We report a distributed fiber-optic pressure sensor based on Bourdon tubes using Rayleigh backscattering metered by optical frequency-domain reflectometry (OFDR). In the proposed sensor, a piece of single-mode fiber (SMF) is attached to the concave surfaces of Bourdon tubes using a thin layer of epoxy. The strain profiles along the concave surface of the Bourdon tube vary with applied pressure, and the strain variations are transferred to the attached SMF through the epoxy layer, resulting in spectral shifts in the local Rayleigh backscattering signals. By monitoring the local spectral shifts of the OFDR system, the pressure applied to the Bourdon tube can be determined. By cascading multiple Bourdon tubes and correspondingly attaching SMF sections (i.e., a series of SMF-modified Bourdon tubes), distributed pressure measurements can be realized. Three Bourdon tubes are employed to demonstrate the proposed spatially distributed sensing scheme. The experimental results showed that linear relationships between spectral shift and pressure were obtained in all three SMF-Bourdon tubes (i.e., at three spatial locations). It is expected that the proposed sensing device, the SMF-Bourdon tube, can be used in applications where distributed/multipoint pressure measurements are needed.
C. Zhu et al., "Distributed Fiber-Optic Pressure Sensor based on Bourdon Tubes Metered by Optical Frequency-Domain Reflectometry," Optical Engineering, vol. 58, no. 7, SPIE, Jul 2019.
The definitive version is available at https://doi.org/10.1117/1.OE.58.7.072010
Electrical and Computer Engineering
Intelligent Systems Center
Keywords and Phrases
Backscattering; Fiber optic sensors; Fiber optics; Fibers; Frequency domain analysis; Natural frequencies; Optical materials; Pressure measurement; Pressure sensors; Rayleigh scattering; Reflection; Reflectometers; Single mode fibers; Applied pressure; Bourdon tubes; Distributed sensing; Fiber optic pressure sensor; Linear relationships; Optical frequency domain reflectometry; Rayleigh backscattering; Strain variation; Tubes (components); Distributed pressure sensor; Single-mode fiber
International Standard Serial Number (ISSN)
Article - Journal
© 2019 SPIE, All rights reserved.
01 Jul 2019