A Location Method Using Sensor Arrays for Continuous Gas Leakage in Integrally Stiffened Plates Based on the Acoustic Characteristics of the Stiffener.

Shijiu Jin,Jiaqiang Wang,Yibo Li,Xu Bian,Lei Qi,Hao Feng

doi:10.3390/s150924644

Shijiu Jin, Jiaqiang Wang + Show 4 more

Open Access

https://doi.org/10.3390/s150924644

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Abstract

This paper proposes a continuous leakage location method based on the ultrasonic array sensor, which is specific to continuous gas leakage in a pressure container with an integral stiffener. This method collects the ultrasonic signals generated from the leakage hole through the piezoelectric ultrasonic sensor array, and analyzes the space-time correlation of every collected signal in the array. Meanwhile, it combines with the method of frequency compensation and superposition in time domain (SITD), based on the acoustic characteristics of the stiffener, to obtain a high-accuracy location result on the stiffener wall. According to the experimental results, the method successfully solves the orientation problem concerning continuous ultrasonic signals generated from leakage sources, and acquires high accuracy location information on the leakage source using a combination of multiple sets of orienting results. The mean value of location absolute error is 13.51 mm on the one-square-meter plate with an integral stiffener (4 mm width; 20 mm height; 197 mm spacing), and the maximum location absolute error is generally within a ±25 mm interval.

Highlights

For some special application requirements, such as spacecraft, stiffeners are used to add structural rigidity with minimal additional weight
A series of experiments have been performed with the sensor array at a variety of locations on the test plate to verify the accuracy of the proposed method
In order to solve the location problem of continuous gas leakage in pressurized vessels with an integral stiffener, this paper proposes a location method which can obtain a high-accuracy location result on integrally stiffened plate

Summary

Introduction

For some special application requirements, such as spacecraft, stiffeners are used to add structural rigidity with minimal additional weight. The requirements of safety protection for this kind of vessel are higher. Once any position on the wall of the vessel is hit or corroded so that a hole is formed, leakage occurs, and it can affect the tightness of vacuum structures, reduce the system operational safety coefficient, and cause economic losses. An effective detection method which can quickly identify the leakage source is very necessary. The AE location method involves analyzing the signal collected by the AE sensors at different positions to obtain the time difference information and get the leakage source location through calculation (the typical one is the time difference of arrival (TDOA)

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Results

Conclusion