Title: Detection, monitoring, and determination of location of changes in metallic structures using multimode acoustic signals

Abstract

Acoustic transducers generate and receive acoustic signals at multiple locations along a surface of rigid structure, wherein longitudinal spacing between transducer locations define measurement zones. Acoustic signals with chosen amplitude-time-frequency characteristics excite multiple vibration modes in the structure within each zone. Small mechanical changes in inspection zones lead to scattering and attenuation of broadband acoustic signals, which are detectable as changes in received signal characteristics as part of a through-transmission technique. Additional use of short, narrowband pulse acoustic signals as part of a pulse-echo technique allows determination of the relative location of the mechanical change within each zone based on the differential delay profiles. For accurate acoustic modeling and simulation, the mesh size, time step, time delay, and time-window size are optimized. Frequency normalization of the Short-Time Fourier Transform of acoustic response output improves experiment-simulation cross-validation. Applications of the method to structures with arbitrarily complex geometries are also demonstrated.

Inventors:

Findikoglu, Alp Tugrul; Ju, Taeho; Chapman, Daniel Robert

Issue Date:

2021-05-04

Research Org.:

Los Alamos National Laboratory (LANL), Los Alamos, NM (United States); Chevron U.S.A. Inc., San Ramon, CA (United States)

Sponsoring Org.:

USDOE

OSTI Identifier:

1823925

Patent Number(s):

10996203

Application Number:

16/800,661

Assignee:

Triad National Security, LLC (Los Alamos, NM); Chevron U.S.A. Inc. (San Ramon, CA)

Patent Classifications (CPCs):

G - PHYSICS G01 - MEASURING G01N - INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES

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G - PHYSICS G01 - MEASURING G01N - INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES

G01N2291/011 - Velocity or travel time
G01N2291/015 - Attenuation, scattering
G01N2291/0234 - Metals, e.g. steel
G01N2291/0289 - Internal structure, e.g. defects, grain size, texture
G01N2291/042 - Wave modes
G01N2291/048 - Transmission, i.e. analysed material between transmitter and receiver
G01N2291/105 - two or more emitters, two or more receivers
G01N2291/269 - Various geometry objects
G01N2291/2695 - Bottles, containers
G01N29/07 - by measuring propagation velocity or propagation time of acoustic waves
G01N29/11 - by measuring attenuation of acoustic waves
G01N29/223 - {Supports, positioning or alignment in fixed situation
G01N29/24 - Probes {
G01N29/326 - {compensating for temperature variations}
G01N29/4409 - {by comparison}
G01N29/4472 - {Mathematical theories or simulation}
G01N29/449 - {Statistical methods not provided for in G01N29/4409, e.g. averaging, smoothing and interpolation}
G01N29/46 - by spectral analysis, e.g. Fourier analysis {or wavelet analysis

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DOE Contract Number:  

89233218CNA000001

Resource Type:

Patent

Resource Relation:

Patent File Date: 02/25/2020

Country of Publication:

United States

Language:

English