Sökning: "High Reynolds-number turbulent flow"

Visar resultat 1 - 5 av 52 avhandlingar innehållade orden High Reynolds-number turbulent flow.

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. On Turbulent Wall Jets

   Författare :Hans Abrahamsson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; self-preservation; similarity theory; scaling laws; local flow reversals; high turbulence levels; turbulent kinetic energy budget; two-dimensional; turbulent; hot-wire anemometry; wall jet; three-dimensional; pulsed hot-wire anemometry;

   Sammanfattning : An experimental investigation of the two- and three-dimensional turbulent wall jets has been conducted. The measurements have been performed using different hot-wire techniques in large scale wall jet facilities, and the measurements were focused on the fully-developed region of the flow. LÄS MER

4. 3. Modelling and control of turbulent and transitional flows

   Författare :Pierluigi Morra; Dan S. Henningson; Ardeshir Hanifi; André V. G. Cavalieri; Shervin Bagheri; Aimee S. Morgans; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; reduced order modeling; flow control; resolvent analysis; transi- tional boundary layer; turbulent boundary layer; drag reduction; high-fidelity wall-turbulence modelling; modellreduktion; strömningskontroll; resolvent analys; laminär- turbulent omslag; turbulent gränsskikt; motståndsminskning; väggturbulens modellering; Engineering Mechanics; Teknisk mekanik;

   Sammanfattning : The dynamics of fluid motion can accurately be described by the Navier– Stokes equations. Manipulating these equations to reduce their complexity but preserving their main characteristics has always been a key research activity in the field of fluid mechanics. LÄS MER

5. 4. Non-Spherical Particle Interaction in Duct and Jet Flow

   Författare :Ammar Hazim; Matthias Mandø; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Solid-gas flow; turbulence modulation; duct flow; coaxial jets flow; swirl jet flow; active flow control; synthetics jet; biomass powder; non-spherical particles; PIV measurement; Strömningslära; Fluid Mechanics;

   Sammanfattning : Wood waste is the most popular biomass recourse for many nations. Burned wood can, direct or indirect, release one of the greenhouse gases, carbon dioxide. The process can still be seen as a renewable source of energy since replanting of the trees and crops are consuming nearly the same amount of carbon dioxide through photosynthesis. LÄS MER

7. 5. 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