Finite Element Modeling Approaches, Experimentally Assessed, for the Simulation of Guided Wave Propagation in Composites

Abstract

Today, structural health monitoring (SHM) systems based on guided wave (GW) propagation represent an effective methodology for understating the structural integrity of primary and secondary structures, also made of composite materials. However, the sensitivity to damage detection promoted by these systems can be altered by such factors as the geometry of the monitored parts, as well as the environmental and operational conditions (EOCs). Experimental investigations are fundamental but require a long time period and are costly, especially for tests in real-life scenarios. Experimentally validated simulations can help designers to improve SHM effectiveness due to the possibility of further broadening study on the different geometries, load cases, and material types with less effort. From this point of view, this paper presents two finite element (FE) modeling approaches for the simulation of GW propagation in composite panels. The case study consists of a flat and a curved composite panel. The two approaches herein investigated are based on implicit and explicit finite element analysis (FEA) formulations. The comparison of the predicted measures against the experimental dataset allowed the assessment of the levels of accuracy provided by both modeling approaches with respect to the dispersion curves. Furthermore, to assess the different curvature sensitivities of the proposed numerical and experimental approaches, the extracted dispersion curves for both flat and curved panels were compared.

Numerical Study of Ultrasonic Guided Wave in Composite Reinforced Panels with Different Stiffener Shapes

“…It must be underlined that the group velocity has been calculated by means of the energetic center of the signal envelope, as in literature. [ 21 ]…”

“…The most efficient way to study the phenomenon is to model it using numerical schemes to solve the characteristic equations. [21] This approach is particularly useful when studying complex phenomena like reflected, transmitted, and converted wave behavior in stiffened plates. [14,22] In this work, two numerical models were developed to investigate the behavior of ultrasonic guided waves in stiffened fiberreinforced polymeric (FRP) plates, specifically with two different stiffening shapes: Form C and Form Omega.…”

Numerical Analysis on the Propagation of Ultrasonic Guided Wave in Damaged Carbon Fiber Reinforced Polymer Laminate

“…The studied panel consists of a CFRP laminated made of eight unidirectional laminae with the stacking sequence of [0] 8 . Its a [25] For UGW actuation, the bottom left sensor (PZT 2) has been excited with a Hanning windowed tone burst signal with five cycles, with a central frequency of 200 kHz, and a peak-to-peak amplitude equals to 2 V (Figure 2A). The panel and the sensors were modeled by FEM using Abaqus CAE environment (Dassault Systems Simulia Corp, Providence, RI, USA) using the ex-plicit formulation scheme, that can provide accurate results with low computational costs.…”

Guided wave energy focusing and steering in composite laminates

“…Whilst the A0 mode has lower directional variation, this is still significant enough to impact damage detection [9]. The directional dependency of group velocity has been well established [5,[10][11][12][13][14] , however equivalent studies for the phase velocity are limited [15].…”