Calculation of leaky Lamb waves with a semi-analytical finite element method

Area of Science:

• Acoustics
• Materials Science
• Computational Mechanics

Background:

• Semi-analytical finite element method (SAFE) is standard for guided wave analysis in structures.
• Existing SAFE techniques are limited for plates with leaky media, hindering applications like water-loaded plates and pipes.
• Accurate modeling of leaky Lamb waves is essential for non-destructive testing and structural health monitoring.

Purpose of the Study:

• To extend the SAFE method for calculating leaky Lamb waves in plates immersed in leaky media.
• To develop a novel SAFE formulation leveraging the harmonic plane wave generation in leaky media.
• To validate the accuracy of the proposed SAFE method against established theoretical studies.

Main Methods:

• Formulation of a new SAFE solution exploiting the characteristic harmonic plane wave generation in leaky media.
• Application of the developed SAFE technique to analyze single-side and double-side water-loaded plates.
• Comparison of dispersion curves calculated by the new SAFE method with existing theoretical results.

Main Results:

• The SAFE calculations for dispersion curves showed excellent agreement with previous theoretical studies, confirming high accuracy.
• The study successfully calculated dispersion curves and attenuation curves for total transmission modes and leaky plate modes.
• Displacement distributions for various leaky Lamb wave modes were analyzed in single-side and double-side water-loaded plates.

Conclusions:

• The developed SAFE method provides an accurate and efficient tool for analyzing leaky Lamb waves in fluid-loaded plates.
• This advancement extends the applicability of SAFE techniques to a broader range of guided wave inspection scenarios.
• The findings contribute to improved understanding and modeling of wave propagation in complex, fluid-structure interaction environments.