Sökning: "finite element method FEM"

Visar resultat 16 - 20 av 158 avhandlingar innehållade orden finite element method FEM.

1. 16. Historiska träbärverk : Strukturmekaniska metoder och visualisering

   Författare :Carl Thelin; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; FEM; Roof truss; Structural mechanics; Historic structure; Visualisation; Static behaviour; Static eigenvalue; Eigenmode; Finite Element Method;

   Sammanfattning : In designing and erecting buildings in historical times, creating the loadcarrying structure was perhaps the greatest challenge with which the architect and the builder were faced. We encounter structures in which there was a strive to reach vertical heights in the pillars and walls and to extend the horizontal span of the beams and vaults that were built. LÄS MER

3. 17. Two Problems in non-linear PDE’s with Phase Transitions

   Författare :Karl Jonsson; Henrik Shahgholian; Tomas Sjödin; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Conductivity jump; Free boundary problem; Quasilinear elliptic equation; Mathematical techniques; Nonlinear analysis; Free boundary; Free-boundary problems; Quasi-linear elliptic; Quasilinear elliptic equations; Hele-Shaw flow; non-local; implicit function theorem; Heterogeneous Multi Scale; HMM; Finite Element; FEM; FE; Mathematics; Matematik;

   Sammanfattning : This thesis is in the field of non-linear partial differential equations (PDE), focusing on problems which show some type of phase-transition. A single phase Hele-Shaw flow models a Newtoninan fluid which is being injected in the space between two narrowly separated parallel planes. LÄS MER

4. 18. Dimensioning Tools of MEA Actuator Systems, Including Modeling, Analysis and Technology Comparison

   Författare :Mohsen Torabzadeh-Tari; Göran Engdahl; Hans Bernhoff; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Dimensioning tools; MEA; More Electric Aircraft; EMA; Electro Mechanical Actuator; EM; Electrical Machine; Converter; Inverter; Finite Element Method; FEM; Electrical engineering; electronics and photonics; Elektroteknik; elektronik och fotonik;

   Sammanfattning : Aircraft design is an example of complex engineering where dimensioning tools can be valuable for the designers and decision makers in the early stage of the development process. These tools can be in form of a database over key numbers for different components or technologies. One of the critical parts of an aircraft is the actuator system. LÄS MER

5. 19. Optimization for scattering and radiation problems based on a stable FEM-FDTD hybrid method

   Författare :Tomas Halleröd; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; finite-difference time-domain; finite element method; array antennas; electric and magnetic losses; pattern synthesis; shape and material optimization; explicit-implicit time-stepping; scattering;

   Sammanfattning : In this thesis, a stable hybrid method combining the finite-elementmethod (FEM) and the finite-difference time-domain (FDTD) scheme forMaxwell's equations in two dimensions with both electric and magneticlosses is presented. It combines the flexibility of the FEM with theefficiency of the FDTD scheme. LÄS MER

7. 20. 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