Sökning: "Multiscale"

Visar resultat 16 - 20 av 182 avhandlingar innehållade ordet Multiscale.

1. 16. Computational Multiscale Modeling of Pearlitic Steel

   Författare :Erik Lindfeldt; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Multiscale modeling; homogenization; pearlite; crystal plasticity;

   Sammanfattning : The objective of this thesis is to investigate the possibilities to describe the mechanical behaviorof a pearlitic steel by using computational homogenization, or multiscale modeling. The proposed model contains three scales: the engineering macroscale, the mesoscale representing the colonies of the pearlite and the microscale containing the individual cementite lamellae and the ferrite matrix. LÄS MER

3. 17. On multiscale modeling of pearlitic steel

   Författare :Erik Lindfeldt; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; cementite; crystal plasticity; Pearlite; multiscale modeling; computational homogenization; digital image correlation; ferrite; in-situ SEM;

   Sammanfattning : By studying pearlitic steels using a scanning electron microscope it can be observed that pearlite is a two-phase material with cementite lamellae embedded in a matrix of ferrite. The cementite is commonly described as being stiff and brittle in comparison to the ferrite which is considered to have a soft and ductile mechanical behavior. LÄS MER

4. 18. Numerical Analysis of Evolution Problems in Multiphysics

   Författare :Anna Persson; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; regularity; generalized finite element; localized orthogonal decomposition; multiscale; finite element method; Thermoelasticity; Riccati equations; thermistor; linear elasticity; Joule heating; parabolic equations; Regularity; generalized finite element; localized orthogonal decomposition; multiscale finite element method; Thermoelasticity; Riccati equations; thermistor; linear elasticity; Joule heating; parabolic equations;

   Sammanfattning : In this thesis we study numerical methods for evolution problems in multiphysics. The term multiphysics is commonly used to describe physical phenomena that involve several interacting models. Typically, such problems result in coupled systems of partial differential equations. LÄS MER

5. 19. Multiscale Modeling of Interfaces

   Författare :Sven Johansson; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; misfit; Peierls-Nabarro model; semicoherent interfaces; interfaces; cemented carbides; grain boundaries; microstructure; VN precipitates; density-functional theory;

   Sammanfattning : Understanding strength and stability of interfaces between dissimilar materials or phases is a highly active field of contemporary materials research. Knowledge of interface structure and energetics is important for modeling of complex materials both on a mechanical and thermodynamical level as well as for many functional properties. LÄS MER

7. 20. Multiscale methods for simulation of paper making

   Författare :Gustav Kettil; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Paper making; Numerical upscaling; Lay down simulations; Virtual paper sheets; Fiber network model; Forming fabric flow; Fiber suspension flow; Fiber-fiber interaction; Multiscale methods; Fluid structure interaction;

   Sammanfattning : In this work, multiscale methods for simulation of paper making are developed. The emphasis is on simulation of the paper forming process and simulation of the mechanical properties of paper sheets. To simulate paper forming, a novel fiber-fiber interaction method is proposed. LÄS MER