Fiber optic hot-wire flowmeter based on a metallic coated hybrid long period grating/fiber Bragg grating structure

• Type: Article in International Scientific Journal
• Date: 2011

Authors

Paulo Caldas (Author) Other; Pedro A S Jorge (Author) FCUP; Gaspar Rego (Author) FCUP; Orlando Frazao (Author) FCUP; Jose Luis Santos (Author) FCUP; Luis Alberto Ferreira (Author) Other; Francisco Araujo (Author) Other

Journal

Title: Applied Optics

Vol. 50

Pages: 2738-2743

ISSN: 1559-128X

Publisher: Optical Society of America

Indexing

ISI Web of Knowledge - 73 Citations

Scopus - 78 Citations

Scientific classification

FOS: Natural sciences > Physical sciences

Other information

Authenticus ID: P-002-QGM

DOI: 10.1364/ao.50.002738

Abstract (EN): In this work an all-optical hot-wire flowmeter based on a silver coated fiber combining a long period grating and a fiber Bragg grating (FBG) structure is proposed. Light from a pump laser at 1480nm propagating down the fiber is coupled by the long period grating into the fiber cladding and is absorbed by the silver coating deposited on the fiber surface over the Bragg grating structure. This absorption acts like a hot wire raising the fiber temperature locally, which is effectively detected by the FBG resonance shift. The temperature increase depends on the flow speed of the surrounding air, which has the effect of cooling the fiber. It is demonstrated that the Bragg wavelength shift can be related to the flow speed. A flow speed resolution of 0.08m/s is achieved using this new configuration. (C) 2011 Optical Society of America

Language: English

Type (Professor's evaluation): Scientific