Cargando…

Synchronous Vibration Measurements for Shrouded Blades Based on Fiber Optical Sensors with Lenses in a Steam Turbine

It is important to obtain accurate dynamic vibrations of steam turbine blades for safe operation. Strain gauge (SG) measurements cannot fully obtain vibrations of all blades and nodal diameter (ND) details. The blade tip timing (BTT) technique could resolve this problem because it has the advantage...

Descripción completa

Detalles Bibliográficos
Autores principales: Ye, Dechao, Duan, Fajie, Jiang, Jiajia, Cheng, Zhonghai, Niu, Guangyue, Shan, Peng, Zhang, Jiamin
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2019
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6603571/
https://www.ncbi.nlm.nih.gov/pubmed/31159268
http://dx.doi.org/10.3390/s19112501
_version_ 1783431535845703680
author Ye, Dechao
Duan, Fajie
Jiang, Jiajia
Cheng, Zhonghai
Niu, Guangyue
Shan, Peng
Zhang, Jiamin
author_facet Ye, Dechao
Duan, Fajie
Jiang, Jiajia
Cheng, Zhonghai
Niu, Guangyue
Shan, Peng
Zhang, Jiamin
author_sort Ye, Dechao
collection PubMed
description It is important to obtain accurate dynamic vibrations of steam turbine blades for safe operation. Strain gauge (SG) measurements cannot fully obtain vibrations of all blades and nodal diameter (ND) details. The blade tip timing (BTT) technique could resolve this problem because it has the advantage of measuring all blades’ vibrations. This article proposed an improved BTT technique for measuring synchronous vibrations of shrouded blades in a steam turbine based on fiber optical sensors with lenses. The newly developed sensor was equipped with a Plano-convex lens, and the optical path was specifically designed to collimate the beam within a large working distance from 4 to 19 mm and improve the measuring accuracy. A method to search the spectra of all peak vibration amplitudes of all the blades was proposed to obtain the ND details of synchronous vibration. Experimental results validated the efficiency and accuracy of the proposed methods and sensors. Comparison results of BTT measurements with SG measurements showed that the relative errors of normalized frequency and strain were small and acceptable.
format Online
Article
Text
id pubmed-6603571
institution National Center for Biotechnology Information
language English
publishDate 2019
publisher MDPI
record_format MEDLINE/PubMed
spelling pubmed-66035712019-07-17 Synchronous Vibration Measurements for Shrouded Blades Based on Fiber Optical Sensors with Lenses in a Steam Turbine Ye, Dechao Duan, Fajie Jiang, Jiajia Cheng, Zhonghai Niu, Guangyue Shan, Peng Zhang, Jiamin Sensors (Basel) Article It is important to obtain accurate dynamic vibrations of steam turbine blades for safe operation. Strain gauge (SG) measurements cannot fully obtain vibrations of all blades and nodal diameter (ND) details. The blade tip timing (BTT) technique could resolve this problem because it has the advantage of measuring all blades’ vibrations. This article proposed an improved BTT technique for measuring synchronous vibrations of shrouded blades in a steam turbine based on fiber optical sensors with lenses. The newly developed sensor was equipped with a Plano-convex lens, and the optical path was specifically designed to collimate the beam within a large working distance from 4 to 19 mm and improve the measuring accuracy. A method to search the spectra of all peak vibration amplitudes of all the blades was proposed to obtain the ND details of synchronous vibration. Experimental results validated the efficiency and accuracy of the proposed methods and sensors. Comparison results of BTT measurements with SG measurements showed that the relative errors of normalized frequency and strain were small and acceptable. MDPI 2019-05-31 /pmc/articles/PMC6603571/ /pubmed/31159268 http://dx.doi.org/10.3390/s19112501 Text en © 2019 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Ye, Dechao
Duan, Fajie
Jiang, Jiajia
Cheng, Zhonghai
Niu, Guangyue
Shan, Peng
Zhang, Jiamin
Synchronous Vibration Measurements for Shrouded Blades Based on Fiber Optical Sensors with Lenses in a Steam Turbine
title Synchronous Vibration Measurements for Shrouded Blades Based on Fiber Optical Sensors with Lenses in a Steam Turbine
title_full Synchronous Vibration Measurements for Shrouded Blades Based on Fiber Optical Sensors with Lenses in a Steam Turbine
title_fullStr Synchronous Vibration Measurements for Shrouded Blades Based on Fiber Optical Sensors with Lenses in a Steam Turbine
title_full_unstemmed Synchronous Vibration Measurements for Shrouded Blades Based on Fiber Optical Sensors with Lenses in a Steam Turbine
title_short Synchronous Vibration Measurements for Shrouded Blades Based on Fiber Optical Sensors with Lenses in a Steam Turbine
title_sort synchronous vibration measurements for shrouded blades based on fiber optical sensors with lenses in a steam turbine
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6603571/
https://www.ncbi.nlm.nih.gov/pubmed/31159268
http://dx.doi.org/10.3390/s19112501
work_keys_str_mv AT yedechao synchronousvibrationmeasurementsforshroudedbladesbasedonfiberopticalsensorswithlensesinasteamturbine
AT duanfajie synchronousvibrationmeasurementsforshroudedbladesbasedonfiberopticalsensorswithlensesinasteamturbine
AT jiangjiajia synchronousvibrationmeasurementsforshroudedbladesbasedonfiberopticalsensorswithlensesinasteamturbine
AT chengzhonghai synchronousvibrationmeasurementsforshroudedbladesbasedonfiberopticalsensorswithlensesinasteamturbine
AT niuguangyue synchronousvibrationmeasurementsforshroudedbladesbasedonfiberopticalsensorswithlensesinasteamturbine
AT shanpeng synchronousvibrationmeasurementsforshroudedbladesbasedonfiberopticalsensorswithlensesinasteamturbine
AT zhangjiamin synchronousvibrationmeasurementsforshroudedbladesbasedonfiberopticalsensorswithlensesinasteamturbine