensional, convex domain with boundary of class H 5 / 2 . The method is to regularize a weak solution obtained via the Galerkin method. The problem of regularization is reduced to the problem of solvability of a certain transport equation by application of the Helmholtz decomposition. The method works under an additional assumption on the geometry of the boundary....

Stick-slip transition capturing by using an adaptive finite element method

Nicolas Roquet, Pierre Saramito (2004)

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

The numerical modeling of the fully developed Poiseuille flow of a newtonian fluid in a square section with slip yield boundary condition at the wall is presented. The stick regions in outer corners and the slip region in the center of the pipe faces are exhibited. Numerical computations cover the complete range of the dimensionless number describing the slip yield effect, from a full slip to a full stick flow regime. The resolution of variational inequalities describing the flow is based on the...

Stick-slip transition capturing by using an adaptive finite element method

Nicolas Roquet, Pierre Saramito (2010)

ESAIM: Mathematical Modelling and Numerical Analysis

The numerical modeling of the fully developed Poiseuille flow of a Newtonian fluid in a square section with slip yield boundary condition at the wall is presented. The stick regions in outer corners and the slip region in the center of the pipe faces are exhibited. Numerical computations cover the complete range of the dimensionless number describing the slip yield effect, from a full slip to a full stick flow regime. The resolution of variational inequalities describing the flow is based on the...

The generalized finite volume SUSHI scheme for the discretization of the peaceman model

Mohamed Mandari, Mohamed Rhoudaf, Ouafa Soualhi (2021)

Applications of Mathematics

We demonstrate some a priori estimates of a scheme using stabilization and hybrid interfaces applying to partial differential equations describing miscible displacement in porous media. This system is made of two coupled equations: an anisotropic diffusion equation on the pressure and a convection-diffusion-dispersion equation on the concentration of invading fluid. The anisotropic diffusion operators in both equations require special care while discretizing by a finite volume method SUSHI. Later,...

The Mortar finite element method for Bingham fluids

Patrick Hild (2001)

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

This paper deals with the flow problem of a viscous plastic fluid in a cylindrical pipe. In order to approximate this problem governed by a variational inequality, we apply the nonconforming mortar finite element method. By using appropriate techniques, we are able to prove the convergence of the method and to obtain the same convergence rate as in the conforming case.

The mortar finite element method for Bingham fluids

Patrick Hild (2010)

ESAIM: Mathematical Modelling and Numerical Analysis

This paper deals with the flow problem of a viscous plastic fluid in a cylindrical pipe. In order to approximate this problem governed by a variational inequality, we apply the nonconforming mortar finite element method. By using appropriate techniques, we are able to prove the convergence of the method and to obtain the same convergence rate as in the conforming case.

The Rothe method and time periodic solutions to the Navier-Stokes equations and equations of magnetohydrodynamics

Dana Lauerová (1990)

Aplikace matematiky

The existence of a periodic solution of a nonlinear equation z ' + A 0 z + B 0 z = F is proved. The theory developed may be used to prove the existence of a periodic solution of the variational formulation of the Navier-Stokes equations or the equations of magnetohydrodynamics. The proof of the main existence theorem is based on Rothe method in combination with the Galerkin method, using the Brouwer fixed point theorem.

Two-grid finite-element schemes for the transient Navier-Stokes problem

Vivette Girault, Jacques-Louis Lions (2001)

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

We semi-discretize in space a time-dependent Navier-Stokes system on a three-dimensional polyhedron by finite-elements schemes defined on two grids. In the first step, the fully non-linear problem is semi-discretized on a coarse grid, with mesh-size H . In the second step, the problem is linearized by substituting into the non-linear term, the velocity 𝐮 H computed at step one, and the linearized problem is semi-discretized on a fine grid with mesh-size h . This approach is motivated by the fact that,...

Two-grid finite-element schemes for the transient Navier-Stokes problem

Vivette Girault, Jacques-Louis Lions (2010)

ESAIM: Mathematical Modelling and Numerical Analysis

We semi-discretize in space a time-dependent Navier-Stokes system on a three-dimensional polyhedron by finite-elements schemes defined on two grids. In the first step, the fully non-linear problem is semi-discretized on a coarse grid, with mesh-size H. In the second step, the problem is linearized by substituting into the non-linear term, the velocity uH computed at step one, and the linearized problem is semi-discretized on a fine grid with mesh-size h. This approach is motivated by the fact that,...

Two-level stabilized nonconforming finite element method for the Stokes equations

Haiyan Su, Pengzhan Huang, Xinlong Feng (2013)

Applications of Mathematics

In this article, we present a new two-level stabilized nonconforming finite elements method for the two dimensional Stokes problem. This method is based on a local Gauss integration technique and the mixed nonconforming finite element of the N C P 1 - P 1 pair (nonconforming linear element for the velocity, conforming linear element for the pressure). The two-level stabilized finite element method involves solving a small stabilized Stokes problem on a coarse mesh with mesh size H and a large stabilized Stokes...

Uncertainty quantification for data assimilation in a steady incompressible Navier-Stokes problem

Marta D’Elia, Alessandro Veneziani (2013)

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

The reliable and effective assimilation of measurements and numerical simulations in engineering applications involving computational fluid dynamics is an emerging problem as soon as new devices provide more data. In this paper we are mainly driven by hemodynamics applications, a field where the progressive increment of measures and numerical tools makes this problem particularly up-to-date. We adopt a Bayesian approach to the inclusion of noisy data in the incompressible steady Navier-Stokes equations...

Uniformly stable mixed hp-finite elements on multilevel adaptive grids with hanging nodes

Friedhelm Schieweck (2008)

ESAIM: Mathematical Modelling and Numerical Analysis

We consider a family of quadrilateral or hexahedral mixed hp-finite elements for an incompressible flow problem with Qr-elements for the velocity and discontinuous P r - 1 -elements for the pressure where the order r can vary from element to element between 2 and an arbitrary bound. For multilevel adaptive grids with hanging nodes and a sufficiently small mesh size, we prove the inf-sup condition uniformly with respect to the mesh size and the polynomial degree.

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