Lamb wave generation and reception with time-delay periodic linear arrays: a BEM simulation and experimental study

Area of Science:

• Solid Mechanics
• Acoustics
• Materials Science

Background:

• Lamb waves are crucial for non-destructive testing in plate-like structures.
• Efficient generation and reception of specific Lamb wave modes remain a challenge.

Purpose of the Study:

• To propose and validate a time-delay periodic linear array model for controlled Lamb wave manipulation.
• To analyze the performance and parameter effects on Lamb wave generation and mode selectivity.

Main Methods:

• Development of a time-delay periodic linear array model based on interference principles.
• Simulation of wave generation using a hybrid Boundary Element Method (BEM) technique.
• Experimental validation of two array designs.

Main Results:

• Successful unilateral guided wave emission and reception demonstrated.
• Analysis of array parameter effects on Lamb mode selectivity and generation efficiency.
• 2-D phase velocity-frequency spectrum and wave structure calculations provided insights.

Conclusions:

• The proposed time-delay periodic linear array model effectively controls Lamb wave generation and reception.
• Hybrid BEM simulations and experimental data confirm the model's theoretical designs.
• The study provides a framework for optimizing array parameters for specific Lamb wave applications.