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Title: Impact of Fuel Interchangeability on dynamic Instabilities in Gas Turbine Engines

Abstract

Modern, low NOx emitting gas turbines typically utilize lean pre-mixed (LPM) combustion as a means of achieving target emissions goals. As stable combustion in LPM systems is somewhat intolerant to changes in operating conditions, precise engine tuning on a prescribed range of fuel properties is commonly performed to avoid dynamic instabilities. This has raised concerns regarding the use of imported liquefied natural gas (LNG) and natural gas liquids (NGL’s) to offset a reduction in the domestic natural gas supply, which when introduced into the pipeline could alter the fuel BTU content and subsequently exacerbate problems such as combustion instabilities. The intent of this study is to investigate the sensitivity of dynamically unstable test rigs to changes in fuel composition and heat content. Fuel Wobbe number was controlled by blending methane and natural gas with various amounts of ethane, propane and nitrogen. Changes in combustion instabilities were observed, in both atmospheric and pressurized test rigs, for fuels containing high concentrations of propane (> 62% by vol). However, pressure oscillations measured while operating on typical “LNG like” fuels did not appear to deviate significantly from natural gas and methane flame responses. Mechanisms thought to produce changes in the dynamic response are discussed.

Authors:
; ; ;
Publication Date:
Research Org.:
National Energy Technology Laboratory (NETL), Pittsburgh, PA, and Morgantown, WV
Sponsoring Org.:
USDOE - Office of Fossil Energy (FE)
OSTI Identifier:
913267
Report Number(s):
DOE/NETL-IR-2007-102
TRN: US200802%%733
DOE Contract Number:
None cited
Resource Type:
Conference
Resource Relation:
Conference: 5th U.S. National Combustion Meeting, San Diego, CA, Mar. 25-28, 2007
Country of Publication:
United States
Language:
English
Subject:
03 NATURAL GAS; CALORIFIC VALUE; COMBUSTION; ENGINES; ETHANE; GAS TURBINE ENGINES; GAS TURBINES; INTERCHANGEABILITY; LIQUEFIED NATURAL GAS; METHANE; NATURAL GAS; NATURAL GAS LIQUIDS; NITROGEN; OSCILLATIONS; PIPELINES; PROPANE; TARGETS; TUNING; fuel composition; liquified natural gas; lean pre-mixed systems; propane; methane

Citation Formats

Ferguson, D.H., Straub, D.L., Richards, G.A., and Robey, E.H. Impact of Fuel Interchangeability on dynamic Instabilities in Gas Turbine Engines. United States: N. p., 2007. Web.
Ferguson, D.H., Straub, D.L., Richards, G.A., & Robey, E.H. Impact of Fuel Interchangeability on dynamic Instabilities in Gas Turbine Engines. United States.
Ferguson, D.H., Straub, D.L., Richards, G.A., and Robey, E.H. Thu . "Impact of Fuel Interchangeability on dynamic Instabilities in Gas Turbine Engines". United States. doi:. https://www.osti.gov/servlets/purl/913267.
@article{osti_913267,
title = {Impact of Fuel Interchangeability on dynamic Instabilities in Gas Turbine Engines},
author = {Ferguson, D.H. and Straub, D.L. and Richards, G.A. and Robey, E.H.},
abstractNote = {Modern, low NOx emitting gas turbines typically utilize lean pre-mixed (LPM) combustion as a means of achieving target emissions goals. As stable combustion in LPM systems is somewhat intolerant to changes in operating conditions, precise engine tuning on a prescribed range of fuel properties is commonly performed to avoid dynamic instabilities. This has raised concerns regarding the use of imported liquefied natural gas (LNG) and natural gas liquids (NGL’s) to offset a reduction in the domestic natural gas supply, which when introduced into the pipeline could alter the fuel BTU content and subsequently exacerbate problems such as combustion instabilities. The intent of this study is to investigate the sensitivity of dynamically unstable test rigs to changes in fuel composition and heat content. Fuel Wobbe number was controlled by blending methane and natural gas with various amounts of ethane, propane and nitrogen. Changes in combustion instabilities were observed, in both atmospheric and pressurized test rigs, for fuels containing high concentrations of propane (> 62% by vol). However, pressure oscillations measured while operating on typical “LNG like” fuels did not appear to deviate significantly from natural gas and methane flame responses. Mechanisms thought to produce changes in the dynamic response are discussed.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Mar 01 00:00:00 EST 2007},
month = {Thu Mar 01 00:00:00 EST 2007}
}

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