Pilot-premix flames

Higher operational flexibility in gas turbines without NOx increase

verfasst von: Peter Albrecht, Stefanie Bade, Christian Oliver Paschereit, Friedrich Dinkelacker, Ephraim Gutmark
Abstract: A premixed pilot injection with reduced NO_x formation is proposed as a fail-safe and simple control method to extend the operating range of gas turbines. Different pilot locations within the combustion chamber were chosen to see the impact of pilot injection flames on the local extinction behavior and on the NO_x formation. The pilot flame injector (PFI) represents a device for premixed pilot injection and was located in the center of the swirl burner cone. Moreover, the premixed pilot could be ignited by an embedded spark plug inside the PFI so that the main flame, especially near the lean limit, can be provided with additional radicals at the lower stagnation point of the central recirculation zone. A second pilot injection was located at the combustor dump to inject the pilot fuel/air mixture axially into the shear layer between the central and side recirculation zone. It could be shown for different main air preheat temperatures and with activated PFI flame (at 110 Hz spark frequency), that the premixed pilot is the most efficient control method for local extinction prevention without CO emission increase. Also the NO _x emissions keep on similar level as the baseline case. The spark plug might also be replaced by a laser ignition device. The efficiency of laser spark plugs could be already demonstrated under atmospheric conditions in Moesl2008 [1] where different ignition devices are proposed to ignite a swirl-stabilized kerosine mixture. Moreover, former tests with the PFI flame indicate also a method to control instabilities so that high amplitude of p' oscillations could be suppressed.
Externe Organisation(en): Technische Universität Berlin
Universität Siegen
University of Cincinnati
Typ: Aufsatz in Konferenzband
Seiten: 125-135
Anzahl der Seiten: 11
Publikationsdatum: 2009
Publikationsstatus: Veröffentlicht
Peer-reviewed: Ja
ASJC Scopus Sachgebiete: Allgemeiner Maschinenbau
Elektronische Version(en): https://doi.org/10.1115/GT2009-59181 (Zugang: Unbekannt)

BibTeX

@inproceedings{e11c4afe21d54cdeb08f27bc4a034fff,
title = "Pilot-premix flames: Higher operational flexibility in gas turbines without NOx increase",
abstract = "A premixed pilot injection with reduced NOx formation is proposed as a fail-safe and simple control method to extend the operating range of gas turbines. Different pilot locations within the combustion chamber were chosen to see the impact of pilot injection flames on the local extinction behavior and on the NOx formation. The pilot flame injector (PFI) represents a device for premixed pilot injection and was located in the center of the swirl burner cone. Moreover, the premixed pilot could be ignited by an embedded spark plug inside the PFI so that the main flame, especially near the lean limit, can be provided with additional radicals at the lower stagnation point of the central recirculation zone. A second pilot injection was located at the combustor dump to inject the pilot fuel/air mixture axially into the shear layer between the central and side recirculation zone. It could be shown for different main air preheat temperatures and with activated PFI flame (at 110 Hz spark frequency), that the premixed pilot is the most efficient control method for local extinction prevention without CO emission increase. Also the NO x emissions keep on similar level as the baseline case. The spark plug might also be replaced by a laser ignition device. The efficiency of laser spark plugs could be already demonstrated under atmospheric conditions in Moesl2008 [1] where different ignition devices are proposed to ignite a swirl-stabilized kerosine mixture. Moreover, former tests with the PFI flame indicate also a method to control instabilities so that high amplitude of p' oscillations could be suppressed.",
author = "Peter Albrecht and Stefanie Bade and Paschereit, {Christian Oliver} and Friedrich Dinkelacker and Ephraim Gutmark",
year = "2009",
doi = "10.1115/GT2009-59181",
language = "English",
isbn = "9780791848838",
series = "Proceedings of the ASME Turbo Expo",
pages = "125--135",
booktitle = "Proceedings of the ASME Turbo Expo 2009",
note = "2009 ASME Turbo Expo ; Conference date: 08-06-2009 Through 12-06-2009",
}