Sökning: "kelvin-helmholtz"

Visar resultat 16 - 19 av 19 avhandlingar innehållade ordet kelvin-helmholtz.

  1. 16. Numerical and modelling aspects of large-eddy and hybrid simulations of turbulent flows

    Författare :Matteo Montecchia; Arne V. Johansson; Gert Brethouwer; Stefan Wallin; Dominic Von Terzi; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; turbulence; wall-bounded flows; large-eddy simulation; SGS modelling; OpenFOAM; hybrid RANS-LES; Engineering Mechanics; Teknisk mekanik;

    Sammanfattning : In this study, the explicit algebraic sub-grid scale (SGS) model (EAM) has been extensively validated in wall-resolved large-eddy simulations (LES) of wall-bounded turbulent flows at different Reynolds numbers and a wide range of resolutions. Compared to eddy-viscosity based models, the formulation of the EAM is more consistent with the physics and allows to accurately capture SGS anisotropy,which is relevant especially close to walls. LÄS MER

  3. 17. Numerical studies of receptivity, stability and transition of wing and turbine blade boundary layers

    Författare :Luca De Vincentiis; Ardeshir Hanifi; Dan S. Henningson; Stefania Cherubini; KTH; []
    Nyckelord :Teknisk mekanik; Engineering Mechanics;

    Sammanfattning : In the present thesis, receptivity, stability and laminar-turbulent transition of different boundary-layer flows are addressed and investigated by means of direct numerical simulations. In particular, flows over a wing and a low-pressure-turbine (LPT) blade have been the main focus. LÄS MER

  4. 18. Large Eddy Simulation of Turbulent Premixed and Partially Premixed Combustion

    Författare :Eric Baudoin; Strömningsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : In this thesis, a computational fluid dynamics (CFD) approach is used to study turbulent premixed and partially premixed combustion. The CFD approach is based on large eddy simulation (LES) in which the large-scale structures of the flow are resolved on a grid, leaving only the small-scale structures (subgrid scales) to be modeled. LÄS MER

  5. 19. Phenomenological and mechanistic modeling of melt-structure-water interactions in a light water reactor (LWR) severe accident

    Författare :Anh Bui Viet; KTH; []
    Nyckelord :;

    Sammanfattning : Severe accidents in light water reactors have been the fotalpoint of much research, performed in the last two decades,aimed at understarrding the inherent physical phenomena and toevaluate proposed accident management schemes for mitigatingthe consequences of such accidents. Severe accident progressionand consequences, av the reactor core overheats and melts, areintimately related to the interactions of the melt with coolant(water) and structures. LÄS MER