Sökning: "in-cylinder flow structures"

Visar resultat 1 - 5 av 6 avhandlingar innehållade orden in-cylinder flow structures.

  1. 1. Creation and destruction of in-cylinder flows : Large eddy simulations of the intake and the compression strokes

    Författare :Martin Söder; Laszlo Fuchs; Angelo Onorati; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Swirl; Tumble; Compression; Engine; LES; CFD; engine turbulence; engine simulations; intake flow structures; Engineering Mechanics; Teknisk mekanik;

    Sammanfattning : The aim of this thesis is to increase engine efficiency by studying the flow structures created in an engine cylinder during the intake phase and the effect of the subsequent compression.The invention of the combustion engine has enabled three centuries of economic growth fueled by energy stored as hydrocarbons. LÄS MER

  3. 2. Investigation of Partially Premixed Combustion in an Optical Engine : In-Cylinder Flow and Combustion Characterization

    Författare :Slavey Tanov; Förbränningsmotorer; []
    Nyckelord :PPC; in-cylinder flow structures; Combustion diagnostics; Gasoline; Gasoline-Ethanol; Multiple Injection; Stratification Level;

    Sammanfattning : The diesel engine is one of the most economic power sources and is therefore used in a range of technical solutions. The low fuel consumption combined with high engine performance makes it attractive for transportation vehicles. LÄS MER

  4. 3. Large Eddy Simulation of Turbulent Flow and Combustion in HCCI Engines

    Författare :Rixin Yu; Strömningsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Turbulent combustion; Numerical methods.; LES; Temperature inhomogeneity; HCCI combustion; In-cylinder flow;

    Sammanfattning : This thesis deals with numerical simulations of the turbulent combustion process in Homogeneous Charge Compression Ignition (HCCI) engines. An accurate and computationally efficient Large Eddy Simulation (LES) model was developed and used throughout this thesis to investigate the development of in-cylinder turbulence, temperature stratification, onset of auto-ignition, and development of the reaction fronts. LÄS MER

  5. 4. Laser Diagnostics of HCCI and Partially Premixed Combustion

    Författare :Leif Hildingsson; Förbränningsmotorer; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; low temperature combustion; Motorer; Motors and propulsion systems; Teknik; Technological sciences; PIV; in-cylinder flow structures; hydroxyl; OH; partially-oxidized fuel; formaldehyde; HCOH; LIF; diesel combustion; partially premixed combustion; PPC; HCCI; framdrivningssystem;

    Sammanfattning : The work presented in this thesis deals with measuring in-cylinder combustion species and events using different laser-based diagnostic methods. A variety of engine operating modes, like HCCI and partially premixed diesel combustion, have been investigated. LÄS MER

  7. 5. Numerical Investigation of Internal Combustion Engine Related Flows

    Författare :Martin Söder; Laszlo Fuchs; Martin Tunér; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; CFD; LES; Engine; Intake; Compression;

    Sammanfattning : Internal combustion engines has been used for more than 100 years. The use of the abundant energy supply stored as hydrocarbon fueled unprecedented economic growth. The use of hydrocarbons increased the work output of human labor significantly, thus increasing the economy and prosperity. LÄS MER