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Title: Fractal approach to the evaluation of burning rates in the vicinity of the piston in a spark-ignition engine

Abstract

The burning rate in the vicinity of a piston is estimated from a fractal analysis. The fractal parameters are determined from laser sheet tomography flame images for methane-air mixtures with three equivalence ratios (1, 0.9, 0.8) in a transparent spark-ignition engine. Two imaging configurations were used: five horizontal planes placed at different distances from the piston (0, 1, 2, 3, and 5 mm) and a vertical one passed through the center of the combustion chamber. The methodology proposed by Foucher et al. [F. Foucher, S. Burnel, C. Mounaim-Rousselle, Proc. Combust. Inst. 29 (2002) 751-757] allows the effect of cyclic variations to be avoided. The fractal formulation is modified to take into account the flame-piston distance and flame quenching. Far from the piston, evolution of the fractal dimension versus q{sup '}/S{sub L}{sup 0} is found to be in good agreement with literature results. Near the piston, the fractal dimension evolves significantly when the distance is about twice the integral length scale and tends toward 2, the fractal dimension of a laminar flame front. The quenching ratio parameter Q{sub R} is introduced to consider the quenching of the flame by the piston. Finally, the burning rate is determined as a function ofmore » the distance between the wall and the mean flame contour and compared to a flame density approach, and similar results are found.« less

Authors:
;  [1]
  1. Laboratoire de Mecanique et d'Energetique, Polytech'Orleans, Universite d'Orleans, Site Leonard de Vinci, 45072 Orleans cedex 1 (France)
Publication Date:
OSTI Identifier:
20677737
Resource Type:
Journal Article
Resource Relation:
Journal Name: Combustion and Flame; Journal Volume: 143; Journal Issue: 3; Other Information: Elsevier Ltd. All rights reserved
Country of Publication:
United States
Language:
English
Subject:
33 ADVANCED PROPULSION SYSTEMS; SPARK IGNITION ENGINES; COMBUSTION KINETICS; FRACTALS; METHANE; AIR; PISTONS; DISTANCE

Citation Formats

Foucher, F., and Mounaim-Rousselle, C.. Fractal approach to the evaluation of burning rates in the vicinity of the piston in a spark-ignition engine. United States: N. p., 2005. Web. doi:10.1016/j.combustflame.2005.06.007.
Foucher, F., & Mounaim-Rousselle, C.. Fractal approach to the evaluation of burning rates in the vicinity of the piston in a spark-ignition engine. United States. doi:10.1016/j.combustflame.2005.06.007.
Foucher, F., and Mounaim-Rousselle, C.. Tue . "Fractal approach to the evaluation of burning rates in the vicinity of the piston in a spark-ignition engine". United States. doi:10.1016/j.combustflame.2005.06.007.
@article{osti_20677737,
title = {Fractal approach to the evaluation of burning rates in the vicinity of the piston in a spark-ignition engine},
author = {Foucher, F. and Mounaim-Rousselle, C.},
abstractNote = {The burning rate in the vicinity of a piston is estimated from a fractal analysis. The fractal parameters are determined from laser sheet tomography flame images for methane-air mixtures with three equivalence ratios (1, 0.9, 0.8) in a transparent spark-ignition engine. Two imaging configurations were used: five horizontal planes placed at different distances from the piston (0, 1, 2, 3, and 5 mm) and a vertical one passed through the center of the combustion chamber. The methodology proposed by Foucher et al. [F. Foucher, S. Burnel, C. Mounaim-Rousselle, Proc. Combust. Inst. 29 (2002) 751-757] allows the effect of cyclic variations to be avoided. The fractal formulation is modified to take into account the flame-piston distance and flame quenching. Far from the piston, evolution of the fractal dimension versus q{sup '}/S{sub L}{sup 0} is found to be in good agreement with literature results. Near the piston, the fractal dimension evolves significantly when the distance is about twice the integral length scale and tends toward 2, the fractal dimension of a laminar flame front. The quenching ratio parameter Q{sub R} is introduced to consider the quenching of the flame by the piston. Finally, the burning rate is determined as a function of the distance between the wall and the mean flame contour and compared to a flame density approach, and similar results are found.},
doi = {10.1016/j.combustflame.2005.06.007},
journal = {Combustion and Flame},
number = 3,
volume = 143,
place = {United States},
year = {Tue Nov 01 00:00:00 EST 2005},
month = {Tue Nov 01 00:00:00 EST 2005}
}
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