Search NASA⌕ Search

SEARCH · Search NASA

Results for “carbon monoxide oxidation”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2

An analytical study of nitrogen oxides and carbon monoxide emissions in hydrocarbon combustion with added nitrogen, preliminary results

The effect of combustor operating conditions on the conversion of fuel-bound nitrogen (FBN) to nitrogen oxides NO sub x was analytically determined. The effect of FBN and of operating conditions on carbon monoxide (CO) formation was also studied. For these computations, the combustor was assumed to be a two stage, adiabatic, perfectly-stirred reactor. Propane-air was used as the combustible mixture and fuel-bound nitrogen was simulated by adding nitrogen atoms to the mixture. The oxidation of propane and formation of NO sub x and CO were modeled by a fifty-seven reaction chemical mechanism. The results for NO sub x and CO formation are given as functions of primary and secondary stage equivalence ratios and residence times.

Bittker, D. A.↗

Nano-crystalline porous tin oxide film for carbon monoxide sensing

A tin oxide sol is deposited on platinum electrodes (12) of a sensor (10). The sol is calcined at a temperature of 500 to 800.degree. C. to produce a thin film of tin oxide with a thickness of about 150 nm to 2 .mu. and having a nano-crystalline structure with good stability. The sensor rapidly detects reducing gases, such as carbon monoxide, or hydrocarbons and organic vapors. Sensors using films calcined at around 700.degree. C. have high carbon monoxide selectivity with a response time of around 4 minutes and a recovery time of 1 minute, and therefore provide good detection systems for detection of trace amounts of pollutants such as toxic and flammable gases in homes, industrial settings, and hospitals.

Liu, Chung-Chiun↗

Operational overview of Wallops Island instrument intercomparison - Carbon monoxide, nitric oxide, and hydroxyl instrumentation

NASA has initiated the Global Tropospheric Experiment (GTE) for the study of the chemistry of the global troposphere. One phase of GTE, Chemical Instrumentation Test and Evaluation (CITE), is concerned with the development and validation of measurement techniques for trace species which play important roles in the tropospheric chemical cycles. In connection with CITE 1 an intercomparison of instruments is conducted for the measurement of CO, NO, and OH. These species have been identified as critical for an understanding of homogeneous gas-phase chemistry in the troposphere. The present paper provides an operational overview of the first of three instrument intercomparison field missions conducted as part of GTE/CITE 1. The missions include one ground-based and two airborne missions, and were designed to characterize current capability of measuring ambient levels of CO, NO, and OH.

Gregory, G. L.↗

Field test to intercompare carbon monoxide, nitric oxide and hydroxyl instrumentation at Wallops Island, Virginia

Documentation of the first of three instrument intercomparisons conducted as part of NASA Global Tropospheric Experiment/Chemical Instrumentation Test and Evaluation (GTE/CITE-1) is given. This ground-based intercomparison was conducted during July 1983 at NASA Wallops Flight Facility. Instruments intercompared included one laser system and three grab-sample approaches for CO; two chemiluminescent systems and one laser-induced fluorescent (LIF) technique for NO; and two different LIF systems and a radiochemical tracer technique for OH. The major objectives of this intercomparison was to intercompare ambient measurements of CO, NO, and OH at a common site by using techniques of fundamentally different detection principles and to identify any major biases among the techniques prior to intercomparison on an aircraft platform. Included in the report are comprehensive discussions of workshop requirements, philosophies, and operations as well as intercomparison analyses and results. In addition, the large body of nonintercomparison data incorporated into the workshop measurements is summarized. The report is an important source document for those interested in conducting similar large and complex intercomparison tests as well as those interested in using the data base for purposes other than instrument intercomparison.

Gregory, Gerald L.↗

Operational overview of NASA GTE/CITE 1 airborne instrument intercomparisons - Carbon monoxide, nitric oxide, and hydroxyl instrumentation

An overview of the airborne intercomparisons of CO, NO, and OH instrumentation is presented in this first paper of the series on the NASA Global Tropospheric Experiment/Chemical Instrumentation Test and Evaluation (GTE/CITE 1). This paper provides the reader with background information about several important characteristics of the project. These include the overall objectives and approach, the measurements taken, the intercomparison protocol, aircraft platform, profiles of each aircraft flight, and the participants. A synopsis of the overall results of the CO, NO, and OH instrument intercomparisons is also included. Companion papers discuss the detailed results of the CO and NO intercomparison tests as well as pertinent scientific findings.

Beck, Sherwin M.↗

Oxidation-reduction catalyst and its process of use

This invention relates generally to a ruthenium stabilized oxidation-reduction catalyst useful for oxidizing carbon monoxide, and volatile organic compounds, and reducing nitrogen oxide species in oxidizing environments, substantially without the formation of toxic and volatile ruthenium oxide species upon said oxidizing environment being at high temperatures.

Jordan, Jeffrey D.↗

Reactions of HO2 with carbon monoxide and nitric oxide and of O/1 D/ with water.

Investigation of the reactions of the hydroperoxyl radical with carbon monoxide and nitric oxide in a static system, and reexamination of the reaction of O(1 D) with water. The HO2 radicals were generated by the photolysis of N2O at 2139 A in the presence of excess H2O or H2 and smaller amounts of CO and O2. The O(1 D) atoms produced from the photolysis of N2O react with H2O or with H2 to give OH radicals in the case of H2O or OH radicals and H atoms in the case of H2. With H2O, two OH radicals are produced for each O(1 D) removed at low pressures, but the OH yield drops as the pressure is raised. This drop is attributed to an insertion reaction which removes from 10 to 30% of the O(1 D) atoms at about 650 torr of H2O at 200 F. The OH radicals generated can react with either CO or H2 to produce H atoms, which then add to O2 to produce HO2. In the absence of NO, the HO2 radicals could react by two routes, while with NO present NO2 is produced in a long chain process.

Simonaitis, R.↗

NASA Tech Briefs, June 2010

Topics covered include: Situational Awareness from a Low-Cost Camera System; Data Acquisition System for Multi-Frequency Radar Flight Operations Preparation; Mercury Toolset for Spatiotemporal Metadata; Social Tagging of Mission Data; Integrating Radar Image Data with Google Maps; Demonstration of a Submillimeter-Wave HEMT Oscillator Module at 330 GHz; Flexible Peripheral Component Interconnect Input/Output Card; Interface Supports Lightweight Subsystem Routing for Flight Applications; MMIC Amplifiers and Wafer Probes for 350 to 500 GHz; Public Risk Assessment Program; Particle Swarm Optimization Toolbox; Telescience Support Center Data System Software; Update on PISCES; Ground and Space Radar Volume Matching and Comparison Software; Web-Based Interface for Command and Control of Network Sensors; Orbit Determination Toolbox; Distributed Observer Network; Computer-Automated Evolution of Spacecraft X-Band Antennas; Practical Loop-Shaping Design of Feedback Control Systems; Fully Printed High-Frequency Phased-Array Antenna on Flexible Substrate; Formula for the Removal and Remediation of Polychlorinated Biphenyls in Painted Structures; Integrated Solar Concentrator and Shielded Radiator; Water Membrane Evaporator; Modeling of Failure for Analysis of Triaxial Braided Carbon Fiber Composites; Catalyst for Carbon Monoxide Oxidation; Titanium Hydroxide - a Volatile Species at High Temperature; Selective Functionalization of Carbon Nanotubes: Part II; Steerable Hopping Six-Legged Robot; Launchable and Retrievable Tetherobot; Hybrid Heat Exchangers; Orbital Winch for High-Strength, Space-Survivable Tethers; Parameterized Linear Longitudinal Airship Model; and Physics of Life: A Model for Non-Newtonian Properties of Living Systems.

Source record↗

Emissions measurements for a lean premixed propane/air system at pressures up to 30 atmospheres

A series of experiments was conducted in which the emissions of a lean premixed system of propane and air were measured at pressures of 5, 10, 20 and 30 atm in a flametube apparatus. Measurements were made for inlet temperatures between 600K and 1000K and combustor residence times from 1.0 to 3.0 msec. A schematic of the test rig is presented along with graphs showing emissions measurements for nitric oxide, carbon monoxide, and UHC as functions of bustor residence time for various equivalence ratios, entrance temperatures and pressures; typical behavior of emissions as a function of equivalence ratio for a fixed residence time. Correlations of nitric oxide emission index with adiabatic flame temperature for a fixed residence time of 2 msec and pressures from 5 to 30 atm; and adiabatic flame temperature corresponding to CO breakpoint conditions for 2 msec residence time as a function of inlet temperature.

Roffe, G.↗

CFD assessment of the carbon monoxide and nitric oxide formation from RD-170 hot-fire testing at MSFC

Computational Fluid Dynamics (CFD) technology has been used to assess the exhaust plume pollutant environment of the RD-170 engine hot-firing on the F1 Test Stand at Marshall Space Flight Center. Researchers know that rocket engine hot-firing has the potential for forming thermal nitric oxides (NOx), as well as producing carbon monoxide (CO) when hydrocarbon fuels are used. Because of the complicated physics involved, however, little attempt has been made to predict the pollutant emissions from ground-based engine testing, except for simplified methods which can grossly underpredict and/or overpredict the pollutant formations in a test environment. The objective of this work, therefore, has been to develop a technology using CFD to describe the underlying pollutant emission physics from ground-based rocket engine testing. This resultant technology is based on a three-dimensional, viscous flow, pressure-based CFD formulation, where wet CO and thermal NOx finite-rate chemistry mechanisms are solved with a Penalty function method.

Wang, Ten-See↗

Exhaust emissions from a premixing, prevaporizing flame tube using liquid jet A fuel

Emissions of nitrogen oxides, carbon monoxide, and unburned hydrocarbons were measured in a burner where liquid Jet A fuel was sprayed into the heated air stream and vaporized upstream of a perforated plate flameholder. The burner was tested at inlet air temperatures at 640, 800, and 833 K, an inlet pressure of 5.6 X 100,000 N/m squared, a reference velocity of 25 m/sec, and equivalence ratios from lean blowout to 0.7. Nitrogen oxide levels of below 1.0 g NO2/kg fuel were obtained at combustion efficiencies greater than 99 percent. The measured emission levels for the liquid fuel agreed well with previously reported premixed gaseous propane data and agreed with well stirred reactor predictions. Autoignition of the premixed fuel air mixture was a problem at inlet temperatures above 650 K with 104 msec premixing time.

Marek, C. J.↗

Effect of hydrogen injection stability and emissions of an experimental premixed prevaporized propane burner

Hydrogen in quantities up to 5 percent by weight of the total fuel flow was injected into a premixed propane burner. The hydrogen was either premixed with the propane and air upstream of the burner or introduced as a torch at the flameholder. Emissions of total nitrogen oxides, carbon monoxide, and unburned hydrocarbon are reported as are combustion efficiencies and lean blowout limits. To maintain at least 99 percent combustion efficiency at a 700 K inlet mixture temperature with no hydrogen added, it was necessary to burn with a propane equivalence ratio of 0.525. When 4 percent hydrogen was premixed with the propane and air, a combustion efficiency greater than 99 percent was recorded at a propane equivalence ratio of 0.425. The total nitrogen oxides (NOx) emissions corresponding to these two conditions were 0.8 g NO2/kg equivalent propane and 0.44 g NO2/kg equivalent propane, respectively. The hydrogen torch did not reduce NOx emissions.

Anderson, D. N.↗

Molecular absorption parameters in atmospheric modelling

Molecular spectroscopic parameters are compiled for a number of infrared-active molecules occurring naturally in the terrestrial atmosphere. The following molecules are included in this compilation: water vapor; carbon dioxide; ozone; nitrous oxide; carbon monoxide; methane; and oxygen. The spectral region covered extends from less than 1 micron to the far infrared, and data are presented on more than 100,000 spectral lines. The parameters included in the compilation for each line are: frequency, intensity, half-width, energy of the lower state of the transition, vibrational and rotational identifications of the upper and lower energy states, an isotopic identification, and a molecular identification. Using this data compilation, band model parameters are presented for water vapor, carbon dioxide, and ozone averaged over 20 wavenumber intervals. Using these parameters in a random model formulation, transmittance spectra are provided and compared with both degraded monochromatic calculations and laboratory data.

Mcclatchey, R. A.↗

Summary of southeastern Virginia urban plume measurement data for August 4 and 5, 1977

The measurement program was conducted to define the characteristics of the Southeastern Virginia urban plume with emphasis on the photooxidant species. The measurement area was a rectangle approximately 200 km by 60 km centered in the Hampton Roads area of Tidewater Virginia. This area includes the cities of Norfolk, Virginia Beach, Chesapeake, Newport News, and Hampton. The data set presented includes aircraft measurements for ozone, nitrogen oxides, carbon monoxide, methane, and meteorological parameters such as dewpoint temperature. Surface level data for ozone are presented for 10 stations located throughout the test area. Comprehensive meteorological data from existing National Weather Service stations and special locations selected for the urban plume program are summarized.

Gregory, G. L.↗

Airborne atmospheric sampling system

The atmospheric sampling system developed for use on board commercial airliners as part of the Global Atmospheric Sampling Program (GASP) is described. The automated air-constituent measuring system is installed in a Boeing 747 airliner below the passenger cabin floor near the nose wheel well. It consists of an air sample flow system, composed of air inlet and pressurization systems, computerized data acquisition and system control units which direct system operation in 15 modes, and commercial instruments significantly modified to measure low levels of atmospheric constituents (ozone, water vapor, nitrogen oxides, carbon monoxide, chlorofluoromethanes, particulates, condensation nuclei, sulfates and nitrates). Flight and meteorological data, including air temperature and altitude, are also recorded. The system is designed for servicing at 14-day intervals, and to require a minimum of aircrew involvement.

Gustafsson, U. R. C.↗

Two-Stage Combustor Reduces Pollutant Emissions

By controlling fuel-to-air ratio of local reactants, pollutant emissions would be minimized in a proposed two-stage combustor for gas-turbine engines. It would use fuel-rich partial-oxidation stage and air-rich combustion stage to reduce emissions of nitrogen oxide, carbon monoxide and hydrocarbons. Combustor fuel-lean burning limit would be extended simultaneously.

Clayton, R. M.↗

Effect of flameholder pressure drop on emissions and performance of premixed-prevaporized combustors

Parametric tests were conducted to determine the effects of flameholder pressure drop on the emissions and performance of lean premixed-prevaporized combustors. A conical flameholder mounted in a diverging duct was tested with two values of flameholder blockage. Emissions of nitrogen oxides, carbon monoxide, carbon dioxide, and unburned hydrocarbons were measured for combustor entrance conditions of 600 to 800 K air temperature, 0.3 MPa to 0.5 MPa pressure, and 20 m/sec to 35 m/sec reference velocity. Jet A fuel was injected at flow rates corresponding to an equivalence ratio range from 0.8 down to the lean stability limit. Emission results for the high-blockage flameholder were a substantial improvement over the low-blockage emission results. A correlation of combustion efficiency with flameholder pressure drop was developed for pressure drops less than 9 percent.

Duerr, R. A.↗