磁致伸缩纵向导波管道检测数值建模与分析

检测模型是磁致伸缩纵向导波检测技术发展的基石。现有磁致伸缩纵向导波检测模型存在不包含接收过程和不包含静态磁场计算等不足,难以满足设计优化接收传感器、增强导波检测信号等方面的研究需求。因此,以磁致伸缩纵向导波管道检测为背景,分析激励和接收过程中的控制方程,在此基础上建立了包括激励过程、声场传播和接收过程的有限元模型。分别采用仿真和实验分析了接收线圈的提离效应,仿真和实验结果吻合较好,验证了该数值模型的正确性。

Numerical modeling and analysis of the longitudinal guided wave pipeinspection based on magnetostrictive effect

Many models have been developed for investigating the longitudinal guided wave pipe inspection technology based on magnetostrictive effect. Most of these models focus on the generation process and ignore the receiving process of the longitudinal guided waves. Moreover, the static magnetic field produced by the transducer is simplified into a uniform static magnetic field. Therefore, the existing models could not meet the requirement of optimizing the receiver coil structure and enhancing the signal strength. In this paper, a new finite element model is built to simulate the process of the longitudinal guided wave steel pipe inspection based on magnetostrictive effect, which includes the generation, propagation and reception of longitudinal guided waves. The lift off effect of the receiver coil is investigated with both simulation and experiment, and the simulation and experiment results fit well with each other, which verifies the effectiveness and accuracy of the finite element model.