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Title: Distributed temperature sensing inside a 19-rod bundle

Abstract

The temperature field within a model of a sodium-cooled fast reactor fuel rod bundle was measured using Ø155 μm fiber optic distributed temperature sensors (DTS). The bundle consists of 19 electrically-heated rods Ø6.3 mm and 865 mm long. Working fluids were argon and air at atmospheric pressure and Reynolds numbers up to 300. A 20 m-long DTS was threaded through Ø1 mm capillaries wound around rods as wire-wraps. The sensor generated 173 measurements along each rod at 5 mm resolution for a total of 3300 data locations. A second DTS, 58 m long, was suspended between rods to provide 9300 fluid temperature measurements at 20 mm resolution. Such data density makes it possible to construct 3D maps of the temperature field that are beyond the reach of traditional sensors such as thermocouples. This is illustrated through a series of steady-state and transient tests. As a result, the work demonstrates the feasibility of mapping temperature within the close confines of a rod bundle at resolutions suitable for validation of computational fluid dynamics codes.

Authors:
 [1];  [1];  [1]
  1. Argonne National Lab. (ANL), Lemont, IL (United States)
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
U.S. DOE Chicago Operations Office; USDOE
OSTI Identifier:
1379175
Grant/Contract Number:
AC02-06CH11357
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Nuclear Engineering and Design
Additional Journal Information:
Journal Volume: 319; Journal Issue: C; Journal ID: ISSN 0029-5493
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS; 22 GENERAL STUDIES OF NUCLEAR REACTORS; Fiber optic distributed temperature sensor; Nuclear fuel rod bundle

Citation Formats

Lomperski, S., Bremer, N., and Gerardi, C. Distributed temperature sensing inside a 19-rod bundle. United States: N. p., 2017. Web. doi:10.1016/j.nucengdes.2017.05.008.
Lomperski, S., Bremer, N., & Gerardi, C. Distributed temperature sensing inside a 19-rod bundle. United States. doi:10.1016/j.nucengdes.2017.05.008.
Lomperski, S., Bremer, N., and Gerardi, C. 2017. "Distributed temperature sensing inside a 19-rod bundle". United States. doi:10.1016/j.nucengdes.2017.05.008.
@article{osti_1379175,
title = {Distributed temperature sensing inside a 19-rod bundle},
author = {Lomperski, S. and Bremer, N. and Gerardi, C.},
abstractNote = {The temperature field within a model of a sodium-cooled fast reactor fuel rod bundle was measured using Ø155 μm fiber optic distributed temperature sensors (DTS). The bundle consists of 19 electrically-heated rods Ø6.3 mm and 865 mm long. Working fluids were argon and air at atmospheric pressure and Reynolds numbers up to 300. A 20 m-long DTS was threaded through Ø1 mm capillaries wound around rods as wire-wraps. The sensor generated 173 measurements along each rod at 5 mm resolution for a total of 3300 data locations. A second DTS, 58 m long, was suspended between rods to provide 9300 fluid temperature measurements at 20 mm resolution. Such data density makes it possible to construct 3D maps of the temperature field that are beyond the reach of traditional sensors such as thermocouples. This is illustrated through a series of steady-state and transient tests. As a result, the work demonstrates the feasibility of mapping temperature within the close confines of a rod bundle at resolutions suitable for validation of computational fluid dynamics codes.},
doi = {10.1016/j.nucengdes.2017.05.008},
journal = {Nuclear Engineering and Design},
number = C,
volume = 319,
place = {United States},
year = 2017,
month = 5
}

Journal Article:
Free Publicly Available Full Text
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  • The distributed fiber optic temperature sensing technique represents a new physical approach for temperature measurements in geosciences. This method was applied for long-term surveying of temperature variations with time caused by injecting and extracting hot water in a 600-m-deep well. The measuring system was installed as a permanent sensor in the annulus between casing and tubings. The injection/extraction regime was monitored by repeating the measurements every few weeks. Short-term variations of the temperature during injection and extraction were studied by recording the temperature profile every 1 min over a time period of several hours. Testing shows that the fiber opticmore » temperature sensing technique opens new possibilities for measuring the actual temperature along the entire length of a borehole as well as for monitoring short-term and long-term temperature variations.« less
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