Sökning: "transitional"

Visar resultat 6 - 10 av 215 avhandlingar innehållade ordet transitional.

  1. 6. Topology optimization of transitional flows

    Författare :Harrison Nobis; Dan Henningson; Philipp Schlatter; Paolo Luchini; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Direct Numerical Simulation; Topology Optimization; Laminar– Turbulent Transition; Spectral Element Method; Direkt numerisk simulering; topologioptimering; laminär–turbulent omslag; spektralelementmetod; Teknisk mekanik; Engineering Mechanics;

    Sammanfattning : This thesis is concerned with the application of topology optimization in thedesign of structures that control fluids. A framework is developed in the high-order Spectral Element Method (SEM) code Nek5000, extending Nek5000 fromits original capabilities, performing Direct Numerical Simulations (DNS), toperforming density-based topology optimization. LÄS MER

  3. 7. Infant mortality in transitional Nicaragua

    Författare :Rodolfo Peña; Umeå universitet; []
    Nyckelord :;

    Sammanfattning : .... LÄS MER

  4. 8. Transitional flow in ordered porous media

    Författare :Tobias Forslund; Staffan Lundström; Sofia Larsson; Gunnar Hellström; Krishna Pillai; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Porous media; Lattice Boltzmann Method; GPU Programming; Tomographic PIV; Laser Doppler Velocimetry; Strömningslära; Fluid Mechanics;

    Sammanfattning : Porous media, here defined as any permeable structure allowing a fluid to flow through, are relevant to a multitude of engineering applications and natural processes. The observed macroscopic properties of the porous media such as mixing, heat transfer and apparent permeability are properties which are affected by the flow and especially the type of flow, or flow region. LÄS MER

  5. 9. Transitional and turbulent fibre suspension flows

    Författare :Mathias Kvick; Fredrik Lundell; Daniel Söderberg; Lisa Prahl Wittberg; Björn Hof; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fluid mechanics; fibre suspension; turbulence; laminar-turbulent transition; image analysis; hydrodynamic stability; cellulose nanofibrils.; Engineering Mechanics; Teknisk mekanik;

    Sammanfattning : In this thesis the orientation of macro-sized fibres in turbulent flows is studied, as well as the effect of nano-sized fibrils on hydrodynamic stability. The focus lies on enabling processes for new materials where cellulose is the main constituent. LÄS MER

  7. 10. Modelling of stably-stratified, convective and transitional atmospheric boundary layers using the explicit algebraic Reynolds-stress model

    Författare :Velibor Zeli; Gert Brethouwer; Arne V. Johansson; Stefan Wallin; Bert Holtslag; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; atmospheric turbulence; convective atmosphere; Reynolds-stress model; stably-stratified atmosphere; transitional atmosphere; Engineering Mechanics; Teknisk mekanik;

    Sammanfattning : The atmospheric boundary layer (ABL) is in continuous turbulent motion. The heating and cooling of the Earth’s surface drives mechanic and thermodynamic processes in the ABL through enhancing and damping of atmospheric turbulence. The surface forcing has a profound effect on the diurnal cycle of temperature,wind and related variables in the ABL. LÄS MER