Intelligent lamb wave defect positioning method applied to large plate-shell structure

Abstract

The invention discloses an intelligent lamb wave defect positioning method applied to a large plate-shell structure, and the method comprises the steps: according to a population individual detectionpath correlation analysis data structure, calculating a signal wave packet propagation distance based on a time flight principle, calculating the number of detection paths in a Lamb wave detection array, calculating the sum of the distances from each individual in the evolutionary population to the excitation bits and the receiving bits in all the detection paths, and constructing reserved individuals for defect detection and analysis individuals for algorithm iterative update operation; constructing a diversity maintenance population in a mode of combining the analysis individuals of which the spatial Euclidean distances are greater than a preset threshold in adjacent iterative analysis with the contemporary analysis individuals, and carrying out diversity maintenance; and adopting free individual release mode for population updating, and controlling and analyzing the individual release number through a clustering algorithm and the population individual association detection path number; and setting a cut-off condition according to the iteration times and the average value change of the fitness of the population individuals reserved in the adjacent algebra, so that the positioningdetection of the large-scale plate-shell structure defects can be quickly realized.

Description

technical field [0001] The invention belongs to the field of ultrasonic non-destructive testing, and in particular relates to an intelligent Lamb wave defect positioning method applied to large plate and shell structures. Background technique [0002] Large-scale plate and shell structures are important structural components of equipment such as aircraft, ships, and energy storage tanks. However, different types of defects may occur during processing and service, endangering the safety of equipment. For example: defects such as shrinkage cavities, delamination, debonding in composite material plates, fatigue cracks in metal plates. Lamb waves are elastic guided waves propagating in the plate and shell structure. They have the characteristics of multiple modes, slow attenuation, and sensitivity to structural defects and material property changes. They can be used for long-distance and rapid detection of defects in plates. Detection and monitoring. With the rise of artificia...

AI Technical Summary

Problems solved by technology

[0003] At present, combining the intelligent algorithm and the Lamb wave defect location algorithm, there are still many problems in realizing the intelligentization of the large-scale plate and shell structure defect location method, mainly including 1. The intelligent Algorithms analyze the relationship between the data structure and the Lamb wave detection array and defect detection signal features, making it difficult to build an intelligent defect location analysis function model

2. The population screening mechanism, diversity maintenance mechanism and update mechanism in the intelligent algorithm have not been clarified to ensure that the intelligent defect location method has the statistical and fuzzy characteristics of the classic Lamb wave defect location algorithm (ellipse imaging algorithm)

Images