Download or read book Laser Induced Fluorescence Measurements and Modeling of Nitric Oxide in High Pressure Premixed Flames written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-25 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt: Laser-induced fluorescence (LIF) has been applied to the quantitative measurement of nitric oxide (NO) in premixed, laminar, high-pressure flames. Their chemistry was also studied using three current kinetics schemes to determine the predictive capabilities of each mechanism with respect to NO concentrations. The flames studied were low-temperature (1600 less than T less than 1850K) C2H6/O2/N2 and C2H6/O2/N2 flames, and high temperature (2100 less than T less than 2300K) C2H6/O2/N2 flames. Laser-saturated fluorescence (LSF) was initially used to measure the NO concentrations. However, while the excitation transition was well saturated at atmospheric pressure, the fluorescence behavior was basically linear with respect to laser power at pressures above 6 atm. Measurements and calculations demonstrated that the fluorescence quenching rate variation is negligible for LIF measurements of NO at a given pressure. Therefore, linear LIF was used to perform quantitative measurements of NO concentration in these high-pressure flames. The transportability of a calibration factor from one set of flame conditions to another also was investigated by considering changes in the absorption and quenching environment for different flame conditions. The feasibility of performing LIF measurements of (NO) in turbulent flames was studied; the single-shot detection limit was determined to be 2 ppm. Reisel, John R. and Laurendeau, Normand M. Unspecified Center NASA-CR-195404, E-9248, NAS 1.26:195404 NAG3-1038; RTOP 537-02-20...

Download or read book Laser Induced Fluorescence Measurements and Modeling of Nitric Oxide in High pressure Premixed Flames written by and published by . This book was released on 1994 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Laser Induced Fluorescence Measurements and Modeling of Nitric Oxide in Counterflow Diffusion Flames written by and published by . This book was released on 2000 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Laser Induced Fluorescence Measurements and Modeling of Nitric Oxide in Counterflow Diffusion Flames written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-27 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt: The feasibility of making quantitative nonintrusive NO concentration ([NO]) measurements in nonpremixed flames has been assessed by obtaining laser-induced fluorescence (LIF) measurements of [NO] in counterflow diffusion flames at atmospheric and higher pressures. Comparisons at atmospheric pressure between laser-saturated fluorescence (LSF) and linear LIF measurements in four diluted ethane-air counterflow diffusion flames with strain rates from 5 to 48/s yielded excellent agreement from fuel-lean to moderately fuel-rich conditions, thus indicating the utility of a model-based quenching correction technique, which was then extended to higher pressures. Quantitative LIF measurements of [NO] in three diluted methane-air counterflow diffusion flames with strain rates from 5 to 35/s were compared with OPPDIF model predictions using the GRI (version 2.11) chemical kinetic mechanism. The comparisons revealed that the GRI mechanism underpredicts prompt-NO by 30-50% at atmospheric pressure. Based on these measurements, a modified reaction rate coefficient for the prompt-NO initiation reaction was proposed which causes the predictions to match experimental data. Temperature measurements using thin filament pyrometry (TFP) in conjunction with a new calibration method utilizing a near-adiabatic H2-air Hencken burner gave very good comparisons with model predictions in these counterflow diffusion flames. Quantitative LIF measurements of [NO] were also obtained in four methane-air counterflow partially-premixed flames with fuel-side equivalence ratios (phi(sub B)) of 1.45, 1.6, 1.8 and 2.0. The measurements were in excellent agreement with model predictions when accounting for radiative heat loss. Spatial separation between regions dominated by the prompt and thermal NO mechanisms was observed in the phi(sub B) = 1.45 flame. The modified rate coefficient proposed earlier for the prompt-NO initiation reaction improved agreement between code predictions and measurements in the re

Download or read book Measurements and Modeling of Nitric Oxide Formation in Counterflow Premixed CH4 O2 N2 Flames written by and published by . This book was released on 2000 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Measurements and Modeling of Nitric Oxide Formation in Counterflow Premixed Ch4 O2 N2 Flames written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-27 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt: Laser-induced fluorescence (LIF) measurements of NO concentration in a variety of CH4/O2/N2 flames are used to evaluate the chemical kinetics of NO formation. The analysis begins with previous measurements in flat, laminar, premixed CH4/O2/N2 flames stabilized on a water-cooled McKenna burner at pressures ranging from 1 to 14.6 atm, equivalence ratios from 0.5 to 1.6, and volumetric nitrogen/oxygen dilution ratios of 2.2, 3.1 and 3.76. These measured results are compared to predictions to determine the capabilities and limitations of the comprehensive kinetic mechanism developed by the Gas Research Institute (GRI), version 2.11. The model is shown to predict well the qualitative trends of NO formation in lean-premixed flames, while quantitatively underpredicting NO concentration by 30-50%. For rich flames, the model is unable to even qualitatively match the experimental results. These flames were found to be limited by low temperatures and an inability to separate the flame from the burner surface. In response to these limitations, a counterflow burner was designed for use in opposed premixed flame studies. A new LIF calibration technique was developed and applied to obtain quantitative measurements of NO concentration in laminar, counterflow premixed, CH4/O2/N2 flames at pressures ranging from 1 to 5.1 atm, equivalence ratios of 0.6 to 1.5, and an N2/O2 dilution ratio of 3.76. The counterflow premixed flame measurements are combined with measurements in burner-stabilized premixed flames and counterflow diffusion flames to build a comprehensive database for analysis of the GRI kinetic mechanism. Pathways, quantitative reaction path and sensitivity analyses are applied to the GRI mechanism for these flame conditions. The prompt NO mechanism is found to severely underpredict the amount of NO formed in rich premixed and nitrogen-diluted diffusion flames. This underprediction is traced to uncertainties in the CH kinetics as well as in the nitrogen oxidation chemistry. S

Download or read book Detailed Modeling and Laser induced Fluorescence Imaging of Nitric Oxide in a NH i seeded Non premixed Methane written by and published by . This book was released on 2001 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this paper we study the formation of NO in laminar, nitrogen diluted methane diffusion flames that are seeded with ammonia in the fuel stream. We have performed numerical simulations with detailed chemistry as well as laser-induced fluorescence imaging measurements for a range of ammonia injection rates. For comparison with the experimental data, synthetic LIF images are calculated based on the numerical data accounting for temperature and fluorescence quenching effects. We demonstrate good agreement between measurements and computations. The LIF corrections inferred from the simulation are then used to calculate absolute NO mole fractions from the measured signal. The NO formation in both doped and undoped flames occurs in the flame sheet. In the undoped flame, four different mechanisms including thermal and prompt NO appear to contribute to NO formation. As the NH3 seeding level increases, fuel-NO becomes the dominant mechanism and N2 shifts from being a net reactant to being a net product. Nitric oxide in the undoped flame as well as in the core region of the doped flames are underpredicted by the model; we attribute this mainly to inaccuracies in the NO recycling chemistry on the fuel-rich side of the flame sheet.

Download or read book Nitric Oxide Formation Analysis Using Chemical Reactor Modelling and Laser Induced Fluorescence Measurements on Industrial Swirl Flames written by Syed Mashruk and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Quantitative Measurements of Nitric Oxide Concentration in High Pressure Swirl Stabilized Spray Flames written by and published by . This book was released on 2000 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Nitric Oxide Concentration and Fluorescence Lifetime in Non premixed Atmospheric Pressure Flames written by James Joshua Driscoll and published by . This book was released on 2002 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 548 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental Assessment and Enhancement of Planar Laser Induced Fluorescence Measurements of Nitric Oxide in an Inverse Diffusion Flame written by and published by . This book was released on 1997 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1981 with total page 1372 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Quantitative Nitric Oxide Concentration and Temperature Imaging in Flames Over a Wide Pressure Range with Laser induced Flourescence written by Wolfgang Georg Bessler and published by . This book was released on 2003 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Joint Meeting of the U S Sections of the Combustion Institute Western States Central States Eastern States written by and published by . This book was released on 1999 with total page 954 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1987 with total page 338 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Nanoparticles from the Gasphase written by Axel Lorke and published by Springer Science & Business Media. This book was released on 2012-07-27 with total page 425 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gasphase synthesis of nanoparticles and nanostructured materials offers high chemical purity and crystalline quality as well as scalability up to industrial quantities. It is therefore highly attractive for both basic and applied science. This book gives a broad and coherent overview of the complete production and value chain from nanoparticle formation to integration into products and devices. Written by experts in the field – with backgrounds in electrical engineering, experimental and theoretical physics, materials science, and chemical engineering – the book offers a deep insight into the fabrication, characterization and application of nanoparticles from the gasphase. The first part of the book, “Formation”, covers chemical and growth kinetics, in-situ diagnostics, numerical simulation, process development and material deposition. In the second section, the reader is introduced to the structure and dynamics that lead to functional nanoscale systems and materials. The third section, “Properties and Applications”, provides a detailed discussion of the optical, electronic, magnetic and chemical characteristics of nanostructures and demonstrates how these can be used in tailored materials and devices.