Signal Processing for Determining Water Height in Steam Pipes with Dynamic Surface Conditions

Lih, Shyh-Shiuh; Lee, Hyeong Jae; Bar-Cohen, Yoseph

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NASA NTRS · 20170007009

Signal Processing for Determining Water Height in Steam Pipes with Dynamic Surface Conditions

Lih, Shyh-Shiuh·Lee, Hyeong Jae·Bar-Cohen, Yoseph

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Abstract

An enhanced signal processing method based on the filtered Hilbert envelope of the auto-correlation function of the wave signal has been developed to monitor the height of condensed water through the steel wall of steam pipes with dynamic surface conditions. The developed signal processing algorithm can also be used to estimate the thickness of the pipe to determine the cut-off frequency for the low pass filter frequency of the Hilbert Envelope. Testing and analysis results by using the developed technique for dynamic surface conditions are presented. A multiple array of transducers setup and methodology are proposed for both the pulse-echo and pitch-catch signals to monitor the fluctuation of the water height due to disturbance, water flow, and other anomaly conditions.

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BibTeX RIS

Lih, Shyh-Shiuh, Lee, Hyeong Jae, Bar-Cohen, Yoseph. 2015-03-08. Signal Processing for Determining Water Height in Steam Pipes with Dynamic Surface Conditions. https://ntrs.nasa.gov/citations/20170007009

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