Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Multi-grid methods for stokes and navier-stokes equations (1989)
    Springer
    Numerische Mathematik 54 (1989), S. 543-563 
    Details
    ISSN: 0945-3245
    Keywords: AMS(MOS):65N20 ; CR:G1.8
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Summary In the present paper we introduce transforming iterations, an approach to construct smoothers for indefinite systems. This turns out to be a convenient tool to classify several well-known smoothing iterations for Stokes and Navier-Stokes equations and to predict their convergence behaviour, epecially in the case of high Reynolds-numbers. Using this approach, we are able to construct a new smoother for the Navier-Stokes equations, based on incomplete LU-decompositions, yielding a highly effective and robust multi-grid method. Besides some qualitative theoretical convergence results, we give large numerical comparisons and tests for the Stokes as well as for the Navier-Stokes equations. For a general convergence theory we refer to [29].
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01396361
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Shifted iterations (1997)
    Springer
    Numerische Mathematik 76 (1997), S. 265-278 
    Details
    ISSN: 0945-3245
    Keywords: Mathematics Subject Classification (1991):65N55
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002110050263
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Schur-complement multigrid (1997)
    Springer
    Numerische Mathematik 75 (1997), S. 523-545 
    Details
    ISSN: 0945-3245
    Keywords: Mathematics Subject Classification (1991):65N55
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Summary. A Schur-complement multigrid method for the solution of convection-diffusion problems with strongly discontinuous coefficients is the focus of this paper. This algorithm turns out to be robust and efficient for our test problems. Its convergence rate is in all cases superior to the standard multigrid method. The Schur-complement multigrid method is applied to the problem of the decontamination of a heterogeneous porous medium by flushing. We determine the typical decontamination time for several configurations and its functional dependence on the statistical properties of the hydraulic conductivity distribution of the medium.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002110050251
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Robust iterative methods for elliptic problems with highly varying coefficients in thin substructures (1996)
    Springer
    Numerische Mathematik 73 (1996), S. 449-472 
    Details
    ISSN: 0945-3245
    Keywords: Mathematics Subject Classification (1991):65F10, 65N20, 65N30
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Summary. In this paper we introduce a class of robust multilevel interface solvers for two-dimensional finite element discrete elliptic problems with highly varying coefficients corresponding to geometric decompositions by a tensor product of strongly non-uniform meshes. The global iterations convergence rate $q〈1$ is shown to be of the order $q = 1 - O (\log^{-1/2}n)$ with respect to the number $n$ of degrees of freedom on the single subdomain boundaries, uniformly upon the coarse and fine mesh sizes, jumps in the coefficients and aspect ratios of substructures. As the first approach, we adapt the frequency filtering techniques [28] to construct robust smoothers on the highly non-uniform coarse grid. As an alternative, a multilevel averaging procedure for successive coarse grid correction is proposed and analyzed. The resultant multilevel coarse grid preconditioner is shown to have (in a two level case) the condition number independent of the coarse mesh grading and jumps in the coefficients related to the coarsest refinement level. The proposed technique exhibited high serial and parallel performance in the skin diffusion processes modelling [20] where the high dimensional coarse mesh problem inherits a strong geometrical and coefficients anisotropy. The approach may be also applied to magnetostatics problems as well as in some composite materials simulation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002110050200
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...