Sökning: "a posteriori error estimate"

Visar resultat 16 - 20 av 29 avhandlingar innehållade orden a posteriori error estimate.

  1. 16. Adaptive finite element methods for multiphysics problems

    Författare :Fredrik Bengzon; Mats Larson; Harald van Brummelen; Umeå universitet; []
    Nyckelord :finite element methods; multiphysics; a posteriori error estimation; duality; adaptivity; discontinuous Galerkin; fractional step methods;

    Sammanfattning : In this thesis we develop and analyze the performance ofadaptive finite element methods for multiphysics problems. Inparticular, we propose a methodology for deriving computable errorestimates when solving unidirectionally coupled multiphysics problemsusing segregated finite element solvers. LÄS MER

  3. 17. Goal-Oriented Adaptive Finite Element Analysis in Computational Material Mechanics

    Författare :Fredrik Larsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; visco-plasticity; a posteriori error estimation; thermo-elasticity; mesh refinement; adaptivity; FEM; elasticity;

    Sammanfattning : This thesis is concerned with error control in computational material mechanics. A posteriori error estimation and adaptivity for finite element discretizations is investigated. Based on the technique of solving a dual problem, it is possible to control the accuracy of arbitrary quantities. LÄS MER

  4. 18. Finite element methods for multiscale/multiphysics problems

    Författare :Robert Söderlund; Mats Larson; Victor Ginting; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; finite element methods; variational multiscale methods; Galerkin; convergence analysis; multiphysics; a posteriori error estimation; duality; adaptivity; Mathematical statistics; Matematisk statistik; Mathematical Statistics; matematisk statistik;

    Sammanfattning : In this thesis we focus on multiscale and multiphysics problems. We derive a posteriori error estimates for a one way coupled multiphysics problem, using the dual weighted residual method. LÄS MER

  5. 19. Efficient Adaptive Algorithms for an Electromagnetic Coefficient Inverse Problem

    Författare :John Bondestam Malmberg; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; coefficient inverse problem; inverse scattering; Maxwell’s equations; approximate global convergence; finite element method; adaptivity; ; a posteriori error analysis;

    Sammanfattning : This thesis comprises five scientific papers, all of which are focusing on the inverse problem of reconstructing a dielectric permittivity which may vary in space inside a given domain. The data for the reconstruction consist of time-domain observations of the electric field, resulting from a single incident wave, on a part of the boundary of the domain under consideration. LÄS MER

  7. 20. Computational Characterization of Mixing in Flows

    Författare :Erik D. Svensson; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; mixing; hyperbolicity; shadowing; finite elements; flow simulation; a priori error estimates; Stokes equations; point location; multigrid; refinements; mixing;

    Sammanfattning : The major theme of this thesis is mathematical aspects of fluid mixing in the case when diffusion is negligible, which is commonly refered to as ’mixing by stirring’ or ’mixing by chaotic advection’ in the engineering literature. In this case the mixing is driven by a velocity field and is characterized by the flow generated by the velocity field. LÄS MER