Sökning: "finite element FEM"

Visar resultat 21 - 25 av 201 avhandlingar innehållade orden finite element FEM.

1. 21. The interdependence of plastic behaviour and final properties of steel wire, analysed by the finite element method

   Författare :Henrik Överstam; Magnus Jarl; Sven-Erik Lundberg; Chunhui Luo; Örebro universitet; []
   Nyckelord :Technology; FEM; defects; steel wire; wire drawing; rolling; forging; Teknikvetenskap; TECHNOLOGY; TEKNIKVETENSKAP; Maskinteknik; Mechanical Engineering;

   Sammanfattning : The finite element method (FEM) has been used in order to study the interdependence of plastic behaviour and final properties in steel wire. Three processes metal forming have been studied: billet forging, wire rod rolling, and cold drawing. LÄS MER

3. 22. Inverse and optimization problems in electromagnetics -- a finite-element method perspective

   Författare :JOHAN WINGES; Chalmers tekniska högskola; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; microwave measurements; computational electromagnetics; finite element method; optimization; inductive power transfer; compressed sensing; wireless power; brick-tetrahedron hybrid; parameter estimation; inverse problems;

   Sammanfattning : In this thesis, a selection of inverse and optimization problems are studied where the finite element method (FEM) serves as a comprehensive tool to solve electromagnetic field problems that lack an analytic solution. The inverse problems are typically formulated in terms of an optimization problem where the misfit between a measurement and the corresponding result of a computational model is minimized. LÄS MER

4. 23. Stable FEM-FDTD Hybrid Method for Maxwell's Equations

   Författare :Thomas Rylander; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Finite Element Method; scattering; antennas; stability analysis; edge elements; Maxwell s equations; NASA almond; microwave circuits; mass lumping; proof of stability; explicit-implicit time-stepping; Finite-Differences Time-Domain;

   Sammanfattning : In this thesis edge elements are applied to solve several problems in computational electromagnetics. In particular, a hybrid scheme joining the Finite Element Method (FEM) and the Finite-Difference Time-Domain (FDTD) algorithm is developed, tested and exploited. LÄS MER

5. 24. On the Modelling of Fracture Using Strong Discontinuities

   Författare :Martin Fagerström; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fracture; strong discontinuity; material forces; finite deformations; FEM;

   Sammanfattning : The major concern of this work is the constitutive and numerical modelling of fracture,based on strong discontinuity formulations. More particularly, an extended finiteelement approach is used, where the total displacement is separated in two mutuallyindependent fields, representing the continuous and discontinuous displacement respectively. LÄS MER

7. 25. High Order Symmetric Finite Difference Schemes for the Acoustic Wave Equation

   Författare :Abraham Zemui; Bertil Gustafsson; Leif Abrahamsson; Per Weinerfelt; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; finite element method; mass lumping; high order; finite difference method; wave equation; Numerical Analysis; Numerisk analys;

   Sammanfattning : When someone speaks, or when a piano is played, sound waves are spread through the room. Physically the propagation of sound is governed by the acoustic wave equation. This thesis deals with the problem of finding solutions to this equation by numerical methods. LÄS MER