Banca de DEFESA: MARIANNE STELY PEIXOTO E SILVA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : MARIANNE STELY PEIXOTO E SILVA
DATE: 28/07/2023
TIME: 14:00
LOCAL: Sessão por videoconferência. Link: meet.google.com/ntv-qqud-feu
TITLE:

MULTIPARAMETER SENSORS BASED ON RAMAN ANTI-STOKES TIME DOMAIN REFLECTOMETRY IN OPTICAL FIBERS.

KEY WORDS:

Multiparameter sensor, OTDR, fiber optic sensor, distributed Raman sensor, Raman scattering.

PAGES: 183
BIG AREA: Engenharias
AREA: Engenharia Elétrica
SUMMARY:

The increasing demand for versatile detection solutions and improved measurement performance in challenging operational environments has driven extensive research in fiber optic sensors to achieve enhanced operations. A promising approach to enhancing detection systems involves considering specific aspects, such as expanding the operating range and simultaneously measuring multiple parameters, especially when these parameters are interconnected, as is the case with temperature and corrosion or temperature and refractive index. This doctoral thesis presents the enhancement of functionalities of a distributed temperature sensor based on Raman scattering (DTS-R) in optical fibers and experimentally proposes the development of a new multiparameter sensor based on time-domain anti-Stokes Raman reflectometry. The enhancement of a distributed temperature detection system through Raman scattering in optical fibers is performed, focusing on the temperature operating range. This system utilizes a commercial optical time-domain reflectometry (OTDR) equipment and amplification through erbium-doped fiber amplifiers (EDFA). The sensor's performance is experimentally evaluated over a wide temperature range, spanning from -196.15 °C to 400 °C, and over long distances, up to 27 km. Analyses are conducted using a special type of fiber with a metallic coating for high-temperature operation. The results provide information about the sensor's sensitivity, accuracy, and resolution across the wide temperature range. Additionally, the development of a new multiparameter sensor combining temperature, corrosion, and refractive index detection functionalities is presented. This sensor incorporates sensor heads designed with different optical fiber structures into the traditional DT-R for corrosion and refractive index monitoring. The sensors are tested in experiments to evaluate their response to different refractive indices, temperatures, and a controlled corrosion process, enabling the determination of the corrosion rate. The results demonstrate that the multiparameter sensor is capable of simultaneously and independently monitoring corrosion and refractive index along multiple points of the fiber link, as well as temperature in a distributed manner. This approach not only adds new functionalities to DT-R but also enhances measurement results for the analyzed parameters. The sensor's sensitivity is 0.5 dB/10-3 UIR for refractive index variations in the range of 1.3370-1.3840 UIR and 0.74 dB/nm for the detection of 100 nm aluminum corrosion deposited on the cleaved end of an optical fiber. The possible applications of the sensors in various sectors are mentioned, with emphasis on the oil and gas industry, where these sensors can contribute to enhancing the monitoring and maintenance of critical infrastructures. By integrating simultaneous measurement of multiple parameters in a single sensor, this approach offers a versatile and effective solution to meet measurement needs in challenging operational environments.

COMMITTEE MEMBERS:
Externo à Instituição - JOSÉ LUÍS FABRIS - UTFPR
Externo à Instituição - MARCELO MARTINS WERNECK - UFRJ
Interno - 1131199 - EDUARDO FONTANA
Externo à Instituição - JOAO BATISTA ROSOLEM - CPQD
Presidente - 2226204 - JOAQUIM FERREIRA MARTINS FILHO