Sökning: "Spectral finite element method"

Visar resultat 1 - 5 av 27 avhandlingar innehållade orden Spectral finite element method.

1. 1. 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

3. 2. 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. 3. Waveguide Finite Elements Applied on a Car Tyre

   Författare :Carl-Magnus Nilsson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; wave equation; wave solution; waveguide; finite element; spectral finite element; tyre noise; tyre vibration; input power; shells; pre stress; fluid shell coupling; axi--symmetric;

   Sammanfattning : Structures acting as waveguides are quite common withexamples being, construction beams, fluid filled pipes, railsand extruded aluminium profiles. Curved structures like cartyres and pipe-bends may also be considered as waveguides. Wavesolutions in such structures may be found by a method calledthe Waveguide Finite Element Method or WFEM. LÄS MER

5. 4. Simulation of individual cells in flow

   Författare :Lailai Zhu; Luca Brandt; Michael Graham; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hydrodynamic interaction; swimming microorganisms; capsule; Stokes flow; finite element method; boundary integral method; general geometry Ewald method; spectral element method; viscoelastic fluid; cellular deformation; flow cytometry; cell sorting; microrheology; Teknisk mekanik; Engineering Mechanics;

   Sammanfattning : In this thesis, simulations are performed to study the motion ofindividual cells in flow, focusing on the hydrodynamics of actively swimming cells likethe self-propelling microorganisms, and of passively advected objects like the red bloodcells. In particular, we develop numerical tools to address the locomotion ofmicroswimmers in viscoelastic fluids and complex geometries, as well as the motion ofdeformable capsules in micro-fluidic flows. LÄS MER

7. 5. Prediction of random vibration using spectral methods

   Författare :Fredrik Birgersson; KTH; []
   Nyckelord :Spectral finite element method; distributed excitation; turbulent boundary layer measurements; random vibration; spectral super element method; wave expansion difference scheme; fluid-structure interaction;

   Sammanfattning : Much of the vibration in fast moving vehicles is caused bydistributed random excitation, such as turbulent flow and roadroughness. Piping systems transporting fast flowing fluid isanother example, where distributed random excitation will causeunwanted vibration. LÄS MER