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DOE OSTI · 3030772

HDG-1 Fiber Bragg grating data analysis

Payne, Charles Nelson [Idaho National Laboratory (INL), Idaho Falls, ID (United States)]·Fleming, Austin D. [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000268015028)·McCary, Kelly M. [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000341308856)
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Abstract

The main goal of the High dose graphite 1 Advanced test reactor experiment was to study nuclear grade graphite at high fluences. Additional supplementary optical fiber instrumentation was added to this long duration experiment for instrumentation development purposes. The supplementary instrumentation consisted of two pure silica core, fluorine doped cladding optical fibers each etched with 9 fiber Bragg gratings, one fiber being heat treated for 9 hours at 750 C and 16 hours at 750 C, the other being heat treated for 24 hours at 550 C and 48 hours at 650 C. Fiber Bragg gratings are known to have issues of measurement drift when in high temperature and high radiation environments like what is encountered in the Advanced test reactor. At the culmination of this experiment, the optical fibers saw ~1.3E21 n/cm2 total fluence, which is at the highest fluences that fiber Bragg gratings have been studied to date. Reported here is the analysis of this data including radiation induced shift and changes in sensitivity.

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Payne, Charles Nelson [Idaho National Laboratory (INL), Idaho Falls, ID (United States)], Fleming, Austin D. [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000268015028), McCary, Kelly M. [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000341308856). 2025-05-29. HDG-1 Fiber Bragg grating data analysis. https://doi.org/10.2172/3030772

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