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Visar resultat 1 - 5 av 36 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Numerical Simulation of High Reynolds Number Wall Bounded Flow

    Författare :Tobias Persson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; subgrid model; DES; high; validation; LES; numerical simulation; near-wall;

    Sammanfattning : In this thesis, four different numerical methods are used for predictions of high Reynoldsnumber (Re), wall bounded flows; Large Eddy Simulation (LES) with two different subgrid(turbulence) models, the One Equation Eddy Viscosity model (OEEVM) and the MixedModel (MM), Monotone Integrated LES (MILES), Detached Eddy Simulation (DES) andReynolds Averaged Navier Stokes (RANS). The LES calculations are combined with a wallmodel based on the law-of-the-wall and in DES a hybrid RANS/LES method is used forhandling the near wall region. LÄS MER

  3. 2. Experimental studies of the plane turbulent wall jet

    Författare :Jan Eriksson; KTH; []
    Nyckelord :Plane turbulent wall jet; turbulence measurements; LDV; near-wall region;

    Sammanfattning : .... LÄS MER

  4. 3. Turbulence Modelling of Flows Related to Wall-Cooling Applications

    Författare :Stefan Jansson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; low-Reynolds number models; second-order-moment closures; turbulent heat transfer; two-equation models; film-cooling; near-wall models; turbulence modelling;

    Sammanfattning : Engineering flows are generally characterised by complex strain field and turbulence structure arising from a combination of shear, curvature, separation and recirculation etc. Under such flow conditions, transport by turbulent velocity fluctuations can make a significant contribution to the transport of momentum, heat and mass. LÄS MER

  5. 4. Simulations of turbulent boundary layers with suction and pressure gradients

    Författare :Alexandra Bobke; Philipp Schlatter; Ramis Örlü; Ayse Gul Gungor; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; boundary layers; near-wall turbulence; history effects; asymptotic suction boundary layers; large-eddy simulation;

    Sammanfattning : The focus of the present licentiate thesis is on the effect of suction and pressure gradients on turbulent boundary-layer flows, which are investigated separately through performing numerical simulations.The first part aims at assessing history and development effects on adverse pressure-gradient (APG) turbulent boundary layers (TBL). LÄS MER

  7. 5. Experimental studies in jet flows and zero pressure-gradient turbulent boundary layers

    Författare :Ramis Örlü; P. Henrik Alfredsson; Tim B. Nickels; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Axisymmetric jet; swirling jet; coaxial jet; heated jet; zero pressuregradient turbulent boundary layer; wall-bounded turbulent flows; overlap region; passive scalar mixing; hot-wire anemometry; spatial resolution.; Fluid mechanics; Strömningsmekanik;

    Sammanfattning : This thesis deals with the description and development of two classical turbulent shear flows, namely free jet and flat plate turbulent boundary layer flows. In both cases new experimental data has been obtained and in the latter case comparisons are also made with data obtained from data bases, both of experimental and numerical origin. LÄS MER