Open AccessFiber-coupled LWIR hyperspectral sensor suite for non-contact component surface temperature measurements
Author(s) -
Paul S. Hsu,
Keith D. Rein,
Oleksandr Bibik,
David Wu,
Timothy S. Cook,
Subodh Adhikari,
Benjamin Emerson,
Tim Lieuwen,
James R. Gord,
Sukesh Roy
Publication year - 2018
Publication title -
applied optics
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 0.668
H-Index - 197
eISSN - 2155-3165
pISSN - 1559-128X
DOI - 10.1364/ao.57.010418
Subject(s) - materials science , optics , optical fiber , fiber optic sensor , optoelectronics , fiber , composite material , physics
We report on the development of a robust fiber-coupled long-wavelength infrared (LWIR) hyperspectral sensor suite for accurate and reliable non-contact surface temperature measurements in propulsion systems with limited optical access. We first experimentally investigate various state-of-the-art LWIR optical fibers and identify the ideal fiber for efficient coupling and transmission of LWIR signals. The effects of the fiber material, structure, bending, and thermal heating on LWIR fiber transmission are characterized. Subsequently, we discuss the development of a fiber-coupled LWIR hyperspectral sensor using a multi-mode polycrystalline fiber. The temperature measurement accuracy and precision of the sensor are determined using a well-calibrated blackbody radiation source and heated thermal barrier coating. The sensor is integrated into a homemade water-cooled probe housing and environmental protection box and subsequently used for reliable combustor liner temperature measurements in a high-pressure, liquid-fueled combustor rig with no built-in optical access. We also discuss the measurement challenges associated with flame interference and potential solutions. The LWIR sensor shows significant promise in its application to surface temperature measurements, and our findings can aid propulsion system engineers and researchers in system design and operation optimization.