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Title: Combustion Control and Diagnostics Sensor Testing in a Thermal Barrier Coated Combustor

Abstract

The combustion control and diagnostics sensor (CCADS) continues to be developed as an in-situ combustion sensor, with immediate application to natural gas fired turbines. In-situ combustion monitoring is also expected to benefit advanced power plants of the future, fueled by coal-derived syngas, liquified natural gas (LNG), hydrogen, or hydrogen blend fuels. The in-situ monitoring that CCADS provides can enable the optimal operation of advanced, fuel-flexible turbines for minimal pollutant emissions and maximum efficiency over the full operating range of an advanced turbine. Previous work has demonstrated CCADS as a useful sensor for in-situ monitoring of natural gas combustion, including detection of important combustion events such as flashback and lean blowoff, in experimental combustors without thermal barrier coatings (TBC). Since typical TBC materials are electrical insulators at room temperature, and CCADS operation requires conduction of electrical current to the walls of the combustor, a TBC on the combustion liner was identified as a potential barrier to CCADS operation in commercial application. This paper reports on CCADS experiments in a turbulent lean premixed combustor with a yttria-stabilized zirconia (YSZ) thermal barrier coating on the combustor wall. The tests were conducted at 0.1 MPa (1 atm), with a 15V excitation voltage on themore » CCADS electrodes. The results confirm that for a typical thermal barrier coating, CCADS operates properly, and the total measured average resistance is close to that of an uncoated combustor. This result is consistent with previous materials studies that found the electrical resistance of typical TBC materials considerably decreases at combustor operating temperatures.« less

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:
915397
Report Number(s):
DOE/NETL-IR-2007-135
DOE Contract Number:
None cited
Resource Type:
Conference
Resource Relation:
Conference: ASME Turbo Expo 2007, Montreal, Canada, May 14-17, 2007
Country of Publication:
United States
Language:
English

Citation Formats

Chorpening, B.T., Dukes, M.G., Robey, E.H., and Thornton, J.D.. Combustion Control and Diagnostics Sensor Testing in a Thermal Barrier Coated Combustor. United States: N. p., 2007. Web.
Chorpening, B.T., Dukes, M.G., Robey, E.H., & Thornton, J.D.. Combustion Control and Diagnostics Sensor Testing in a Thermal Barrier Coated Combustor. United States.
Chorpening, B.T., Dukes, M.G., Robey, E.H., and Thornton, J.D.. Tue . "Combustion Control and Diagnostics Sensor Testing in a Thermal Barrier Coated Combustor". United States. doi:. https://www.osti.gov/servlets/purl/915397.
@article{osti_915397,
title = {Combustion Control and Diagnostics Sensor Testing in a Thermal Barrier Coated Combustor},
author = {Chorpening, B.T. and Dukes, M.G. and Robey, E.H. and Thornton, J.D.},
abstractNote = {The combustion control and diagnostics sensor (CCADS) continues to be developed as an in-situ combustion sensor, with immediate application to natural gas fired turbines. In-situ combustion monitoring is also expected to benefit advanced power plants of the future, fueled by coal-derived syngas, liquified natural gas (LNG), hydrogen, or hydrogen blend fuels. The in-situ monitoring that CCADS provides can enable the optimal operation of advanced, fuel-flexible turbines for minimal pollutant emissions and maximum efficiency over the full operating range of an advanced turbine. Previous work has demonstrated CCADS as a useful sensor for in-situ monitoring of natural gas combustion, including detection of important combustion events such as flashback and lean blowoff, in experimental combustors without thermal barrier coatings (TBC). Since typical TBC materials are electrical insulators at room temperature, and CCADS operation requires conduction of electrical current to the walls of the combustor, a TBC on the combustion liner was identified as a potential barrier to CCADS operation in commercial application. This paper reports on CCADS experiments in a turbulent lean premixed combustor with a yttria-stabilized zirconia (YSZ) thermal barrier coating on the combustor wall. The tests were conducted at 0.1 MPa (1 atm), with a 15V excitation voltage on the CCADS electrodes. The results confirm that for a typical thermal barrier coating, CCADS operates properly, and the total measured average resistance is close to that of an uncoated combustor. This result is consistent with previous materials studies that found the electrical resistance of typical TBC materials considerably decreases at combustor operating temperatures.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue May 01 00:00:00 EDT 2007},
month = {Tue May 01 00:00:00 EDT 2007}
}

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