公开(公告)号：US20240133845A1

公开(公告)日：2024-04-25

申请号：US17971429

申请日：2022-10-20

Applicant: XI'AN JIAOTONG UNIVERSITY

Inventor： Zhibo YANG ,  Jiahui CAO ,  Haoqi LI ,  Shaohua TIAN ,  Laihao YANG ,  Zengkun WANG ,  Xuefeng CHEN ,  Shuming WU

IPC: G01N29/12 ,  G06F17/14 ,  G06F17/16

CPC classification number: G01N29/12 ,  G06F17/14 ,  G06F17/16

Abstract: The present disclosure discloses a method for detecting a natural frequency of a blade by a single blade tip timing sensor. In the method, two segments of displacement data vectors are subjected to dot product to obtain a product data vector after multiplication of corresponding serial numbers, the product data vector is subjected to low-frequency filtering, the filtered product vector is subjected to Hilbert transform to obtain an instantaneous phase, the instantaneous phase is subjected to discrete Fourier transform, an absolute value of a natural frequency difference between blades is extracted from amplitude frequency data, blades on a bladed disk are subjected to permutation and combination to obtain absolute values of the natural frequency differences between all the blades, a sum of the absolute values of the natural frequency differences between each blade and other blades is calculated.

公开(公告)号：US20240219900A1

公开(公告)日：2024-07-04

申请号：US18543433

申请日：2023-12-18

Applicant: XI'AN JIAOTONG UNIVERSITY

Inventor： Shibin WANG ,  Yiming ZHENG ,  Chuanyi CHENG ,  Baoqing DING ,  Zhibin ZHAO ,  Xuefeng CHEN

IPC: G05B23/02 ,  G01M13/045

CPC classification number: G05B23/0281 ,  G01M13/045 ,  G05B23/024

Abstract: The present disclosure discloses a nonlinear sparsity-based instantaneous dynamic frequency fault diagnosis method for an aviation intermediate bearing. In the method, a vibration signal and a rotating speed signal of high and low voltages of the intermediate bearing are acquired, and a vibration signal fragment x under a specific working condition is intercepted according to the rotating speed signal; a nonlinear sparse time-frequency enhancement model or a nonlinear sparse enhancement algorithm model is established based on derivative window function short-time Fourier transform of the vibration signal; the nonlinear sparse time-frequency enhancement model is solved or the nonlinear sparse enhancement algorithm model is improved by using a fast iterative shrinkage threshold algorithm and combining a k sparse strategy, and finally a nonlinear sparse time-frequency representation result {circumflex over (N)}x, may be obtained through iterative optimization.

公开(公告)号：US20240230597A9

公开(公告)日：2024-07-11

申请号：US17971429

申请日：2022-10-21

Applicant: XI'AN JIAOTONG UNIVERSITY

Inventor： Zhibo YANG ,  Jiahui CAO ,  Haoqi LI ,  Shaohua TIAN ,  Laihao YANG ,  Zengkun WANG ,  Xuefeng CHEN ,  Shuming WU

IPC: G01N29/12 ,  G06F17/14 ,  G06F17/16

CPC classification number: G01N29/12 ,  G06F17/14 ,  G06F17/16

Abstract: The present disclosure discloses a method for detecting a natural frequency of a blade by a single blade tip timing sensor. In the method, two segments of displacement data vectors are subjected to dot product to obtain a product data vector after multiplication of corresponding serial numbers, the product data vector is subjected to low-frequency filtering, the filtered product vector is subjected to Hilbert transform to obtain an instantaneous phase, the instantaneous phase is subjected to discrete Fourier transform, an absolute value of a natural frequency difference between blades is extracted from amplitude frequency data, blades on a bladed disk are subjected to permutation and combination to obtain absolute values of the natural frequency differences between all the blades, a sum of the absolute values of the natural frequency differences between each blade and other blades is calculated.

公开(公告)号：US20220205952A1

公开(公告)日：2022-06-30

申请号：US17514868

申请日：2021-10-29

Applicant: XI'AN JIAOTONG UNIVERSITY

Inventor： Zhibo YANG ,  Mingfeng ZHU ,  Xuefeng CHEN ,  Shaohua TIAN ,  Ming LI ,  Xingwu ZHANG

IPC: G01N29/06 ,  G06T7/00 ,  G01N29/04 ,  G01N29/24 ,  G01N29/46

Abstract: The disclosure discloses a Lamb wave phased array focus-imaging method based on a frequency response function. In the method, a piezoelectric sensor array is arranged on a surface of a tested structure, the frequency response function of an excitation and acquisition pair formed by an excitation array element and an acquisition array element is calculated according to a full-band response signal, and a dispersion pre-compensation signal is constructed; the dispersion pre-compensation signal and the frequency response function are multiplied in a frequency domain to obtain a frequency domain pre-compensation response signal; and according to a distance from the acquisition array element to a focal point at the coordinates, the dispersion of the frequency domain pre-compensation response signal is post-compensated, so as to obtain a frequency domain dispersion post-compensation signal until all sensor excitation and acquisition pairs are traversed.

公开(公告)号：US20210389207A1

公开(公告)日：2021-12-16

申请号：US17325209

申请日：2021-05-20

Applicant: XI'AN JIAOTONG UNIVERSITY

Inventor： Baijie QIAO ,  Chunyan AO ,  Xuefeng CHEN ,  Hongrui CAO ,  Yu SUN

IPC: G01M7/02 ,  G01B21/32 ,  G01M15/14 ,  G06F30/23

Abstract: The present invention discloses a non-contact dynamic strain field measuring method and system for a rotating blade. The method includes the following steps: establishing a three-dimensional finite element model of a to-be-measured rotating blade, and extracting modal parameters of the three-dimensional finite element model; determining the number and axial mounting positions of blade tip timing sensors; constructing a conversion matrix of finite measuring point displacement and an overall strain field; and acquiring blade tip finite position displacement of the rotating blade based on the blade tip timing sensors, and acquiring, by a dynamic strain, dynamic strains of the rotating blade at any moment, on any position and in any direction based on modal processing of the conversion matrix.