Sökning: "fysiska flöden"

Visar resultat 1 - 5 av 19 avhandlingar innehållade orden fysiska flöden.

  1. 1. Homogeneous Ignition - Chemical Kinetic Studies for IC-Engine Applications

    Författare :Per Amnéus; Förbränningsfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Skeletal mechanism; Mechanism reduction; n-heptane; iso-octane; formaldehyde; methane; Motors and propulsion systems; Motorer; framdrivningssystem; Physics; Fysik; Detailed chemistry; Kinetic calculations; Engine knock; Homogeneous charge compression ignition; HCCI; Fysicumarkivet A:2002:Amnéus;

    Sammanfattning : Calculations on a Homogeneous Charge Compression Ignition (HCCI) engine have been performed. Zero-dimensional models were used. The simplest model compressed the gas to auto-ignition, using temperature and pressure at a certain crank angle position obtained from engine experiments. LÄS MER

  3. 2. Evaluating methods in source apportionment of the carbonaceous aerosol

    Författare :Johan Martinsson; Kärnfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Atmosfäriska partiklar (aerosoler) finns överallt i jordens atmosfär. Masskoncentrationen av dessa varierar kraftigt beroende på i vilken miljö man mäter. I stadsluft kan man uppmäta tiotals mikrogram per kubikmeter medan man i arktiska områden uppmäter nanogram per kubikmeter. LÄS MER

  4. 3. Development and application of photofragmentation laser-induced fluorescence for visualization of hydrogen peroxides

    Författare :Olof Johansson; Förbränningsfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Flame diagnostics; Fluorescence lifetime imaging; Hydrogen peroxide; Laser diagnostics; Laser-induced fluorescence; Photofragmentation;

    Sammanfattning : The work presented in this thesis is mainly motivated by the need for an optical diagnostic technique which can be used to visualize hydrogen peroxide (H2O2) in its gas phase. Due to the lack of bound electronic states, H2O2 cannot be detected using laser-induced fluorescence based on electronic excitation. LÄS MER

  5. 4. Laser Diagnostics Applied to Lean Premixed Swirling Flames - Simultaneous Flow Field and Scalar Measurements

    Författare :Per Petersson; Förbränningsfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Volumetric Velocimetry; Low-swirl Flames; Premixed Flames; Turbulent Combustion; Particle Image Velocimetry; Laser Diagnostics; A.2014:Petersson; Combustion Diagnostics;

    Sammanfattning : The work reported here includes experimental studies of lean premixed swirling flames. Various laser-based optical diagnostic techniques were used to collect information under different operational conditions. Combined flow- and scalar field measurements were performed at high repetition rates for detailed studies of the turbulent flames. LÄS MER

  7. 5. Development of Laser-Spectroscopic Techniques for New Detection Schemes in Combustion Diagnostics

    Författare :Johan Zetterberg; Förbränningsfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Laser-Spectroscopy; Laser Combustion Diagnostics; Rayleigh scattering; FRS; LIF; Polarization Spectroscopy; PS; IRPS;

    Sammanfattning : The thesis work, aimed at the development of laser-spectroscopic detection schemes, consists of three parts, concerned with the development and application of different techniques. The development of UV filtered Rayleigh scattering (FRS) for thermometry and fuel/air ratio measurements, using a frequency tripled, single-longitudinal-mode alexandrite laser at ~254 nm together with an isotopically enhanced mercury filter, is examined first. LÄS MER