Sökning: "length-scale"

Visar resultat 16 - 20 av 138 avhandlingar innehållade ordet length-scale.

  1. 16. Numerical Simulation of Some Heat Transfer and Fluid Flow Phenomena for Gas Turbine Blades and a Transonic Turbine Stage

    Författare :Fadil Mumic; Värmeöverföring; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fluiddynamik; plasma; Thermal engineering; applied thermodynamics; plasmas; Gaser; fluid dynamics; Gases; transonic; numerical; heat transfer coefficient; shroud surface; squealer blade tip; flat blade tip; leakage flow; Termisk teknik; termodynamik; turbulence modeling;

    Sammanfattning : With the attempts to achieve higher thermal efficiency, turbine blades are exposed to very high temperature gases and may undergo severe thermal stress and fatigue. Thus, in order to develop optimal cooling strategies and reduce the heat transfer it is important to obtain a good understanding of both the complex flow field and the heat transfer characteristics in turbine rotor/stator hot-gas passages. LÄS MER

  2. 17. Numerical Modelling of Diesel Spray Injection and Turbulence Interaction

    Författare :Fabian Kärrholm Peng; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Computational Fluid Dynamics; Spray; Cavitation; Cavitation; Turbulence Model; AtomizationTurbulence Model; Diesel; Atomization;

    Sammanfattning : It has been established by many authors that numerical simulations ofDiesel sprays, using a Lagrangian description for the liquid phase,are particularly sensitive to the scale of the computational cellscompromising the mesh. There have been many suggestions regardingmeans to reduce the dependency on the mesh by improving the componentsubmodels, but few have addressed the gas phase turbulence modelling. LÄS MER

  3. 18. Simulations of Transport Phenomena and Porous Structures Using Dissipative Particle Dynamics

    Författare :Erik Johansson; Värmeöverföring; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : The topic of this work is simulations of porous materials and transport phenomena at a mesoscopic length scale, i.e., a length scale larger than an individual atom but smaller than the continuum. The porous material studied is a membrane used in fuel cells. LÄS MER

  4. 19. Modelling and simulation of plastic deformation on small scales : interface conditions and size effects of thin films

    Författare :Per Fredriksson; Peter Gudmundson; Christian Niordson; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Strain gradient plasticity; Size effects; Thin films; Interface; Finite element method; Dislocations; Constitutive behaviour; Hardening behaviour; Indentation; Contact mechanics; Metal matrix composites; Engineering mechanics; Teknisk mekanik;

    Sammanfattning : Contrary to elastic deformation, plastic deformation of crystalline materials, such as metals, is size-dependent. Most commonly, this phenomenon is present but unnoticed, such as the effect of microstructural length scales. LÄS MER

  5. 20. Structure evolution of spin-coated phase separated EC/HPC films

    Författare :Pierre Carmona; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; spin-coating; controlled drug release; porous film; drug delivery; confocal laser scanning microscope; kinetics; phase separation mechanisms; cellulose; biopolymer; phase separation;

    Sammanfattning : Porous phase-separated films made of ethylcellulose (EC) and hydroxypropylcellulose (HPC) are commonly used for controlled drug release. The structure of these thin films is controlling the drug transport from the core to the surrounding liquid in the stomach or intestine. However, detailed understanding of the structure evolution is lacking. LÄS MER