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Title: LES of an ignition sequence in a gas turbine engine

Abstract

Being able to ignite or reignite a gas turbine engine in a cold and rarefied atmosphere is a critical issue for many manufacturers. From a fundamental point of view, the ignition of the first burner and the flame propagation from one burner to another are phenomena that are usually not studied. The present work is a large eddy simulation (LES) of these phenomena. To simulate a complete ignition sequence in an annular chamber, LES has been applied to the full 360 geometry, including 18 burners. This geometry corresponds to a real gas turbine chamber. Massively parallel computing (700 processors on a Cray XT3 machine) was essential to perform such a large calculation. Results show that liquid fuel injection has a strong influence on the ignition times. Moreover, the rate of flame progress from burner to burner is much higher than the turbulent flame speed due to a major effect of thermal expansion. This flame speed is also strongly modified by the main burner aerodynamics due to the swirled injection. Finally, the variability of the combustor sectors and quadrant ignition times is highlighted. (author)

Authors:
; ;  [1];  [2];  [3]
  1. CERFACS, Toulouse (France)
  2. IMFT - CNRS, Toulouse (France)
  3. Turbomeca (SAFRAN group), Bordes (France)
Publication Date:
OSTI Identifier:
21044869
Resource Type:
Journal Article
Resource Relation:
Journal Name: Combustion and Flame; Journal Volume: 154; Journal Issue: 1-2; Other Information: Elsevier Ltd. All rights reserved
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; GAS TURBINE ENGINES; IGNITION; INJECTION; AERODYNAMICS; COMBUSTION; LIQUID FUELS; THERMAL EXPANSION; TWO-PHASE FLOW; SIMULATION; VELOCITY; FLAME PROPAGATION; VORTEX FLOW; Turbulent combustion; Large eddy simulation; Euler-Euler approach

Citation Formats

Boileau, M., Staffelbach, G., Cuenot, B., Poinsot, T., and Berat, C. LES of an ignition sequence in a gas turbine engine. United States: N. p., 2008. Web. doi:10.1016/J.COMBUSTFLAME.2008.02.006.
Boileau, M., Staffelbach, G., Cuenot, B., Poinsot, T., & Berat, C. LES of an ignition sequence in a gas turbine engine. United States. doi:10.1016/J.COMBUSTFLAME.2008.02.006.
Boileau, M., Staffelbach, G., Cuenot, B., Poinsot, T., and Berat, C. Tue . "LES of an ignition sequence in a gas turbine engine". United States. doi:10.1016/J.COMBUSTFLAME.2008.02.006.
@article{osti_21044869,
title = {LES of an ignition sequence in a gas turbine engine},
author = {Boileau, M. and Staffelbach, G. and Cuenot, B. and Poinsot, T. and Berat, C.},
abstractNote = {Being able to ignite or reignite a gas turbine engine in a cold and rarefied atmosphere is a critical issue for many manufacturers. From a fundamental point of view, the ignition of the first burner and the flame propagation from one burner to another are phenomena that are usually not studied. The present work is a large eddy simulation (LES) of these phenomena. To simulate a complete ignition sequence in an annular chamber, LES has been applied to the full 360 geometry, including 18 burners. This geometry corresponds to a real gas turbine chamber. Massively parallel computing (700 processors on a Cray XT3 machine) was essential to perform such a large calculation. Results show that liquid fuel injection has a strong influence on the ignition times. Moreover, the rate of flame progress from burner to burner is much higher than the turbulent flame speed due to a major effect of thermal expansion. This flame speed is also strongly modified by the main burner aerodynamics due to the swirled injection. Finally, the variability of the combustor sectors and quadrant ignition times is highlighted. (author)},
doi = {10.1016/J.COMBUSTFLAME.2008.02.006},
journal = {Combustion and Flame},
number = 1-2,
volume = 154,
place = {United States},
year = {Tue Jul 15 00:00:00 EDT 2008},
month = {Tue Jul 15 00:00:00 EDT 2008}
}
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