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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 289 records · Page 16
All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

Big Data Analytics on Fiber-Optical Distributed Acoustic Sensing with Rayleigh Enhancements

his paper presents a technique to use deep neural network on data analysis of distributed acoustic sensing (DAS) system built by phase-sensitive optical time-domain reflectometry (ϕ-OTDR) with Rayleigh enhancement. Rayleigh backscattering is enhanced by ultrafast laser direct writing technique that promise the excellent sensitivity. And the use of artificial intelligence (AI) drastically improve the efficiency of data pattern recognition.

Peng, Zhaoqiang↗
DOE OSTI2019

Fiber Optic Sensor for Corrosion Monitoring in Molten Salt Irradiation Experiments

Molten salt reactors (MSRs) are one of the more promising advanced reactor concepts because they offer passive safety, high-temperature process heat, and the potential for improved fuel cycle economics through online reprocessing [1]. However, before MSRs can be reliably deployed, structural materials must be identified that can survive extended exposure to highly-corrosive salts during irradiation at high temperatures. The U.S. Department of Energy (DOE) is funding the design and eventual construction of a Versatile Test Reactor (VTR) that will include experimental facilities for testing under conditions representative of several advanced reactors, including MSRs [2]. These facilities will allow testing of candidate structural materials during irradiation with flowing salt. If properly designed, these experiments will allow for post-irradiation characterization of weight loss in the structural material coupons. However, significantly more information could be gained if the corrosion could be monitored in situ.There are currently no commercially available sensors for in situ corrosion monitoring at temperatures in the range of 500–900°C [3]. An in situ corrosion sensor would also have to survive high-dose neutron irradiation and extended exposure chemically aggressive media (e.g., molten salts). While there are ongoing efforts to use the change in magnetic susceptibility of Cr-containing alloys, this technique is limited to Cr-containing structural materials and there are concerns when using a magnetic susceptibility sensor at temperatures approaching the Curie temperature of iron (770°C) [4].

Petrie, Christian M.↗