In this paper, a Dirichlet-Neumann substructuring domain decomposition method is presented for a finite element approximation to the nonlinear Navier-Stokes equations. It is shown that the Dirichlet-Neumann domain decomposition sequence converges geometrically to the true solution provided the Reynolds number is sufficiently small. In this method, subdomain problems are linear. Other version where the subdomain problems are linear Stokes problems is also presented.
In this paper, a Dirichlet-Neumann substructuring domain
decomposition method is presented for a finite element
approximation to the nonlinear Navier-Stokes equations. It is
shown that the Dirichlet-Neumann domain decomposition sequence
converges geometrically to the true solution provided the Reynolds
number is sufficiently small. In this method, subdomain problems
are linear. Other version where the subdomain problems are linear
Stokes problems is also presented.
Different choices of the averaging operator within the BDDC method are compared on a series of 2D experiments.
Subdomains with irregular interface and with jumps in material coefficients are included into the study. Two new approaches are studied along three standard choices. No approach is shown to be universally superior to others, and the resulting recommendation is that an actual method should be chosen based on properties of the problem.
Tuning the alternating Schwarz method to the exterior problems is the subject of this paper. We present the original algorithm and we propose a modification of it, so that the solution of the subproblem involving the condition at infinity has an explicit integral representation formulas while the solution of the other subproblem, set in a bounded domain, is approximated by classical variational methods. We investigate many of the advantages of the new Schwarz approach: a geometrical convergence...
Tuning the alternating Schwarz method to the
exterior problems is the subject of this paper.
We present the original algorithm
and we propose a modification of it, so that the
solution of the subproblem involving the condition at infinity
has an explicit integral representation formulas while the solution
of the other subproblem, set in a bounded domain,
is approximated by classical variational methods.
We investigate many of the advantages of the new
Schwarz approach: a geometrical convergence...
PERMON (Parallel, Efficient, Robust, Modular, Object-oriented, Numerical) is a newly emerging collection of software libraries, uniquely combining Quadratic Programming (QP) algorithms and Domain Decomposition Methods (DDM). Among the main applications are contact problems of mechanics. This paper gives an overview of PERMON and selected ingredients improving scalability, demonstrated by numerical experiments.
Penalty methods, augmented Lagrangian methods and Nitsche mortaring are well known numerical methods among the specialists in the related areas optimization and finite elements, respectively, but common aspects are rarely available. The aim of the present paper is to describe these methods from a unifying optimization perspective and to highlight some common features of them.
We present here a new proof of the theorem of
Birman and Solomyak on the metric entropy of the unit ball of a
Besov space on a regular domain of The
result is: if s - d(1/π - 1/p)+> 0, then the Kolmogorov metric
entropy satisfies H(ε) ~ ε-d/s. This proof
takes advantage of the representation of such spaces on wavelet type
bases and extends the result to more general spaces. The lower bound
is a consequence of very simple probabilistic exponential
inequalities. To prove the upper bound,...
We present here a new proof of the theorem of Birman and Solomyak on the metric entropy of the unit ball of a Besov space on a regular domain of The result is: if then the Kolmogorov metric entropy satisfies . This...
This paper introduces the application of asynchronous iterations theory within the framework of the primal Schur domain decomposition method. A suitable relaxation scheme is designed, whose asynchronous convergence is established under classical spectral radius conditions. For the usual case where local Schur complement matrices are not constructed, suitable splittings based only on explicitly generated matrices are provided. Numerical experiments are conducted on a supercomputer for both Poisson's...