Analysis of Brillouin Scattering Based Fiber Optic Sensor Bonding Effects

Abstract

Brillouin scattering based sensors can measure strain and/or temperature at all points along an optical fiber; first, the fiber must be calibrated. A problem arises because the temperature coefficient of a fiber bonded to a host is changed by the host structure. Using the loose fiber coefficient could lead to large strain and temperature measurement errors. This article studies the change in the Brillouin temperature coefficient due to bonding. The intrinsic Brillouin temperature coefficient of two fibers is also found. This coefficient allows accurate strain and temperature measurements to be made, assuming the coefficient of thermal expansion of the host is known.

Temperature and strain sensing techniques using Brillouin optical time domain reflectometry

“…In general the cables with thinner coatings will induce smaller thermal strain to the fiber core compared to the jacketed cables with larger cross-sectional area 24,36 . This is demonstrated in this experiment whereby the Single-fiber and 12-ribbon fibers both have a α jacket in the range of 4×10 -6 °C -1 in comparison to the thicker coated cable like Reinforcedribbon with α jacket of about 24×10 -6 °C -1 .…”

Fiber Optic Sensing Textile for Strain Monitoring in Composite Substrates

“…With the different types of information DFOS can provide, this technology can be implemented across different industries. For example, in the area of civil engineering, DFOS can monitor structures with concrete [ 22 , 23 , 24 , 25 ] and steel [ 26 ]. For the aerospace and automobile industry, DFOS can monitor FRP components [ 27 , 28 , 29 , 30 , 31 ].…”