Sökning: "DNS channel flow"

Visar resultat 1 - 5 av 17 avhandlingar innehållade orden DNS channel flow.

  1. 1. DNS and LES of Turbulent Natural Convection Boundary Layer

    Författare :Darioush Gohari Barhaghi; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; DNS; free convection; LES; natural convection boundary layer; vertical cylinder;

    Sammanfattning : Turbulent natural convection boundary layers possess some special characteristicscompared to the other boundary layers.In order to study this kind of boundary layer, two powerful numerical methods,Direct Numerical Simulation or DNS and Large Eddy Simulation or LES,are used. LÄS MER

  3. 2. A Study of Turbulent Natural Convection Boundary Layers Using Large-Eddy Simulation

    Författare :Darioush Gohari Barhaghi; Chalmers tekniska högskola; []
    Nyckelord :natural convection boundary layer; DNS; LES; radiation heat transfer; free convection; cavity; vertical cylinder;

    Sammanfattning : The structure of turbulent natural convection boundary layers in differentgeometries and the effect of the buoyancy on a mixed convection boundarylayer are investigated. These geometries comprise a vertical finitecylinder, a vertical infinite channel, a cavity and a vertical finite channel. LÄS MER

  4. 3. Theoretical and numerical studies of sound propagation in low-Mach-number duct flows

    Författare :Chenyang Weng; Mats Åbom; Susann Boij; Ardeshir Hanifi; Anurag Agarwal; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Aeroacoustics; Acoustic wave absorption; Acoustic wave propagation; Boundary layer turbulence; DNS; Engineering Mechanics; Teknisk mekanik;

    Sammanfattning : When sound waves propagate in a duct in the presence of turbulent flow, turbulent mixing can cause attenuation of the sound waves extra to that caused by the viscothermal effects. Experiments show that compared to the viscothermal effects, this turbulent absorption becomes the dominant contribution to the sound attenuation at sufficiently low frequencies. LÄS MER

  5. 4. Laminar and turbulent particle laden flows : a numerical and experimental study

    Författare :Seyed Hamid Tabaeikazerooni; Luca Brandt; Jeanette Hussong; Raffaella Ocone; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Suspension flow; inertial effect; turbulent duct flow; finite-size particles; Immersed Boundary Method IBM ; Astigmatism Particle Tracking Velocimetry APTV ; Engineering Mechanics; Teknisk mekanik;

    Sammanfattning : Particle laden flows are widespread in nature and in industrial applications. Dust storms, geophysical flows, pharmaceutical processes, fluidized beds and blood flow are only a few examples. Both global and local properties of a particle laden flow may alter significantly in comparison to the corresponding single phase flow. LÄS MER

  7. 5. Towards Improved Scale-Resolving Modeling and Simulations of Turbulent Flows

    Författare :Magnus Carlsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hybrid RANS-LES; Numerical methods; Synthetic Turbulence; Compressible flow; Scale-resolving simu- lation; High-order gradient reconstruction; Turbulence modelling;

    Sammanfattning : Scale-resolving simulations are viewed as powerful means for predicting complex turbulentflows, as often encountered in aeronautical applications. However, since turbulent scalesspan over a considerable range from the smallest Kolmogorov scales to the largest ofequivalence to configuration size, scale-resolving computations are often demandingon computational resources and, furthermore, on the underlying numerical methodsused in the simulations. LÄS MER