Download or read book Soot Particle Size Measurements in Laminar Premixed Ethylene Flames with Laser induced Incandescence and Scanning Mobility Particle Sizer written by Chung-Yuan Yin and published by . This book was released on 2009 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: Laser-induced incandescence (LII) is used to obtain soot particle size measurements in laminar premixed ethylene flames. The LII signals are calibrated by comparing with the particle diameters measured with scanning mobility particle sizer (SMPS). Issues related to the calibration of LII with SMPS are discussed, such as the effects of equivalence ratio and laser fluence. LII and SMPS have similar sensitivities to equivalence ratio in terms of total surface area and total volume, but the equivalence ratio needs to be carefully controlled as it highly affects the results. High laser fluence affects LII results by vaporizing soot particles, which reduces particle size. The effect of high laser fluence is particularly noticeable in the flame positions near the surrounding air such as at high flame heights and the outer combustion zone of nonpremixed flames where particle oxidation takes place. Overall, the comparison between LII and SMPS data yields encouraging results as they exhibit similar trends. The correspondence of LII and SMPS implies that SMPS could be applied as a valuable tool to calibrate LII signals and avoid the necessity of developing complex LII models.

Download or read book Applied Optics written by and published by . This book was released on 2005 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Spatially resolved Measurement and Computation of Soot Particle Size Distribution Function in a Laminar Premixed Ethylene Flame written by Bin Zhao and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Nanoparticles in medicine and environment written by J.C. Marijnissen and published by Springer Science & Business Media. This book was released on 2009-12-01 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt: A huge effort is put into the science of nanoparticles and their production. In many cases it is unavoidable that nanoparticles are released into the environment, either during the production processes or during the use of a product made from these particles. It is also realized that combustion processes like traffic and power plants release nanoparticles into the atmosphere. However it is not known how nanoparticles interact with the human body, especially upon inhalation. At the same time research activities are devoted to understand how nano-sized medicine particles can be used to administer medicines via inhalation. In any case it is absolutely necessary to know how the nanoparticles interfere with the inhalation system, how they deposit and affect on the human system. Three main themes are discussed: Nanoparticle sources and production Nanoparticle inhalation and deposition Toxicological and medical consequences of nanoparticles Each theme is covered comprehensively, starting at nano-quantum effects up to technical and medical applications such as measuring equipment and inhalation instrumentation. This book brings together all sub-disciplines in the field related to aerosol nanoparticles. Each chapter is written by a world expert, giving the state of the art information and challenging open questions. The last chapter summarizes in an interdisciplinary way what is already known and what still is ahead of us.

Download or read book Laser Induced Incandescence of Soot for High Pressure Combustion Diagnostics written by Daniel Dennis Emile Cormier and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Laser Induced Incandescence of Soot at High Pressures written by Sanaz Ghasemi and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Oil Gas Science and Technology written by and published by . This book was released on 2006 with total page 372 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 Imaging Measurements of Soot Particle Size and Soot Volume Fraction with Laser induced Incandescence at Diesel Engine Conditions written by Emre Cenker and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental Study of Soot Formation in Laminar Premixed Flames of Fuels of Interest for Automobile and Aeronautics written by Christopher Betrancourt and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Emission of soot formed from incomplete combustion of fossil fuels, biofuels and biomass is a serious concern due to soot's harmful impact on human health, environment and its radiative forcing on climate. Gaining fundamental understanding of soot formation, particularly the nucleation step leading to the formation of the nascent soot particles, is critical to develop reliable predictive soot models and to help the design of more efficient and cleaner combustion devices. This work demonstrates that nascent soot particles in the size range of 2-4 nm are able to emit a black body radiation by combined Laser Induced Incandescence (LII), scanning mobility particle sizer (SMPS) and helium-ion microscopy (HIM). These nascent soot particles are investigated in nucleation premixed flames in which soot particles are essentially formed by nucleation, without growth by soot surface processes and in standard sooting premixed flames in which growth processes occur. This work provides an extensive database for improvement of kinetics modelling of sooting flames with a focus on the soot nucleation in flames. Two kinds of fuels have been selected: n-butane and mixture of n-butane and n-propylbenzene. For each fuels two flames have been studied: a nucleation and a standard sooting flames. The database consist of species profiles obtained by online gas chromatography, temperature profiles measured by Laser induced fluorescence thermometry, soot volume fraction profiles obtained by LII calibrated by cavity ring-down extinction and particles size distributions obtained in n-butane flames by SMPS and HIM. From this database effect of equivalence ratio and fuel composition is analyzed.

Download or read book Soot Growth in Laminar Premixed Flames written by Fang Xu and published by . This book was released on 1999 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Ultra fine Soot Investigation in Flames written by Stephen William Lasher and published by . This book was released on 1999 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Measurements of Soot Formation and Hydroxyl Concentration in Near Critical Equivalence Ratio Premixed Ethylene Flame written by Michael Andrew Inbody and published by . This book was released on 1993 with total page 504 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Development and Validation of an Experimental Apparatus for the Characterization of Soot in a Laminar Co flow Diffusion Flame Using Laser induced Incandescence written by Babak Borshanpour and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Characterization of Soot Particles in Laminar Diffusion by Laser induced Incandescence written by Alexandre Dias Flügel and published by . This book was released on 2018 with total page 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 Measurements of Soot Formation and Hydroxyl Concentration in Near Critical Equivalence Ratio Premixed Ethylene Flame written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-27 with total page 504 pages. Available in PDF, EPUB and Kindle. Book excerpt: The testing and development of existing global and detailed chemical kinetic models for soot formation requires measurements of soot and radical concentrations in flames. A clearer understanding of soot particle inception relies upon the evaluation and refinement of these models in comparison with such measurements. We present measurements of soot formation and hydroxyl (OH) concentration in sequences of flat premixed atmospheric-pressure C2H4/O2/N2 flames and 80-torr C2H4/O2 flames for a unique range of equivalence ratios bracketting the critical equivalence ratio (phi(sub c)) and extending to more heavily sooting conditions. Soot volume fraction and number density profiles are measured using a laser scattering-extinction apparatus capable of resolving a 0.1 percent absorption. Hydroxyl number density profiles are measured using laser-induced fluorescence (LIF) with broadband detection. Temperature profiles are obtained from Rayleigh scattering measurements. The relative volume fraction and number density profiles of the richer sooting flames exhibit the expected trends in soot formation. In near-phi(sub c) visibility sooting flames, particle scattering and extinction are not detected, but an LIF signal due to polycyclic aromatic hydrocarbons (PAH's) can be detected upon excitation with an argon-ion laser. A linear correlation between the argon-ion LIF and the soot volume fraction implies a common mechanistic source for the growth of PAH's and soot particles. The peak OH number density in both the atmospheric and 80-torr flames declines with increasing equivalence ratio, but the profile shape remains unchanged in the transition to sooting, implying that the primary reaction pathways for OH remain unchanged over this transition. Chemical kinetic modeling is demonstrated by comparing predictions using two current reaction mechanisms with the atmospheric flame data. The measured and predicted OH number density profiles show good agreement. The predicted benzene number...