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The Study of Localized Crack-Induced Effects of Nonlinear Vibro-Acoustic Modulation
Dariusz Broda1, Krzysztof Mendrok1, Vadim V Silberschmidt2
1Department of Robotics and Mechatronics, AGH University of Science and Technology, Al. A. Mickiewicza 30, 30-059 Kraków, Poland.
Materials (Basel, Switzerland)
|February 25, 2023
Summary
This study investigates nonlinear interactions in cracked beams, revealing localized vibro-acoustic modulation near cracks. This effect aids in pinpointing cracks and distinguishing their nonlinear signatures from other sources.
Area of Science:
- Solid Mechanics
- Nonlinear Dynamics
- Acoustics
Background:
- Cracks in structural beams can alter their dynamic behavior.
- Nonlinear phenomena in vibrating systems are crucial for accurate modeling.
- Vibro-acoustic modulation is a key indicator of structural damage.
Purpose of the Study:
- To investigate the nonlinear interaction between longitudinal vibration and ultrasound in cracked beams.
- To analyze the localization effect of nonlinear vibro-acoustic modulation near cracks.
- To differentiate crack-induced nonlinearities from other sources.
Main Methods:
- Numerical simulations using the finite element (FE) method.
- Investigation of various crack models: bi-linear, open, and breathing cracks.
- Parametric study considering crack depth, location, and boundary conditions in a 2D beam model.
Main Results:
- Nonlinear crack-wave modulations are significantly enhanced near the crack.
- The localized nonlinear effect allows for precise crack localization.
- Successful separation of crack-induced nonlinearity from other nonlinear sources was achieved.
Conclusions:
- Nonlinear interactions provide a sensitive method for detecting and localizing cracks in beams.
- The localized vibro-acoustic modulation is a strong indicator of crack presence and severity.
- This research offers a pathway for advanced structural health monitoring techniques.
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