Skip to main content Accessibility help
×
Home
Hostname: page-component-65dc7cd545-fz4lj Total loading time: 0.198 Render date: 2021-07-25T14:16:16.982Z Has data issue: true Feature Flags: { "shouldUseShareProductTool": true, "shouldUseHypothesis": true, "isUnsiloEnabled": true, "metricsAbstractViews": false, "figures": true, "newCiteModal": false, "newCitedByModal": true, "newEcommerce": true, "newUsageEvents": true }

Article contents

Failure Mechanisms of Fiber Optic Temperature Sensors in High Temperature and Vibration Environments

Published online by Cambridge University Press:  15 July 2016

Loucas Tsakalakos
Affiliation:
GE Global Research, Niskayuna, New York, United States.
Uttara A. Dani
Affiliation:
GE Global Research, Niskayuna, New York, United States.
Boon K. Lee
Affiliation:
GE Global Research, Niskayuna, New York, United States.
Susanne M. Lee
Affiliation:
GE Global Research, Niskayuna, New York, United States.
Sudeep Mandal
Affiliation:
GE Global Research, Niskayuna, New York, United States.
Vincent Smentkowski
Affiliation:
GE Global Research, Niskayuna, New York, United States.
Sunilkumar Soni
Affiliation:
GE Global Research, Niskayuna, New York, United States.
Corresponding
E-mail address:
Get access

Abstract

Fiber optic temperature sensors are used in a variety of harsh environment applications. We have explored use of such temperature sensors in commercial gas turbines to measure the temperature at various regions of interest within the turbine system. More specifically, fiber optic temperature rakes were designed and installed on a commercial gas turbine under full load conditions. This work will focus on failure mechanisms observed at multiple length scales that impact the performance of high temperature optical fiber sensors. It was found that Au-coated silica fibers, which are a standard in the industry, undergo various failure modes when subjected to combinations of high temperature and high vibration. More specifically, the Au coating became soft/ductile as the temperature is increased. We also observed that the Au coating was not well bonded to the silica fiber, as expected since there were no adhesion layers present. These effects led to significant damage of the fiber optic under high vibrations. We also found that vibrations from the gas turbine coupled into fundamental modes of the fiber optic probe assembly, which were analyzed by detailed dynamic mechanical analysis. This led to the fiber impacting the internal wall of the probe assembly, which caused further damage and failure of the fiber and the Au coating. The silica fibers returned from the field also exhibited significant twisting throughout most of their length. This suggests the fibers reached temperatures above their strain point (about 1000 C for pure silica glass), which is explained by either a) the strain point had been significantly reduced by the presence of the Ge dopant, or b) the temperature was higher than expected in the gas turbine exhaust region. It was also hypothesized that complex anelastic effects may play a role under the high temperature, high vibration environment experienced by the probes. Detailed structural analysis of the fiber optic temperature sensors by scanning electron microscopy, ToF-SIMS, and X-ray microscopy will be presented to corroborate the above simulations and proposed damage mechanisms. Finally, we note that the fiber Bragg gratings (FBG) present within the temperature probes provided promising temperature data, and were in fact not damaged/erased by the high temperature environment.

Type
Articles
Copyright
Copyright © Materials Research Society 2016 

Access options

Get access to the full version of this content by using one of the access options below.

References

Xia, Hua, Byrd, Doug, Dekate, Sachin, and Lee, Boon, “High-Density Fiber Optical Sensor and Instrumentation for Gas Turbine Operation Condition Monitoring,” Journal of Sensors, vol. 2013, Article ID 206738, 10 pages, 2013. doi:10.1155/2013/206738 CrossRefGoogle Scholar
Glaesemann, G.S., Optical Fiber Failure Probability Predictions from Long Length Strength Distributions, Proc. 40th International Wire and Cable Symposium, 819–825 (1991).
Shand, E.B, Engineering Glasses, IN Modern Materials, Vol. 6, Academic Press, New York, 1968, p. 262.Google Scholar

Send article to Kindle

To send this article to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about sending to your Kindle. Find out more about sending to your Kindle.

Note you can select to send to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

Find out more about the Kindle Personal Document Service.

Failure Mechanisms of Fiber Optic Temperature Sensors in High Temperature and Vibration Environments
Available formats
×

Send article to Dropbox

To send this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Dropbox.

Failure Mechanisms of Fiber Optic Temperature Sensors in High Temperature and Vibration Environments
Available formats
×

Send article to Google Drive

To send this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Google Drive.

Failure Mechanisms of Fiber Optic Temperature Sensors in High Temperature and Vibration Environments
Available formats
×
×

Reply to: Submit a response

Please enter your response.

Your details

Please enter a valid email address.

Conflicting interests

Do you have any conflicting interests? *