Sökning: "Numerical Flow Simulation"

Visar resultat 1 - 5 av 390 avhandlingar innehållade orden Numerical Flow Simulation.

  1. 1. Numerical Studies of Flow and AssociatedLosses in the Exhaust Port of a Diesel Engine

    Författare :Yue Wang; Laszlo Fuchs; Mihai Mihaescu; Angelo Onorati; KTH; []
    Nyckelord :Internal Combustion Engine; Exhaust flow; Exhaust Valve; Exhaust Port; Large Eddy Simulation; Valve and Piston Motion; Total Pressure Losses; Energy Losses; Discharge coefficient; Flow Losses; Flow structures; Air Flow Bench; Engine-like Conditions; SRA - Energy; SRA - Energi;

    Sammanfattning : In the last decades, the focus of internal combustion engine development has moved towards more efficient and less pollutant engines. In a Diesel engine, approximately 30-40% of the energy provided by combustion is lost through the exhaust gases. The exhaust gases are hot and therefore rich of energy. LÄS MER

  3. 2. Direct numerical simulation of turbulent flow in plane and cylindrical geometries

    Författare :Jukka Komminaho; KTH; []
    Nyckelord :turbulence; plane Couette flow; pipe flow; laminar-turbulent transition; direct numerical simulation; spectral methods;

    Sammanfattning : This thesis deals with numerical simulation of turbulentflows in geometrically simple cases. Both plane and cylindricalgeometries are used. The simplicity of the geometry allows theuse of spectral methods which yield a very high accuracy usingrelatively few grid points. A spectral method for planegeometries is implemented on a parallel computer. LÄS MER

  4. 3. 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

  5. 4. Modelling of Bingham Suspensional Flow : Influence of Viscosity and Particle Properties Applicable to Cementitious Materials

    Författare :Annika Gram; Björn Lagerblad; Ulrich Diederichs; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Self-Compacting Concrete; SCC; Fresh concrete flow; Numerical simulation; Viscosity; Open channel flow;

    Sammanfattning : Simulation of fresh concrete flow has spurged with the advent of Self-Compacting Concrete, SCC. The fresh concrete rheology must be compatible with the reinforced formwork geometry to ensure complete and reliable form filling with smooth concrete surfaces. LÄS MER

  7. 5. Unsteady Numerical Simulations of Flow around Heavy Vehicles, Trains and Passenger Cars

    Författare :Jan Östh; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Large Eddy Simulation; fluid dynamics; bluff body flows; flow structures; vehicle aerodynamics; flow control; flow physics; truck aerodynamics; train aerodynamics; car aerodynamics;

    Sammanfattning : In this thesis several simulations have been carried out aimed at improving the knowledgeof vehicle aerodynamics and improving the flow around vehicles with respect to theaerodynamic drag. Four flows around different simplified vehicles have been considered. LÄS MER