(192c) Ultrasonic Measurements of Temperature Distribution and Heat Flux Vectors in Solid Components of Energy Conversion Processes

normal">Ultrasonic Measurements of Temperature Distribution and Heat Flux Vectors in
Solid Components of Energy Conversion Processes

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normal">Yunlu Jia and Mikhail Skliar, University of Utah, Salt Lake City, UT

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normal">Background, Motivation, and Objective: " times new roman en-us>Extreme environmental conditions of high temperatures,
pressures, chemical aggressiveness, and mechanical abrasion are common in
military, airspace, energy conversion, and nuclear applications. In such
environments, the most hardened insertion sensors do not perform reliably for
long. For such environments, we have developed an ultrasonic method for
measuring the spatial distribution of temperatures in solid materials and,
specifically, across containments of extreme processes. normal">

Statement of Contribution/Method: We describe a novel ultrasonic approach to the measurements of the
temperature distribution and heat fluxes in solids [1-3]. We use the ultrasound
propagation paths or waveguides structured to contain engineered or naturally
occurring echogenic features which produce a train of echoes in response to an
excitation pulse, Fig. 1. The time of flight between echoes encodes the
information on the temperature distribution in the corresponding segment, which
we reconstruct using its parametrization by the heat conduction model or as a piecewise
linear function.

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margin-left:0in;margin-bottom:.0001pt;line-height:normal"> normal">Results: This paper describes the laboratory
and pilot-scale testing of the developed approach. The validation results show
that the estimated temperature profile is correctly captured, and the
measurement accuracy can be comparable with traditional insertion sensors. It
is further shown that by supplementing the ultrasound data with the surface temperature
measurements, the entire volumetric distribution of the internal temperature
inside of solid samples can be estimated noninvasively and used to reconstruct the
corresponding internal heat fluxes. We will discuss the advantages this
approach, which include its suitability for in-situ and non-destructive
measurements in extreme environments, a broad range of temperatures, locations
inaccessible to the traditional insertion sensors, and the applicability to the
measurements of heat fluxes in solids.

margin-left:0in;margin-bottom:.0001pt;line-height:normal"> normal">[1] Y. Jia & M. Skliar, Energy & Fuels, 2016. [2] Y. Jia et
al., Ultrasonics, 2016. [3] M.
Skliar, et al., US Patents 8,801,277 B2 and
9,212,956.