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Structure of Laminar Permanently Blue, Opposed-Jet Ethylene-Fueled Diffusion FlamesThe structure and state relationships of laminar soot-free (permanently blue) ethylene-fueled diffusion flames at various strain rates were studied both experimentally and computationally using an opposed-jet configuration. Measurements of gas velocities, temperatures, and compositions were carried out along the stagnation stream line. Corresponding predictions of flame structure were obtained, based on numerical simulations using several contemporary reaction mechanisms for methane oxidation. Flame conditions studied included ethylene-fueled opposed-jet diffusion flames having stoichiometric mixture fractions of 0.7 with measurements involving strain rates of 60-240/s and predictions involving strain rates of 0-1140/s at normal temperature and pressure. It was found that measured major gas species concentrations and temperature distributions were in reasonably good agreement with predictions using mechanisms due to GRI-Mech and Peters and that effects of preferential diffusion significantly influence flame structure even when reactant mass diffusivities are similar. Oxygen leakage to fuel-rich conditions and carbon monoxide leakage to fuel-lean conditions both increased as strain rates increased. Furthermore, increased strain rates caused increased fuel concentrations near the flame sheet, decreased peak gas temperatures, and decreased concentrations of carbon dioxide and water vapor throughout the flames. State relationships for major gas species and gas temperatures were found to exist over a broad range of strain rates, providing potential for significant computational simplifications for modeling purposes in some instances.
Document ID
20010119226
Document Type
Reprint (Version printed in journal)
Authors
Lin, K.-C. (Michigan Univ. Ann Arbor, MI United States)
Faeth, G. M. (Michigan Univ. Ann Arbor, MI United States)
Urban, D. L.
Date Acquired
August 20, 2013
Publication Date
December 15, 2000
Publication Information
Publication: Laminar Soot Processes (LSP)
ISSN: 0010-2180
Subject Category
Inorganic, Organic and Physical Chemistry
Funding Number(s)
CONTRACT_GRANT: N00014-93-0321
CONTRACT_GRANT: NAG3-1245
CONTRACT_GRANT: NAG3-2048
Distribution Limits
Public
Copyright
Other