复杂簇状裂纹旋转均匀电流场检测机理及其三维轮廓重构研究

结题报告

项目介绍

AI项目解读

基本信息

批准号：
61903191
项目类别：
青年科学基金项目
资助金额：
25.0万
负责人：
葛玖浩
依托单位：
南京航空航天大学
学科分类：
F0306.自动化检测技术与装置
结题年份：
2022
批准年份：
2019
项目状态：
已结题
起止时间：
2020-01-01 至2022-12-31

项目参与者：
--
关键词：
三维轮廓重构交流电磁场检测技术涡流检测旋转均匀电流场复杂簇状裂纹

项目摘要

Cracks usually occur as a complex colony in pipeline. Cracks in colony may be adjacent or crossed. There are interaction and superposition among crack magnetic signals. The superposition forms a shield to adjacent cracks leading missing detection and quantification error. This influences the accurate evaluation of pipeline residual strength. Up to now, complex crack colony could hardly be sized accurately; moreover, describing method is still simple value. In this project, the detection principle and the 3D profile reconstruction technical system of complex crack colony using rotating uniform eddy current technique are studied to achieve accurate and overall quantification. The distribution and interaction forward model of disturbed electromagnetic field is established. The decomposing algorithm for disturbed magnetic signal of complex crack colony is proposed. Then, the 3D profile reconstruction algorithm of complex crack colony is proposed. The probe and the experimental device of rotating uniform eddy current are developed; furthermore, sensitivity, functionality and algorithm accuracy are tested for later engineering application. Through the study of this project, the bottleneck of complex crack colony accurate quantification is expected to be broken through. The theoretical lack of complex crack colony detection through rotating uniform eddy current technique will be made up. A novel method will be provided to achieve the 3D profile reconstruction of complex crack colony and prevent unexpected accidents pipeline.

管道裂纹常以相邻较近、甚至交叉的复杂簇状裂纹形式出现。复杂簇状裂纹磁场信号存在相互作用和叠加，容易形成保护壁垒，导致漏检或裂纹尺寸量化误差，影响管道剩余强度的准确估计，引发突发性事故。目前，尚未能精确地反演复杂簇状裂纹三维尺寸信息，检测结果仍以简单的数值表征。本课题拟开展复杂簇状裂纹旋转均匀电流场检测机理及其三维轮廓重构技术体系研究，实现复杂簇状裂纹尺寸精确和全面反演。建立复杂簇状裂纹扰动电磁场分布和相互作用“正问题”规律，形成复杂簇状裂纹扰动磁场信号分解“逆过程”方法，提出复杂簇状裂纹三维轮廓重构算法。开发配套检测探头和实验系统，并对系统灵敏度、功能性和算法精度等进行实验验证和测试，为工程应用和成果转化奠定基础。本课题有望突破复杂簇状裂纹精确量化瓶颈，弥补复杂簇状裂纹旋转均匀电流场检测理论的不足，为复杂簇状裂纹的全面三维可视化检测提供一项行之有效的途径，有效预防管道突发事故发生。

结项摘要

结构物中所产生的自然裂纹往往以多条、簇状和交叉等复杂形式存在。采用涡流技术对复杂裂纹进行检测时，复杂裂纹内的各个裂纹的扰动电流产生的磁场将在空间中发生叠加，导致传统方法无法实现复杂裂纹尺寸的准确量化。为实现复杂裂纹的可靠评估，本项目采用旋转均匀电流场检测技术开展复杂裂纹三维轮廓重构研究。项目构建了复杂裂纹检测机理，提出了旋转电磁场信号转化和分解算法。采用有限元方法，提出了旋转均匀电流场简化数值模型，并对模型适用性开展了实验验证。优化旋转电磁场探头结构和激励参数，建立了旋转均匀电流场检测系统和复杂裂纹检测实验台。提出基于电流偶极子的复杂裂纹表面轮廓重构算法和基于有限元迭代法的深度反演算法，最终得到复杂裂纹的三维轮廓，实现复杂裂纹的可视化，最终裂纹反演精度达到82%以上。