Download or read book In situ Measurement of Line of sight Soot Volume Fraction by Laser Light Extinction in a Combustion Wind Tunnel written by Steven George Hall and published by . This book was released on 1992 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Soot Volume Fraction and Temperature Measurement in a Slot Burner Utilizing Laser Extinction and Emission written by Jimmy Jean Daghlian and published by . This book was released on 2002 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sensitivity of Flame Structure and Particulate Matter Emissions to the Operating Configurations of a Combustion Wind Tunnel written by and published by . This book was released on 1993 with total page 94 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Soot Volume Fraction Imaging written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-11 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: A new technique is described for the full-field determination of soot volume fractions via laser extinction measurements. This technique differs from previously reported point-wise methods in that a two-dimensional array (i.e., image) of data is acquired simultaneously. In this fashion, the net data rate is increased, allowing the study of time-dependent phenomena and the investigation of spatial and temporal correlations. A telecentric imaging configuration is employed to provide depth-invariant magnification and to permit the specification of the collection angle for scattered light. To improve the threshold measurement sensitivity, a method is employed to suppress undesirable coherent imaging effects. A discussion of the tomographic inversion process is provided, including the results obtained from numerical simulation. Results obtained with this method from an ethylene diffusion flame are shown to be in close agreement with those previously obtained by sequential point-wise interrogation. Greenberg, Paul S. and Ku, Jerry C. Glenn Research Center NAG3-1265...
Download or read book Soot Fformation in Co flow and Counterflow Laminar Diffusion Flames of Fuel Mixtures written by Ahmet Emre Karatas and published by . This book was released on 2010 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the formation process of soot in the flames of even-carbon-numbered fuels, acetylene and its derivatives are suspected to be dominant. The addition of an odd-carbon-numbered fuel into these flames introduces methyl radicals and/or C3 chemistries, which are believed to (de)activate certain chemical pathways towards the production of soot. The resultant soot formation rate of the mixture could be higher than the sum of the respective rates of the mixture components, i.e., synergistic eff ect. In this work, the mixtures of butane isomers, ethylene-butane isomers, and propane-butane isomers were studied on a co-flow and a counterflow burner. Chemical effects were isolated from those of thermal and dilution by mixing isomers and comparing the mixtures including one isomer to those including the counterpart. Line of sight attenuation (LOSA) and laser-light extinction techniques were used for measuring soot volume fraction. The results provide information on synergistic effects in soot formation for the fuels used.
Download or read book Laser Transmission Measurements of Soot Extinction Coefficients in the Exhaust Plume of the X 34 60k lb Thrust Fastrac Rocket Engine written by C. C. Dobson and published by . This book was released on 2000 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Laser Diagnostics for Combustion Temperature and Species written by Alan C. Eckbreth and published by CRC Press. This book was released on 1996-10-10 with total page 636 pages. Available in PDF, EPUB and Kindle. Book excerpt: Focusing on spectroscopically-based, spatially-precise, laser techniques for temperature and chemical composition measurements in reacting and non-reacting flows, this book makes these powerful and important new tools in combustion research
Download or read book ON LINE MEASUREMENT OF PRIMARY FINE PARTICULATE MATTER written by and published by . This book was released on 1999 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt: The measurement of fine particulate in pulverized coal flames has several applications of importance. These include but are not limited to: (1) The detection of fine particulate in the effluent for pollution control; (2) The detection of soot and fuel burnout in real time within a boiler; and (3) The quantification of soot within coal flame for improved understanding of pulverized coal flame heat transfer and soot modeling. A method has been investigated using two-color extinction along a line of sight within the flame which provides a continuous real-time measurement of the soot concentration. The method uses two inexpensive HeNe lasers and simple light detectors. The results of testing the method on a pilot scale 0.2 MW pulverized coal reactor demonstrate the method is working well in a qualitative sense and an error analysis performed on the uncertainty of the assumed values demonstrates the method to be accurate to within " 30%. Additional experiments designed to quantify the measurement more accurately are ongoing. Measurements at the end of the reactor just prior to the exit showed soot could not be detected until the overall equivalence ratio became greater than 1.0. The detection limit for the method was estimated to be 1 x 10−8 soot volume fraction. Peak soot concentration was found to approach a level of 0.88 x 10−6 at the sootiest condition. The method was used to obtain an axial profile of soot concentration aligned with the down-fired pulverized coal flame for three different flame swirls of 0, 0.5 and 1.5 and an overall equivalence ratio of 1.2. The axial measurements showed the soot concentration to increase initially and level off to a constant maximum value. At 0.5 swirl the soot volume fraction increased more rapidly near the burner and both the 0.5 and 1.5 swirl cases showed that soot had reached a maximum by 0.9 m, but the 0 swirl soot concentration was still increasing. Previous measurements of species and velocity in the reactor suggest that the flame is lifted at zero swirl allowing O2 to be entrained and that the flame protrudes further down the reactor explaining the lower soot values measured. An evaluation of the potential for using this measurement technique on full scale boilers suggests that attenuation of the signal across a larger boiler distance is the largest obstacle. The beam would be expected to become completely attenuated under moderate sooting conditions; however, the longer pathlength would improve the ability of the method to measure very small amounts of soot escaping the main combustion zone.
Download or read book Optical Measurements of Soot in Premixed Flames written by Valerie Jean Lyons and published by . This book was released on 1988 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Computational and Experimental Study of Laminar Flames written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: During the past three years, our research has centered on an investigation of the effects of complex chemistry and detailed transport on the structure and extinction of hydrocarbon flames in coflowing axisymmetric configurations. We have pursued both computational and experimental aspects of the research in parallel on both steady-state and time-dependent systems. The computational work has focused on the application of accurate and efficient numerical methods for the solution of the steady-state and time-dependent boundary value problems describing the various reacting systems. Detailed experimental measurements were performed on axisymmetric coflow flames using two-dimensional imaging techniques. Previously, spontaneous Raman scattering, chemiluminescence, and laser-induced fluorescence were used to measure the temperature, major and minor species profiles. Particle image velocimetry (PIV) has been used to investigate velocity distributions and for calibration of time-varying flames. Laser-induced incandescence (LII) with an extinction calibration was used to determine soot volume fractions, while soot surface temperatures were measured with three-color optical pyrometry using a color digital camera. A blackbody calibration of the camera allows for determination of soot volume fraction as well, which can be compared with the LII measurements. More recently, we have concentrated on a detailed characterization of soot using a variety of techniques including time-resolved LII (TiRe-LII) for soot primary particles sizes, multi-angle light scattering (MALS) for soot radius of gyration, and spectrally-resolved line of sight attenuation (spec-LOSA). Combining the information from all of these soot measurements can be used to determine the soot optical properties, which are observed to vary significantly depending on spatial location and fuel dilution. Our goal has been to obtain a more fundamental understanding of the important fluid dynamic and chemical interactions in these flames so that this information can be used effectively in combustion modeling.
Download or read book Soot Particle Size and Number Density Measurements in a Direct Injection Diesel Engine Using Light Scattering Radiation and Extinction written by Dale Reif Tree and published by . This book was released on 1992 with total page 452 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Comparisons of the Soot Volume Fraction Using Gravimetric and Light Extinction Techniques written by and published by . This book was released on 1995 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Characterization of Soot Particles and Their Precursors Produced During the Combustion of Conventional and Alternative Fuels written by Thi Linh Dan Ngo and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Interest in biofuels has increased significantly in recent years as they could reduce dependence on fossil fuels and contribute to carbon-neutral growth. The influence of using biofuels on their exhaust emissions (CO,CO_2,NO_x,HC, etc.) has been studied widely. However, the effects of the nature of these alternative fuels on the physical and chemical properties of the particles and aromatic species produced are not fully understood. As part of this thesis work, we aim to study the emissions of soot particles and polycyclic aromatic hydrocarbons (PAHs) during the combustion of conventional and alternative fuels (biofuels) relevant to the automotive and aerospace sectors, while trying to highlight their influence on the formation of such pollutants. To achieve this goal, two laboratory combustors, a swirled turbulent jet burner and a Combustion Aerosol STandard (CAST), were used as soot generators. In addition, we have combined various complementary in-situ laser techniques, laser-induced incandescence and fluorescence (LII/LIF), and ex-situ two-step laser mass spectrometry (L2MS) and secondary ion mass spectrometry (SIMS). In a swirled turbulent jet flame for five fuels (Diesel, n-butanol, 50/50 Diesel/n-butanol mixture, Jet A1 and Synthetic Paraffinic Kerosene SPK), the LII and LIF profiles and properties of soot particles and their precursors with the height in the flame as well as their chemical composition were studied. Strong correlations between the results obtained with in-situ and ex-situ techniques have been demonstrated which allowed us to characterize these species spectrally and chemically. In addition, a new calibration method has been developed to directly deduce the soot volume fraction from the LII signal using the absolute radiance emitted from a light source having black body behavior. In parallel, experiments using the CAST device were conducted with aeronautical fuels (Jet A1 and SPK). In addition to the influence of the alternative fuel, the effects of a catalytic stripper (CS) on soot particles and volatile species were examined.
Download or read book Simultaneous Optical Measurement of Soot Volume Fraction Temperature and CO2 in Heptane Pool Fire written by M. Y. Choi and published by . This book was released on 1994 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Laser Induced Incandescence and Laser Induced Breakdown Spectroscopy Based Sensor Development written by Kemal Efe Eseller and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In this doctoral dissertation, two laser-based sensors were evaluated for different applications. Laser Induced Incandescence (LII) is a technique which can provide nonintrusive quantitative measurement of soot and it provides a unique diagnostic tool to characterize engine performance. Since LII is linearly proportional to the soot volume fraction, it can provide in situ, real time measurement of soot volume fraction with high temporal and spatial resolution. LII has the capability to characterize soot formation during combustion. The soot volume fraction from both flames and a soot generator was investigated with LII. The effects of experimental parameters, such as laser fluence, gate delay, gate width and various laser beam focusing, on LII signal was studied. Laser Induced Breakdown Spectroscopy (LIBS), a diagnostic tool for in situ elemental analysis, has been evaluated for on-line, simultaneous, multi-species impurity monitoring in hydrogen. LIBS spectra with different impurity levels of nitrogen, argon, and oxygen were recorded and the intensity of the spectral lines of Ar, O, N, and H observed were used to form calibration plots for impurities in hydrogen measurements. An ungated detection method for LIBS has been developed and applied to equivalence ratio measurements of CH4/air and biofuel/air. LIBS has also been used to quantitatively analyze the composition of a slurry sample. The quenching effect of water in slurry samples causes low LIBS signal quality with poor sensitivity. Univariate and multivariate calibration was performed on LIBS spectra of dried slurry samples for elemental analysis of Mg, Si and Fe. Calibration results show that the dried slurry samples give good correlation between spectral intensity and elemental concentration.
Download or read book Laser Diagnostics and Modeling of Combustion written by Kazuo Iinuma and published by Springer. This book was released on 1987 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Laser Velocimetry in the Low speed Wind Tunnels at Ames Research Center written by and published by . This book was released on 1984 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt:
