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Title: Effects of turbulence and carrier fluid on simple, turbulent spray jet flames

Abstract

This paper presents simultaneous LIF images of OH and the two-phase acetone fuel concentration as well as detailed single-point phase-Doppler measurements of velocity and droplet flux in three turbulent spray flames of acetone. This work forms part of a larger program to study spray jets and flames in a simple, well-defined geometry, aimed at providing a platform for developing and validating predictive tools for such flows. Spray flames that use nitrogen or air as droplet carrier are investigated and issues of flow field, droplet dispersion, size distribution, and evaporation are addressed. The joint OH/acetone concentration images reveal a substantial similarity to premixed flame behavior when the carrier stream is air. When the carrier is nitrogen, the reaction zone has a diffusion flame structure. There is no indication of individual droplet burning. The results show that evaporation occurs close to the jet centerline rather than in the outer shear layer. Turbulence does not have a significant impact on the evaporation rates. A small fraction of the droplets escapes the reaction zone unburned along the centerline and persists far downstream of the flame tip. The proportion of this droplet residue increases with shorter residence times as observed for the higher velocity flame.

Authors:
; ;  [1]
  1. School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, NSW 2006 (Australia)
Publication Date:
OSTI Identifier:
20681462
Resource Type:
Journal Article
Resource Relation:
Journal Name: Combustion and Flame; Journal Volume: 143; Journal Issue: 4; Other Information: Elsevier Ltd. All rights reserved
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; TURBULENCE; FLAMES; HYDROXYL RADICALS; ACETONE; VELOCITY; DROPLETS; MOTION; PARTICLE SIZE; EVAPORATION; IMAGES

Citation Formats

Staarner, Sten H., Gounder, James, and Masri, Assaad R. Effects of turbulence and carrier fluid on simple, turbulent spray jet flames. United States: N. p., 2005. Web. doi:10.1016/j.combustflame.2005.08.016.
Staarner, Sten H., Gounder, James, & Masri, Assaad R. Effects of turbulence and carrier fluid on simple, turbulent spray jet flames. United States. doi:10.1016/j.combustflame.2005.08.016.
Staarner, Sten H., Gounder, James, and Masri, Assaad R. Thu . "Effects of turbulence and carrier fluid on simple, turbulent spray jet flames". United States. doi:10.1016/j.combustflame.2005.08.016.
@article{osti_20681462,
title = {Effects of turbulence and carrier fluid on simple, turbulent spray jet flames},
author = {Staarner, Sten H. and Gounder, James and Masri, Assaad R.},
abstractNote = {This paper presents simultaneous LIF images of OH and the two-phase acetone fuel concentration as well as detailed single-point phase-Doppler measurements of velocity and droplet flux in three turbulent spray flames of acetone. This work forms part of a larger program to study spray jets and flames in a simple, well-defined geometry, aimed at providing a platform for developing and validating predictive tools for such flows. Spray flames that use nitrogen or air as droplet carrier are investigated and issues of flow field, droplet dispersion, size distribution, and evaporation are addressed. The joint OH/acetone concentration images reveal a substantial similarity to premixed flame behavior when the carrier stream is air. When the carrier is nitrogen, the reaction zone has a diffusion flame structure. There is no indication of individual droplet burning. The results show that evaporation occurs close to the jet centerline rather than in the outer shear layer. Turbulence does not have a significant impact on the evaporation rates. A small fraction of the droplets escapes the reaction zone unburned along the centerline and persists far downstream of the flame tip. The proportion of this droplet residue increases with shorter residence times as observed for the higher velocity flame.},
doi = {10.1016/j.combustflame.2005.08.016},
journal = {Combustion and Flame},
number = 4,
volume = 143,
place = {United States},
year = {Thu Dec 01 00:00:00 EST 2005},
month = {Thu Dec 01 00:00:00 EST 2005}
}
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