The effects of hydrogen addition on Fenimore NO formation in low-pressure, fuel-rich-premixed, burner-stabilized CH4/O2/N2 flames
| Autor: | A. V. Sepman, Anatoli Mokhov, V.M. van Essen, Howard Levinsky |
|---|---|
| Přispěvatelé: | Stratingh Institute of Chemistry |
| Rok vydání: | 2008 |
| Předmět: |
Mass flux
Laminar flames Hydrogen INDUCED FLUORESCENCE MEASUREMENTS Analytical chemistry Energy Engineering and Power Technology chemistry.chemical_element Combustion Mole fraction Methane COMBUSTION chemistry.chemical_compound Hydrogen addition PROMPT-NO chemistry.chemical_classification Premixed flame CH4/AIR FLAMES LIF Renewable Energy Sustainability and the Environment NOx formation MIXTURES Condensed Matter Physics HYDROCARBON Adiabatic flame temperature METHANE FLAMES IGNITION Fuel Technology Hydrocarbon chemistry NITRIC-OXIDE FORMATION NATURAL-GAS |
| Zdroj: | International Journal of Hydrogen Energy, 33(20), 5850-5857. PERGAMON-ELSEVIER SCIENCE LTD |
| ISSN: | 0360-3199 |
| Popis: | We investigate the effects of hydrogen addition on Fenimore NO formation in fuel-rich, low-pressure burner-stabilized CH4/O-2/N-2 flames. Towards this end, axial profiles of temperature and mole fractions of CH and NO are measured using laser-induced fluorescence (LIF). The experiments are performed at equivalent ratios of 1.3 and 1.5, using 0.25 mole fraction of hydrogen in the fuel, while varying the mass flux through the burner. The results are compared with those reported previously for burner-stabilized CH4/O-2/N-2 flames. The increased burning velocity caused by hydrogen addition is seen to result in a lower flame temperature as compared to methane flame stabilized at the same mass flux. This increase in burner stabilization upon hydrogen addition results in significantly lower CH mole fractions at phi = 1.3, but appears to have little effect on the CH profile at phi = 1.5. In addition, the results show that not only the maximum flame temperature is reduced upon hydrogen addition, but the local gas temperature in the region of the CH profile is lowered as well. The measured NO mole fractions are seen to decrease substantially for both equivalence ratios. Analysis of the factors responsible for Fenimore NO formation shows the reduction in temperature in the flame front to be the major factor in the decrease in NO mole fraction, with a significant contribution from the decrease in CH mole fraction at phi = 1.3. At phi = 1.5, the results suggest that the lower flame temperature upon hydrogen addition further retards the conversion of residual fixed-nitrogen species to NO under these rich conditions as compared to the equivalent methane flames. (C) 2008 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved. |
| Databáze: | OpenAIRE |
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