Sökning: "Finite element method"

Visar resultat 6 - 10 av 857 avhandlingar innehållade orden Finite element method.

  1. 6. A hybrid finite element method for electromagnetics with applications in time-domain

    Författare :DAVID DEGERFELDT; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Nitsche s method; antenna arrays; NASA almond; edge elements; scattering; explicit-implicit time-stepping; Maxwell s equations; Finite Element Method; mass lumping; stability analysis; Finite-Differences Time-Domain; periodic structures; shape and material optimization;

    Sammanfattning : In this thesis, a new hybrid method that combines the Finite Element Method (FEM) with the Finite-Difference in Time-Domain (FDTD) method is presented. Tetrahedrons in the unstructured FEM region are connected directly to thehexahedrons in the structured FDTD region. LÄS MER

  3. 7. Multigrid Preconditioners for the Discontinuous Galerkin Spectral Element Method : Construction and Analysis

    Författare :Lea Miko Versbach; Numerisk analys; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Discontinuous Galerkin Method; Finite Volume Method; Implicit Schemes; Local Fourier Analysis; Multigrid Method; Preconditioner; Space-Time Discretization; Spectral Element Method;

    Sammanfattning : Discontinuous Galerkin (DG) methods offer a great potential for simulations of turbulent and wall bounded flows with complex geometries since these high-order schemes offer a great potential in handling eddies. Recently, space-time DG methods have become more popular. LÄS MER

  4. 8. Efficient Solvers for Space-Time Discontinuous Galerkin Spectral Element Methods

    Författare :Lea Miko Versbach; Numerisk analys; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Discontinuous Galerkin Method; Spectral Element Method; Finite Volume Method; Implicit Schemes; Preconditioner; Multigrid Method; Space-Time; Lobatto IIIC Method; Local Fourier Analysis;

    Sammanfattning : In this thesis we study efficient solvers for space-time discontinuous Galerkin spectral element methods (DG-SEM). These discretizations result in fully implicit schemes of variable order in both spatial and temporal directions. LÄS MER

  5. 9. Adaptive Finite Element Procedures in Structural Dynamics

    Författare :Xiangdong Li; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; finite element; h-adaptivity; Newmark method; structural dynamics; space-time; a posteriori; superconvergent patch recovery; postprocessing; automatic time-stepping; semidiscretization; error estimation; discontinuous Galerkin;

    Sammanfattning : This thesis deals with a posteriori error estimation and adaptivity in finite element procedures for the analysis of structural dynamic problems. First, error estimation and adaptivity for the Newmark time integration method are studied. LÄS MER

  7. 10. The material distribution method : analysis and acoustics applications

    Författare :Fotios Kasolis; Martin Berggren; Volker Schulz; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Material distribution method; fictitious domain method; finite element method; Helmholtz equation; linear elasticity; shape optimization; topology optimization;

    Sammanfattning : For the purpose of numerically simulating continuum mechanical structures, different types of material may be represented by the extreme values {,1}, where 0.... LÄS MER