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Title: Effects of operating pressure on flame oscillation and emission characteristics in a partially premixed swirl combustor

Abstract

The influence of varying combustor pressure on flame oscillation and emission characteristics in the partially premixed turbulent flame were investigated. In order to investigate combustion characteristics in the partially premixed turbulent flame, the combustor pressure was controlled in the range of -30 to 30 kPa for each equivalence ratio ({phi} = 0.8-1.2). The r.m.s. of the pressure fluctuations increased with decreasing combustor pressure for the lean condition. The combustor pressure had a sizeable influence on combustion oscillation, whose dominant frequency varied with the combustor pressure. Combustion instabilities could be controlled by increasing the turbulent intensity of the unburned mixture under the lean condition. An unstable flame was caused by incomplete combustion; hence, EICO greatly increased. Furthermore, EINO{sub x} simply reduced with decreasing combustor pressure at a rate of 0.035 g/10 kPa. The possibility of combustion control on the combusting mode and exhaust gas emission was demonstrated. (author)

Authors:
 [1]; ;  [2]
  1. Graduate School, Department of Mechanical Engineering, Pusan National University (Korea, Republic of)
  2. School of Mechanical Engineering, Pusan National University (Korea, Republic of)
Publication Date:
OSTI Identifier:
21390718
Resource Type:
Journal Article
Resource Relation:
Journal Name: Experimental Thermal and Fluid Science; Journal Volume: 35; Journal Issue: 1; Other Information: Elsevier Ltd. All rights reserved
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; COMBUSTION; FLAMES; OSCILLATIONS; EMISSION; COMBUSTION CONTROL; COMBUSTION INSTABILITY; FLUCTUATIONS; PRESSURE DEPENDENCE; COMBUSTORS; TURBULENCE; PRESSURE RANGE KILO PA; Combustion oscillation; Partially premixed turbulent flames

Citation Formats

Kim, Jong-Ryul, Choi, Gyung-Min, and Kim, Duck-Jool. Effects of operating pressure on flame oscillation and emission characteristics in a partially premixed swirl combustor. United States: N. p., 2011. Web. doi:10.1016/J.EXPTHERMFLUSCI.2010.08.016.
Kim, Jong-Ryul, Choi, Gyung-Min, & Kim, Duck-Jool. Effects of operating pressure on flame oscillation and emission characteristics in a partially premixed swirl combustor. United States. doi:10.1016/J.EXPTHERMFLUSCI.2010.08.016.
Kim, Jong-Ryul, Choi, Gyung-Min, and Kim, Duck-Jool. Sat . "Effects of operating pressure on flame oscillation and emission characteristics in a partially premixed swirl combustor". United States. doi:10.1016/J.EXPTHERMFLUSCI.2010.08.016.
@article{osti_21390718,
title = {Effects of operating pressure on flame oscillation and emission characteristics in a partially premixed swirl combustor},
author = {Kim, Jong-Ryul and Choi, Gyung-Min and Kim, Duck-Jool},
abstractNote = {The influence of varying combustor pressure on flame oscillation and emission characteristics in the partially premixed turbulent flame were investigated. In order to investigate combustion characteristics in the partially premixed turbulent flame, the combustor pressure was controlled in the range of -30 to 30 kPa for each equivalence ratio ({phi} = 0.8-1.2). The r.m.s. of the pressure fluctuations increased with decreasing combustor pressure for the lean condition. The combustor pressure had a sizeable influence on combustion oscillation, whose dominant frequency varied with the combustor pressure. Combustion instabilities could be controlled by increasing the turbulent intensity of the unburned mixture under the lean condition. An unstable flame was caused by incomplete combustion; hence, EICO greatly increased. Furthermore, EINO{sub x} simply reduced with decreasing combustor pressure at a rate of 0.035 g/10 kPa. The possibility of combustion control on the combusting mode and exhaust gas emission was demonstrated. (author)},
doi = {10.1016/J.EXPTHERMFLUSCI.2010.08.016},
journal = {Experimental Thermal and Fluid Science},
number = 1,
volume = 35,
place = {United States},
year = {Sat Jan 15 00:00:00 EST 2011},
month = {Sat Jan 15 00:00:00 EST 2011}
}
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