Sökning: "large-eddy simulation LES"

Visar resultat 11 - 15 av 127 avhandlingar innehållade orden large-eddy simulation LES.

  1. 11. Large eddy simulation using linear eddy sub-grid mixing modeling

    Författare :Salman Arshad; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Linear Eddy Model; Large Eddy Simulation; LES-LEM; Splicing;

    Sammanfattning : As emissions regulations are getting stricter and efficiency requirements of engines are increasing, different concepts to improve combustion are beinginvestigated. For example lean stratified premixed combustion, homogeneous charge compression ignition(HCCI), use of more exhaust gas recirculation (EGR) to reduce NOx etc. LÄS MER

  2. 12. Large Eddy Simulations of Separated Compressible Flows around Wing Sections

    Författare :Jörgen Held; Strömningsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; turbulence; subgrid-scale; shock-boundary layer interaction; wing section; transonic; subsonic; compressible; separated; Large eddy simulation; LES; PVM; Mechanical engineering; hydraulics; vacuum technology; vibration and acoustic engineering; Maskinteknik; hydraulik; vakuumteknik; vibrationer; akustik;

    Sammanfattning : This thesis concerns numerical calculations of compressible separated flows, with and without shocks, around wing sections using Large Eddy Simulations (LES). The considered geometries are the NACA 0012 wing section and the ONERA AT15A wing section. LÄS MER

  3. 13. A Study of Mach 0.75 Jets and Their Radiated Sound Using Large-Eddy Simulation

    Författare :Niklas Andersson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Jet noise; CAA; LES; Large Eddy Simulation; Computational Aero-Acoustics;

    Sammanfattning : Large-Eddy Simulations (LES) of a compressible nozzle/jet configuration have been carried out. Two jets were simulated, an isothermal jet and a jet with a higher temperature than the surrounding air. The Mach number was in both cases 0.75 and the jet Reynolds number was 50,000. LÄS MER

  4. 14. Large Eddy Simulation of the Flow around a High-Lift Airfoil

    Författare :Simon Dahlström; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; mildly separation; hybrid RANS LES; incompressible finite volume; airfoil; transition; large Eddy simulation; approximate wall boundary condition;

    Sammanfattning : The work presented in this thesis concerns the efforts of conducting a Large Eddy Simulation (LES) around an airfoil. The airfoil is close to stall, near maximum lift and the Reynolds number is high. In the flow a transitional separation bubble is present. LÄS MER

  5. 15. Large eddy simulation of cavitating and non-cavitating flow

    Författare :Tobias Huuva; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; high Reynolds number; Cavitation; turbulence; RANS; hydrodynamics; numerical simulation; modelling; DES; LES;

    Sammanfattning : Most marine configurations are subject to a number of complex and important hydrodynamic phenomena affecting the overall performance of the vessel, both regarding resistance and propulsive efficiency. In this thesis, the possibility of numerically simulating some of these phenomena is investigated. LÄS MER