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Title: Stretch rate of tubular premixed flames

Abstract

Following Seshadri and Williams solution describing the flow field for the opposed jet burner, the analytical solution is given for the flow field of two other burners: the opposed tubular burner and the tubular burner. Under plug flow boundary conditions, it is shown that the stretch rate at the stagnation surface of the opposed tubular burner is k=pV/(R{sub 2}-R{sub 1}) for the case of equal velocities and equal densities (i.e., r{sub 1}=r{sub 2} and V{sub 1}=-V{sub 2}=V). For the tubular burner, the stretch rate at the center of the burner is k=pV/R{sub 2}. The comparison of the numerical simulation and analytical solution is carried out to verify the analytical solution. (author)

Authors:
; ;  [1]
  1. Mechanical Engineering Department, Vanderbilt University, Nashville, TN 37235 (United States)
Publication Date:
OSTI Identifier:
20727312
Resource Type:
Journal Article
Resource Relation:
Journal Name: Combustion and Flame; Journal Volume: 145; Journal Issue: 1-2; Other Information: Elsevier Ltd. All rights reserved
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; FLAMES; MATHEMATICAL MODELS; ANALYTICAL SOLUTION; BURNERS

Citation Formats

Wang, Peiyong, Wehrmeyer, Joseph A., and Pitz, Robert W. Stretch rate of tubular premixed flames. United States: N. p., 2006. Web. doi:10.1016/j.combustflame.2005.09.015.
Wang, Peiyong, Wehrmeyer, Joseph A., & Pitz, Robert W. Stretch rate of tubular premixed flames. United States. doi:10.1016/j.combustflame.2005.09.015.
Wang, Peiyong, Wehrmeyer, Joseph A., and Pitz, Robert W. Sat . "Stretch rate of tubular premixed flames". United States. doi:10.1016/j.combustflame.2005.09.015.
@article{osti_20727312,
title = {Stretch rate of tubular premixed flames},
author = {Wang, Peiyong and Wehrmeyer, Joseph A. and Pitz, Robert W.},
abstractNote = {Following Seshadri and Williams solution describing the flow field for the opposed jet burner, the analytical solution is given for the flow field of two other burners: the opposed tubular burner and the tubular burner. Under plug flow boundary conditions, it is shown that the stretch rate at the stagnation surface of the opposed tubular burner is k=pV/(R{sub 2}-R{sub 1}) for the case of equal velocities and equal densities (i.e., r{sub 1}=r{sub 2} and V{sub 1}=-V{sub 2}=V). For the tubular burner, the stretch rate at the center of the burner is k=pV/R{sub 2}. The comparison of the numerical simulation and analytical solution is carried out to verify the analytical solution. (author)},
doi = {10.1016/j.combustflame.2005.09.015},
journal = {Combustion and Flame},
number = 1-2,
volume = 145,
place = {United States},
year = {Sat Apr 15 00:00:00 EDT 2006},
month = {Sat Apr 15 00:00:00 EDT 2006}
}
  • Flame stretch measurements in a premixed, lean methane-air, V-flame interacting with a Karman vortex street have been made using a particle image velocimeters. The flame curvature and strain rate along the flame have been measured over the range of {minus}2.0--1.0 mm{sup {minus}1} and {minus}175--170 s{sup {minus}1}, respectively, which corresponds to a range of flame stretch from {minus}475--200 s{sup {minus}1}. Results indicate that the curvature and strain rate are statistically independent. Flame stretch statistics based on individual flames are also considered since each flame represents a particular phase within the regular and periodic interaction cycle studied. These results indicate that formore » a particular flame the average stretch rate becomes independent of the average flame strain rate. A comparison among PIV measurements, OH Planar laser-induced fluorescence (OH-PLIF) measurements, and numerical simulation reveals similar flame stretch statistics. Qualitative measurements concerning flame shape and the relative location of vortices within the reactant flow are also discussed.« less
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