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 Quantitative Measurements of Nitric Oxide Concentration in High Pressure Swirl Stabilized Spray 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 216 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lean direct-injection (LDI) spray flames offer the possibility of reducing NO(sub x) emissions from gas turbines by rapid mixing of the liquid fuel and air so as to drive the flame structure toward partially-premixed conditions. We consider the technical approaches required to utilize laser-induced fluorescence methods for quantitatively measuring NO concentrations in high-pressure LDI spray flames. In the progression from atmospheric to high-pressure measurements, the LIF method requires a shift from the saturated to the linear regime of fluorescence measurements. As such, we discuss quantitative, spatially resolved laser-saturated fluorescence (LSF), linear laser-induced fluorescence (LIF), and planar laser-induced fluorescence (PLIF) measurements of NO concentration in LDI spray flames. Spatially-resolved LIF measurements of NO concentration (ppm) are reported for preheated, LDI spray flames at pressures of two to five atmospheres. The spray is produced by a hollow-cone, pressure-atomized nozzle supplied with liquid heptane. NO is excited via the Q(sub 2)(26.5) transition of the gamma(0,0) band. Detection is performed in a two nanometer region centered on the gamma(0,1) band. A complete scheme is developed by which quantitative NO concentrations in high-pressure LDI spray flames can be measured by applying linear LIF. NO is doped into the reactants and convected through the flame with no apparent destruction, thus allowing a NO fluorescence calibration to be taken inside the flame environment. The in-situ calibration scheme is validated by comparisons to a reference flame. Quantitative NO profiles are presented and analyzed so as to better understand the operation of lean-direct injectors for gas turbine combustors. Moreover, parametric studies are provided for variations in pressure, air-preheat temperature, and equivalence ratio. Similar parametric studies are performed for lean, premixed-prevaporized flames to permit comparisons to those for LDI flames. Finall
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 Applied Combustion Diagnostics written by KoHse-HoingHaus and published by CRC Press. This book was released on 2002-04-26 with total page 744 pages. Available in PDF, EPUB and Kindle. Book excerpt: The editors have assembled a world-class group of contributors who address the questions the combustion diagnostic community faces. They are chemists who identify the species to be measured and the interfering substances that may be present; physicists, who push the limits of laser spectroscopy and laser devices and who conceive suitable measurement schemes; and engineers, who know combustion systems and processes. This book assists in providing guidance for the planning of combustion experiments, in judging research strategies and in conceiving new ideas for combustion research. It provides a snapshot of the available diagnostic methods and thier typical applications from the perspective of leading experts in the field.
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 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 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 The Formation of Nitric Oxide and the Detection of HCN in Premixed Hydrocarbon Air Flames at 1 Atmosphere written by F. Bachmaier and published by . This book was released on 1972 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: The NO concentration profiles of premixed hydrocarbon-air flames were measured using probe sampling and ultraviolet absorption of NO. The flames were stabilized on a Meker-type burner of 7 cm diameter at a pressure of 1 atm. Investigated fuels were CH4, C2H6, C2H4, C2H2, C3H8, n-C4H10, n-C6H14, i-C8H18, C6H6, C6H12, and gasoline. The measurements show the formation of nitric oxide according to the Zeldovich mechanism. In fuel rich flames the NO formation due to the Zeldovich mechanism would require unreasonably high concentrations of O atoms, and evidence is given for another way of NO formation in these flames. HCN has been found as an intermediate species and exceeds the NO concentration in very fuel rich flames. (Modified author abstract).
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 The Formation of Nitric Oxide in Diffusion Flames written by A. D. Tuteja and published by . This book was released on 1972 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NH and OH Concentration Profiles in a Stoichiometric CH4 N2O Flame by Laser Excited Fluorescence and Absorption Techniques written by William R. Anderson and published by . This book was released on 1982 with total page 43 pages. Available in PDF, EPUB and Kindle. Book excerpt: The concentration profiles of NH and OH were measured in an atmospheric pressure premixed laminar Ch4/N2O flame over a porous plug flat flame burner. Relative profiles were obtained by laser excited fluorescence for both compounds and normalized by laser absorption at a single point for NH. The OH concentration was high enough to allow absorption measurements at several points for comparison with fluorescence results. The steeply rising portions of the profiles occur at about the same height above the burner but the NH is confined to the primary reaction zone while the OH decay extends into the burnt gases. The apparent OH decay was found, using a simple analysis, to be consistent with second order kinetics as observed by previous workers on other flames. However, it should be noted that diffusion of OH is at least partially responsible for the apparent shape of the profile resulting in the second order decay kinetics found using the simple analysis. The decay rate is smaller than that observed by previous workers for CH4/air flames. Qualitative reasons for the different decay rates found in the studies are discussed in detail. A strong dependence of OH decay rate on final flame temperature, and hence the cooling rate peculiar to the burner concentration in CH4/air, CH4/NO, and H2/N2O flames were made in order to elucidate the flame chemistry. (Author).
Download or read book Energy Research Abstracts written by and published by . This book was released on 1992-07 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nitric Oxide Formation in a Lean Premixed Prevaporized Jet A Air Flame Tube written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2018-12-31 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental and analytical study was performed on a lean, premixed-prevaporized Jet A/air flame tube. The NO(x) emissions were measured in a flame tube apparatus at inlet temperatures ranging from 755 to 866 K (900 to 1100 F), pressures from 10 to 15 atm, and equivalence ratios from 0.37 to 0.62. The data were then used in regressing an equation to predict the NO(x) production levels in combustors of similar design. Through an evaluation of parameters it was found that NO(x) is dependent on adiabatic flame temperature and combustion residence time, yet independent of pressure and inlet air temperature for the range of conditions studied. This equation was then applied to experimental data that were obtained from the literature, and a good correlation was achieved. Lee, Chi-Ming and Bianco, Jean and Deur, John M. and Ghorashi, Bahman Glenn Research Center NASA-TM-105722, E-7121, NAS 1.15:105722 RTOP 537-01-11...
Download or read book Dissertation Abstracts International written by and published by . This book was released on 2005 with total page 884 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 2022-01-27 with total page 630 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book examines the variety of potential laser diagnostic techniques and presents a considerable theoretical foundation elucidating physics relevant to the laser diagnostics. It explains the Raman-based approaches for major species and temperature measurements.
Download or read book Effects of the Burner Stabilization on Nitric Oxide Formation and Destruction in Atmospheric pressure Flat Premixed Flames written by Alexei Vladimirovich Sepman and published by . This book was released on 2006 with total page 157 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Optical Measurements of Atomic Oxygen Concentration Temperature and Nitric Oxide Production Rate in Flames written by Franklin Henry Myhr and published by . This book was released on 1998 with total page 418 pages. Available in PDF, EPUB and Kindle. Book excerpt:
