US 11,768,180 B1Granted

Method for ultrasonic guided wave quantitative imaging in form of variable array

AssigneeNanjing University of Aeronautics and Astronautics

InventorsZhenghua Qian, Zhi Qian, Peng Li, Xianwei Wu, Chen Yang, Yinghong Zhang

Life of this patent

Estimating the term…

Loading patent…

Abstract

The present disclosure relates to a method for ultrasonic guided wave quantitative imaging in a form of variable array and belongs to the technical field of ultrasonic non-destructive testing. The method includes: converting a non-linear lippmann-Schwinger equation into a form of linear summation by a method of moments; and selecting acquisition arrays with different numbers of probes to measure a scattered field signal, and modifying Green's functions by variable born approximation for continuous iterations to approximate a true solution, so as to obtain a final objective function Ok to be solved. According to the present disclosure, by adjusting the arrays, the number of probes and appropriate solution algorithm can be selected based on the testing accuracy; and the method can achieve quantitative evaluation of non-destructive testing, and can be widely used in practical guided wave testing applications of industrial non-destructive testing.

Claims7

Dependent claims

A method for ultrasonic guided wave quantitative imaging in a form of variable array, comprising:

converting a non-linear integral result of a lippmann-Schwinger equation into a form of linear summation
U
(
t
)
=
U
(
in
)
+
C
⁢
O
⁢
U
(
t
)
U
(
s
)
=
D
⁢
O
⁢
U
(
t
)
by a method of moments, U(t) denoting a total field, U(in) denoting an incident field, U(s) denoting a scattered field, C denoting a Green's function of a zero-defect aluminum plate, O denoting an objective function to be solved, D denoting a Green's function of a defective aluminum plate;
selecting, based on data of a measured scattered field, acquisition arrays with different numbers of probes as an initial input, selecting different solution algorithms for the acquisition arrays with different numbers of probes, and modifying the Green's functions by variable born approximation for continuous iterations to approximate a true solution, so as to obtain a final objective function Ok to be solved;
and
converting, through a dispersion curve, the final objective function Ok to be solved into a form of thickness d, wherein d=f(Ok), and performing imaging in terms of a thickness of each point on a plate, pixels of each point representing the thickness of the point on the plate.

33 more elements

Dependencies are inferred from the claim text.

Facts

Application: 18/176,439Filed 28 Feb 2023
Priority: CN 202210701315.316 Jun 2022
Granted: 26 Sep 2023
Term ends: Not estimatedThe source records don’t support an estimate.

Classification15 codes

G01N 29/069
Imaging: defect imaging, localisation and sizing using, e.g. time of flight diffraction [TOFD], synthetic aperture focusing technique [SAFT],…
G01N 29/041
Analysing solids: on the surface of the material, e.g. using Lamb, Rayleigh or shear waves
G01N 29/0654
Visualisation of the interior, e.g. acoustic microscopy: imaging
G01N 29/4481
Processing the detected response signal , e.g. electronic circuits specially adapted therefor: neural networks