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Book Development of UV Optical Measurements of Nitric Oxide and Hydroxyl Radical at the Exit of High Pressure Gas Turbine Combustors

Download or read book Development of UV Optical Measurements of Nitric Oxide and Hydroxyl Radical at the Exit of High Pressure Gas Turbine Combustors written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-02 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: Measurements of nitric oxide (NO) and hydroxyl radical (OR) have been made in a laboratory flat flame at pressures up to 30 atm using line-of-sight resonant absorption. Data are reported at equivalence ratios of 0.98 and 1.3 and pressures of 1, 5, 10, 20 and 30 atm. The performance of the in-situ LTV absorption technique with assessed at these elevated pressures by comparing the measured absorption with those predicted by detailed theoretical spectroscopic models for NO and OH. Previous to this experiment the resonant models had not been verified at pressures greater than two atmospheres. Agreement within 25% was found between the measurements and predictions with only slight modification of the existing models for both NO and OH to account for line center shifting and pressure broadening. Continuum interference of hot oxygen (O2) on the NO absorption spectra was not significant in the interpretation of the data. The optical methods used in this study are distinct from laser-based diagnostics such as laser induced fluorescence and, hence, have the potential to provide independent verification of the laser-based measurements. The methodology is also of sufficient simplicity to be hardened into a portable optical measurement system that can be deployed in gas turbine engine test cells. A miniature fiber optic couple portable instrument is described. Liscinsky, D. S. and Knight, B. A. and Shirley, J. A. Glenn Research Center NAS3-27593; RTOP 538-08-12...

Book Nitric Oxide Measurement Study

Download or read book Nitric Oxide Measurement Study written by and published by . This book was released on 1981 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Comparison of UV Absorption Measurements with Probe Sampling Measurements of Nitric Oxide Concentration in a Jet Engine Combustor Exhaust

Download or read book Comparison of UV Absorption Measurements with Probe Sampling Measurements of Nitric Oxide Concentration in a Jet Engine Combustor Exhaust written by J. D. Few and published by . This book was released on 1976 with total page 33 pages. Available in PDF, EPUB and Kindle. Book excerpt: Measurements were made in the exhaust of a T-56 turbine engine combustor of nitric oxide (NO) concentration using an ultraviolet (UV) spectral absorption technique. The measurements were made at two axial locations in the combustor exhaust stream. The NO gamma-band radiation at 2265 A produced in a resonance source was passed through the exhaust stream, and the amount transmitted was recorded. The mathematical model used to determine the NO concentration from the absorption measurements is described. Pressure and temperature broadening effects on the measured absorption are considered in the line-by-line transmission calculation. The line-of-sight absorption measurements through the axisymmetric exhaust stream were converted to local concentration values via an iterative radial inversion computation. These in situ measurements are compared to NO concentration values obtained by conventional probe-sampling techniques using a chemiluminescent analyzer. The in situ measurements of the NO concentration were larger than the probe-sampled measurements by from 50 to 80 percent, depending upon the measurement location in the exhaust stream. (Author).

Book Development of All Solid State Sensors for Measurement of Nitric Oxide and Ammonia Concentrations by Optical Absorption in Particle Laden Combustion Exhaust Streams

Download or read book Development of All Solid State Sensors for Measurement of Nitric Oxide and Ammonia Concentrations by Optical Absorption in Particle Laden Combustion Exhaust Streams written by Robert P. Lucht and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: An all-solid-state continuous-wave (cw) laser system for ultraviolet absorption measurements of the nitric oxide (NO) molecule has been developed and demonstrated. For the NO sensor, 250 nW of tunable cw ultraviolet radiation is produced by sum-frequency-mixing of 532-nm radiation from a diode-pumped Nd:YAG laser and tunable 395-nm radiation from an external cavity diode laser (ECDL). The sum-frequency-mixing process occurs in a beta-barium borate crystal. The nitric oxide absorption measurements are performed by tuning the ECDL and scanning the sum-frequency-mixed radiation over strong nitric oxide absorption lines near 226 nm. In Year 1 of the research, the nitric oxide sensor was used for measurements in the exhaust of a coal-fired laboratory combustion facility. The Texas A & M University boiler burner facility is a 30 kW (100,000 Btu/hr) downward-fired furnace with a steel shell encasing ceramic insulation. Measurements of nitric oxide concentration in the exhaust stream were performed after modification of the facility for laser based NOx diagnostics. The diode-laser-based ultraviolet absorption measurements were successful even when the beam was severely attenuated by particulate in the exhaust stream and window fouling. Single-laser-sweep measurements were demonstrated with an effective time resolution of 100 msec, limited at this time by the scan rate of our mechanically tuned ECDL system. In Year 2, the Toptica ECDL in the original system was replaced with a Sacher Lasers ECDL. The mode-hop-free tuning range and tuning rate of the Toptica ECDL were 25 GHz and a few Hz, respectively. The mode-hop-free tuning range and tuning rate of the Sacher Lasers ECDL were 90 GHz and a few hundred Hz, respectively. The Sacher Lasers ECDL thus allows us to scan over the entire NO absorption line and to determine the absorption baseline with increased accuracy and precision. The increased tuning rate is an advantage in that data can be acquired much more rapidly and the absorption measurements are less susceptible to the effects of transient fluctuations in the properties of the coal combustor exhaust stream. Gas cell measurements were performed using the NO sensor with the new ECDL, and a few spectra were acquired from the coal exhaust stream. However, the laser diode in the new ECDL failed during the coal combustor tests. In Year 3, however, we obtained a new GaN laser diode for our ECDL system, installed it, and completed an extensive series of measurements in the Texas A & M coal-fired laboratory combustion facility. The combustor was operated with coal and coal/biomass as fuels, with and without reburn, and with and without ammonia injection. Several different fuel equivalence ratios were investigated for each operating condition.

Book Nitric Oxide Measurement Study

Download or read book Nitric Oxide Measurement Study written by and published by . This book was released on 1980 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Development of All Solid State Sensors for Measurement of Nitric Oxide and Ammonia Concentrations by Optical Absorption in Particle Laden Combustion Exhaust Streams

Download or read book Development of All Solid State Sensors for Measurement of Nitric Oxide and Ammonia Concentrations by Optical Absorption in Particle Laden Combustion Exhaust Streams written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: An all-solid-state continuous-wave (cw) laser system for ultraviolet absorption measurements of the nitric oxide (NO) molecule has been developed and demonstrated. For the NO sensor, 250 nW of tunable cw ultraviolet radiation is produced by sum-frequency-mixing of 532-nm radiation from a diode-pumped Nd:YAG laser and tunable 395-nm radiation from an external cavity diode laser (ECDL). The sum-frequency-mixing process occurs in a beta-barium borate crystal. The nitric oxide absorption measurements are performed by tuning the ECDL and scanning the sum-frequency-mixed radiation over strong nitric oxide absorption lines near 226 nm. In Year 1 of the research, the nitric oxide sensor was used for measurements in the exhaust of a coal-fired laboratory combustion facility. The Texas A & M University boiler burner facility is a 30 kW (100,000 Btu/hr) downward-fired furnace with a steel shell encasing ceramic insulation. Measurements of nitric oxide concentration in the exhaust stream were performed after modification of the facility for laser based NOx diagnostics. The diode-laser-based ultraviolet absorption measurements were successful even when the beam was severely attenuated by particulate in the exhaust stream and window fouling. Single-laser-sweep measurements were demonstrated with an effective time resolution of 100 msec, limited at this time by the scan rate of our mechanically tuned ECDL system. In Year 2, the Toptica ECDL in the original system was replaced with a Sacher Lasers ECDL. The mode-hop-free tuning range and tuning rate of the Toptica ECDL were 25 GHz and a few Hz, respectively. The mode-hop-free tuning range and tuning rate of the Sacher Lasers ECDL were 90 GHz and a few hundred Hz, respectively. The Sacher Lasers ECDL thus allows us to scan over the entire NO absorption line and to determine the absorption baseline with increased accuracy and precision. The increased tuning rate is an advantage in that data can be acquired much more rapidly and the absorption measurements are less susceptible to the effects of transient fluctuations in the properties of the coal combustor exhaust stream. Gas cell measurements were performed using the NO sensor with the new ECDL, and a few spectra were acquired from the coal exhaust stream. However, the laser diode in the new ECDL failed during the coal combustor tests. In Year 3, however, we obtained a new GaN laser diode for our ECDL system, installed it, and completed an extensive series of measurements in the Texas A & M coal-fired laboratory combustion facility. The combustor was operated with coal and coal/biomass as fuels, with and without reburn, and with and without ammonia injection. Several different fuel equivalence ratios were investigated for each operating condition. A series of spectral simulations was performed using the HITRAN code to investigate the potential sensitivity of absorption measurements of ammonia in different spectral regions. It was concluded that ammonia absorption features in the 3000-nm spectral region would be hard to measure due to water vapor interferences. We will concentrate on the spectral region near 1530 nm, where other researchers have had some success in measuring ammonia.

Book Optical in Situ Versus Probe Measurements of Nitric Oxide Concentration as a Function of Axial Position in a Combustor Exhaust

Download or read book Optical in Situ Versus Probe Measurements of Nitric Oxide Concentration as a Function of Axial Position in a Combustor Exhaust written by J. D. Few and published by . This book was released on 1979 with total page 37 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nitric oxide (N0) concentration was measured at three axial stations (6.5, 12, and 25 nozzle diameters downstream of a combustor nozzle exit) in a jet engine combustor exhaust by a gas-sampling probe in conjunction with conventional gas analyzers and an optical resonance absorption technique. The gas analyzer system permitted measurements of NO, NO sub x, CO, CO sub 2, and C sub x, H sub y (total hydrocarbons) whereas the optical absorption technique permitted measurement of NO only. The combustor was exhausted into a test cell of slightly less than atmospheric pressure and was operated at an inlet air temperature of 589 K, a total pressure of 344.3 kPa, and a fuel-to-air ratio (f/a) of 0.02. A multiprobe rake was used to acquire emissions, total pressure and temperature, and static pressure data at the measurement stations. The measurements of total pressure, total temperature, and measured static pressure were used to determine static temperature and pressure profiles at each measurement station, which are required for determining NO concentration by the optical absorption technique.

Book International Aerospace Abstracts

Download or read book International Aerospace Abstracts written by and published by . This book was released on 1998 with total page 920 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Reevaluation of Nitric Oxide Concentration in Exhaust of Jet Engines and Combustors

Download or read book Reevaluation of Nitric Oxide Concentration in Exhaust of Jet Engines and Combustors written by J. D. Few and published by . This book was released on 1981 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt: Several measurements of nitric oxide (NO) concentrations in the exhaust of jet engines and combustors by probe sampling and ultraviolet (UV) resonance absorption have been reported. Generally, the optically determined concentrations have exceeded the probe determined values appreciably. The theoretical basis for the determination of the NO concentration from absorption measurements has recently been reexamined, and the values previously reported were redetermined. Upon reexamination, the parameter a (the ratio of collisional plus natural half-width to the Doppler half-width) was found to obey the relationship a = C P/T sub 0 to the 1.5 power where P is the pressure in atmospheres, T is the temperature in K, and C is a constant. The value of C was found to be 3.81 (+ or - 40) x 10,000 k to the 1.5 power/atm. The major conclusion of previous studies remains unchanged, namely, that optically determined NO concentrations may be a factor of 5 larger than probe determined values or may be the same, depending on the combustion gas flow conditions and/or probe design. However, certain optically determined NO concentrations varied by as much as 46 percent from previously reported values because of alternations made to the theory and parameters.

Book Nitric Oxide Formation in Gas Turbine Engines

Download or read book Nitric Oxide Formation in Gas Turbine Engines written by Thomas Mikus and published by . This book was released on 1978 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book A Study of the Reaction Between Nitric Oxide and Hydrogen Sulphide

Download or read book A Study of the Reaction Between Nitric Oxide and Hydrogen Sulphide written by Jerry Albert Pierce and published by . This book was released on 1928 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: