Download or read book Laser Induced Incandescence LII written by and published by . This book was released on 2009 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Special Issue Laser induced Incandescence LII written by Kevin Thomson and published by . This book was released on 2009 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Special Issue Laser induced Incandescence LII 2014 written by and published by . This book was released on 2015 with total page 237 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Quantification of Laser induced Incandescence LII for Planar Time Resolved Measurements of the Soot Volume Fraction in a Combusting Diesel Jet written by Georg Wiltafsky and published by . This book was released on 1996 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Laser Induced Incandescence Detection Issues written by and published by . This book was released on 1996 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Using Laser Induced Incandescence to Measure Soot Smoke Concentrations written by and published by . This book was released on 1997 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Characterization and Demonstrations of Laser Induced Incandescence in Both Normal and Low Gravity written by and published by . This book was released on 1997 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Laser induced Incandescence Calibration Via Gravimetric Sampling written by and published by . This book was released on 1996 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Development and Characterization of Laser Induced Incandescence Towards Nanoparticle Soot Detection written by and published by . This book was released on 2000 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Laser Induced Incandescence in Microgravity written by and published by . This book was released on 1997 with total page 12 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 Time resolved Laser induced Incandescence from Multiwalled Carbon Nanotubes in Air written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We observed temporal laser-induced incandescence (LII) signals from multiwalled carbon nanotubes(MWCNTs) suspended in ambient air. Unlike previous LII experiments with soot particles, which showed that primary particles with larger diameters cool at slower timescales relative to smaller particles, we observed that thicker MWCNTs with larger outer diameters (ODs) cool at faster timescales relative to thinner MWCNTs with smaller ODs. We suggested a simple explanation of this effect, based on the solution of one-dimensional nonstationary heat conduction equation for the initial non-uniform heating of MWCNTs with ODs greater than the skin depth.

Download or read book Investigation of Laser induced Incandescence and Soot Vaporization Using Time Resolved Light Scattering in a Propane Diffusion Flame written by Gregory David Yoder and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT: Laser-induced incandescence is a technique that uses a pulsed laser beam to heat soot particles up to levels far above the background, causing them to emit radiation as essentially blackbodies, which can then be related to the total soot volume using suitable calibration schemes. However, the temperature reached by the laser-heated particles may cause the particles to begin to vaporize, thereby changing the parameter of interest, namely the total soot volume. The primary goal of this thesis is to investigate the particle vaporization due to LII using time-resolved laser light scattering. Based on the experimental measurements in a sooting propane diffusion flame, significant particle vaporization was found to occur on the time scale of the LII laser pulse. A model was developed to describe the particle temperature and volume as the particles are heated up and vaporized by the LII laser and as the particles subsequently cooled. This heat transfer model uses a fundamental energy balance along with the Planck distribution to model the LII signal as a function of time, and was then used to estimate the influence of particle vaporization on the time-resolved LII signal.

Download or read book Special Issue Laser Induced Incandescence from 9 to 11 May 2012 the Fifth International Workshop and Meeting on LII was Held at Le Touquet France written by and published by . This book was released on 2013 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Investigation of Premixed Sooting Flames by Combined Laser Induced Incandescence and Laser Induced Fluorescence written by Jaclyn Dunn and published by . This book was released on 2013 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study applies the techniques of laser induced incandescence (LII) and laser induced fluorescence (LIF) to investigate laminar sooting flames of premixed ethylene air. The approach involves using three different excitation wavelengths, together with temporally and spectrally resolved detection, generating a rich dataset concerning the formation of soot and polycyclic aromatic hydrocarbons (PAHs). Both prompt and delayed detection are used to perform LII when exciting with short wavelengths, both with issues involved. Delayed detection gives an underestimation of soot volume fraction at low heights in the flame, as a result of particle size effects. Prompt detection gives overestimation of soot volume fraction due to fluorescence in the measurement volume. It is shown that care must be taken with either method and through evaluation of the associated errors this study shows delayed detection provides a more accurate measure of soot volume fraction. The ability to obtain the fluorescence signals over a range of heights above burner and stoichiometries is demonstrated. The approach relies on heating the soot particles equivalently with three excitation wavelengths so the LII contribution to the signals can be subtracted, leaving only fluorescence. Fluorescence profiles obtained show similar features to those seen in the literature for invasive measurements, including a reduction in the fluorescence signal generated by 283 nm excitation at intermediate heights above the burner surface followed by a re-increase. Although the data do not allow species-selective measurements of PAHs, these in-situ measurements allow inferences to be drawn about changing concentration of different size classes of these precursors to soot formation. Finally the method of obtaining subtracting the LII contribution to signals was used to obtain fluorescence spectra both for 283 nm and 532 nm excitation. This showed the possibility that fluorescence can yield useful information that it is otherwise impossible to obtain in-situ under sooting conditions.

Download or read book Effects of Aggregate Morphology and Size on Laser induced Incandescence and Scattering from Black Carbon mature Soot written by and published by . This book was released on 2015 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: For this study, we have used a Single-Particle Soot Photometer (SP2) to measure time-resolved laser-induced incandescence (LII) and laser scatter from combustion-generated mature soot with a fractal dimension of 1.88 extracted from a burner. We have also made measurements on restructured mature-soot particles with a fractal dimension of 2.3-2.4. We reproduced the LII and laser-scatter temporal profiles with an energy- and mass-balance model, which accounted for heating of particles passed through a CW-laser beam over laser-particle interaction times of ~10 [mu]s. The results demonstrate a strong influence of aggregate size and morphology on LII and scattering signals. Conductive cooling competes with absorptive heating on these time scales; the effects are reduced with increasing aggregate size and fractal dimension. These effects can lead to a significant delay in the onset of the LII signal and may explain an apparent low bias in the SP2 measurements for small particle sizes, particularly for fresh, mature soot. In addition, the results reveal significant perturbations to the measured scattering signal from LII interference and suggest rapid expansion of the aggregates during sublimation.

Download or read book Laser induced Incandescence written by Christof Schultz and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: