Search for dissertations about: "DFWM"

Showing result 1 - 5 of 8 swedish dissertations containing the word DFWM.

  2. 1. Resonant Laser Techniques for Combustion and Flow Diagnostics

    Author : Rolf Fritzon; Förbränningsfysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; species; laser diagnostic techniques; temperature imaging; polarization spectroscopy; stimulated emission; DFWM; Fysik; Physics; turbulent mixing; LIF; Fysicumarkivet A:1998:Fritzon;

    Abstract : This thesis presents results from two areas of research. Firstly, the resonant coherent laser techniques polarization spectroscopy (PS), degenerate four-wave mixing (DFWM) and stimulated emission (SE) have been developed in the general field of combustion diagnostics. READ MORE

  4. 2. Laser-Based Techniques for Combustion Diagnostics

    Author : Nikola Georgiev; Förbränningsfysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Physics; LIF; Laser-based diagnostic techniques; PS; DFWM; Fysik; Fysicumarkivet A:1997:Georgiev;

    Abstract : Two-photon-induced Degenerate Four-Wave Mixing, DFWM, was applied for the first time to the detection of CO, and NH3 molecules. Measurements were performed in a cell, and in atmospheric-pressure flames. In the cell measurements, the signal dependence on the pressure and on the laser beam intensity was studied. READ MORE

  5. 3. Development and Application of Non-linear Mid-infrared Laser Spectroscopy for Combustion Diagnostics

    Author : Zhiwei Sun; Förbränningsfysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Degenerate four-wave mixing; Polarization spectroscopy; Mid-infrared; Non-linear laser spectroscopy; Laser diagnostics; Combustion; Flame; HITRAN; Concentration; Temperature; Fysicumarkivet A:2012:Sun;

    Abstract : The work reported in this thesis involved the development and application of two novel infrared non-linear laser techniques, namely mid-infrared polarization spectroscopy (IRPS) and mid-infrared degenerate four-wave mixing (IR-DFWM) to combustion diagnostics. These two techniques meet the needs of species concentration detection in combustion environments, especially for those species lacking accessible electronic (one-photon) transitions in the ultraviolet (UV) or visible spectral region. READ MORE

  6. 4. Infrared Laser-Induced Grating Techniques for Diagnostics in Reactive Flows

    Author : Dina Hot; Förbränningsfysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Laser diagnostics; infrared; laser-induced grating spectroscopy; degenerate four-wave mixing; flames; temperature; concentration; Fysicumarkivet A:2020:Hot;

    Abstract : AbstractThe work presented in this thesis is mainly focused on the development andapplication of infrared laser-induced grating techniques in order to measure the gasphase temperature and species concentrations in reactive flows. The two techniquesused for this purpose are laser-induced grating spectroscopy (LIGS) and degeneratefour-wave mixing (DFWM). READ MORE

  7. 5. Upconversion Detection for Improved Nonlinear Mid-infrared Spectroscopy in Flames

    Author : Rasmus Lyngbye Pedersen; Förbränningsfysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; infrared; upconversion; degenerate four wave mixing; hydrogen cyanide; polarisation spectroscopy;

    Abstract : This thesis deals with the addition of upconversion detection to non-linear mid-infrared laser spectroscopy techniques. The techniques investigated here are degenerate four wave mixing (DFWM) and infrared polarization spectroscopy (IRPS). READ MORE