基于半解析有限元法的多层复合环面周向导波计算

Computation of Circumferential Guided Ultrasonic Waves in Multilayered Composite Annuli Using Semi-Analytical Finite Element Method

摘要:

周向超声导波在多层复合圆管的快速缺陷检测与定量材料表征方面具有优秀的应用潜力，结合传感器网络技术，可构建智能材料与结构。精确计算周向导波的频散特性是实现上述目标的关键。传统的频散曲线求解方法大多只适用于各向同性介质且单层环面的情形，而对于工程结构中多层复合圆管则难以甚至无法求解。从弹性波动理论出发，结合COMSOL Multiphysics商用分析平台，发展了半解析有限元（SAFE）方法的计算框架，实现了对周向导波频散关系的精确求解，并在两种典型工业复合圆管结构中得到应用验证。研究表明，所提出的方法可以计算任意材料属性、任意层数以及任意环向截面形状的复合圆管中周向导波的频散曲线，具有重要的工程应用价值。

Abstract:

Circumferential ultrasonic guided waves feature the excellent potential of rapid screening and characterizing multilayered composite cylindrical structures， whilst the key to achieving these is to extract their dispersion relations. The traditional approaches for solving dispersion equations are only applicable for isotropic single-layer annulus， which however， are difficult or even impossible to solve guided waves in anisotropic multilayered annuli. This paper develops a semi-analytical finite element （SAFE） approach to compute circumferential guided waves based on elastodynamics， via COMSOL Multiphysics coefficient PDE（partial differential equation） platform. The method and associated results are cross validated by the dispersion curves reported in the literature， and are then applied to two typical engineering cylindrical structures. The proposed approach has manifested itself by extendable applications in industry， as it potentially allows for the computation of circumferential guided waves in multilayered composite annuli with arbitrary material properties， arbitrary number of layers， and arbitrary circumferential cross-sectional shapes.