Browsing Theses--ERC by Issue Date
Now showing items 1-20 of 44
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Wavelength-Agile Rayleigh Scattering by use of an Atomic Vapor Cell
(2005)A wavelength-agile technique using an atomic vapor cell is developed and applied to the measurement of Rayleigh scattering. The atomic vapor cell displays a steep change in refractive index as a function of wavelength, ... -
Application of Supercontinuum Generation to Practical Absorption Spectroscopy
(2005)Supercontinuum light generation was used as a means to generate broadband light for spectroscopic measurements. The generated broadband light was used to measure carbon monoxide (CO) absorption in a sealed laboratory ... -
Development of a Spatially Resolved Optical Technique to Measure Temperature using Two-Photon Absorption of Xenon
(2005)A new spatially resolved optical technique to measure temperature was developed using two-photon absorption of xenon. This experiment excited the 256 nm two-photon transition of xenon by focusing the excitation source ... -
High Spectral Resolution Emission Thermometry for Combustion Applications
(2005)Several spectroscopic emission methods were investigated for the determination of combustion gas temperature. Spectroscopic simulations based on the HITRAN database were performed to aid in sensor design and data ... -
INSTRUMENTATION FOR ABSORPTION
(2009-06-19)In order to measure ultraviolet spectra, an instrumentation method must be carefully selected. The first consideration is whether to use a hyperspectral source in combination with a singleelement photodiode or a broadband ... -
Strategies for Optical Measurements in Rocket Plumes
(2009-06-19)An ideal rocket engine sensing system might probe several key elements of the rocket engine including: the fuel and oxidizer supply for mass flow rate and impurities, the combustion chamber for pressure and mole fraction ... -
HIGH-SPEED, CONTINUOUS MONITORING OF LIQUID SPRAYS BY MULTI-WAVELENGTH ABSORPTION SPECTROSCOPY
(2009-06-24)A fiber-optic array was created by arranging four Corning lensed fibers in a parallel, horizontal plane. It has been shown that through the use of multiwavelength spectroscopy, this fiber array is capable of probing a ... -
Water Vapor Absorption Thermometry for Practical Combustion Applications
(2009-06-24)Thermometry in combustion applications by means of laser absorption spectroscopy is a well established diagnostic. The experimental simplicity and wealth of knowledge that can be readily gained from an absorption spectrum ... -
FUNDAMENTALS OF TRANSIENT THERMAL-LIGHT ABSORPTION SPECTROSCOPY AND APPLICATION TO OPTICAL SENSING IN HCCI ENGINES
(2009-06-24)A set of equations is developed for evaluating absorption spectroscopy based on thermal emitters such as lamps. The noise sources considered are photon (shot) noise and beating (wave interference) noise; signal-to-noise ... -
CONTINUOUS-WAVE COMB FOURIER TRANSFORM SPECTROSCOPY
(2009-06-24)Due to its versatility, Fourier-transform spectroscopy (FTS) has found wide-spread application in research and development, monitoring of industrial processes, forensics, etc1; its uses continue to expand2. Despite decades ... -
HYPERSPECTRAL LASERS FOR SPECTROSCOPIC MEASUREMENTS IN THE NEAR-INFRARED
(2009-06-24)This project develops hyperspectral lasers that are built using fiber-optic cavities and broadband semiconductor gain media. These sources are custom designed for high-speed (typically 30 kHz) spectroscopic sensing ... -
WAVELENGTH-AGILE ABSORPTION SPECTROSCOPY FOR MEASURING TEMPERATURE AND H2O MOLE FRACTION IN HARSH ENVIRONMENTS
(2009-06-24)This project develops the necessary tools and methods to measure H2O absorption spectra in harsh environments, and calculate temperature and mole fraction from the measured spectra. Various wavelength-agile sources are ... -
WAVELENGTH-MULTIPLEXED ABSORPTION SPECTROSCOPY APPLIED TO AN HCCI ENGINE
(2009-06-24)A new optical technique to measure real time in-cylinder temperature was developed using fiber Bragg gratings. For this aim, a time multiplexing and a frequency multiplexing sensor system were designed and developed. ... -
NOISE-FREE INCORPORATION OF MULTIMODE FIBERS INTO ABSORPTION SPECTROSCOPY EXPERIMENTS
(2009-06-24)This project develops and evaluates alternative methods to the traditional way of detecting light transmitted through optical fibers in spectroscopy experiments. The main motivation behind this work is to develop an ... -
EXPERIMENTAL INVESTIGATION OF BULK FLAME QUENCHING IN A DIRECT-INJECTION SPARK IGNITION ENGINE
(2009-07-08)The following thesis describes planar laser-induced fluorescence (PLIF) experiments that investigate bulk flame quenching in the lean periphery of a stratified fuel cloud during light-load operation of a direct-injection ... -
QUANTITATIVE 2-D FUEL VAPOR CONCENTRATION MEASUREMENTS IN AN EVAPORATING DIESEL SPRAY USING THE EXCIPLEX FLUORESCENCE METHOD
(2009-07-08)To experimentally investigate evaporating sprays under conditions experienced in high speed direct-injection (HSDI) diesel engines, the exciplex (excited state complex) laser-induced fluorescence technique and high-speed ... -
Spray Mixing in Engines
(2009-07-08)The mixing of a fuel spray in an optically accessible direct-injection spark-ignition engine was investigated to yield both comparative conclusions between different engine characteristics and fundamental observations of ... -
Investigation of Flame-Front Equivalence Ratio during Stratified Engine Combustion
(2009-07-08)Stratified engine combustion was investigated using simultaneous imaging of the fuel distribution and flame front in an optically accessible direct-injection spark-ignition engine. Planar laser-induced fluorescence of ... -
PISTON HEAT TRANSFER IN AN AIR-COOLED ENGINE
(2009-07-08)Thermal energy flow within the piston of an air cooled engine was investigated by measuring the heat flux in the engine cylinder liner in the region of travel of the piston rings. Engine sump oil temperature and oil ... -
SCAVENGING MEASUREMENTS IN A DIRECT-INJECTION TWO-STROKE ENGINE
(2009-07-08)The scavenging process in a direct-injection two-stroke research engine was examined. A physical model was developed to characterize scavenging based on known quantities. An electromagnetic valve was used to sample ...