Related Experiment Video
Updated: May 21, 2026
09:36
Characterization of Anisotropic Leaky Mode Modulators for Holovideo
Published on: March 19, 2016
Interaction of Lamb modes with an inclusion
1Laboratorium voor Akoestiek en Thermische Fysica, Departement Natuurkunde, K.U. Leuven, Celestijnenlaan 200 D, B-3001 Leuven, Belgium.
Ultrasonics
|June 26, 2012
Summary
Lamb modes interacting with steel plate inclusions show efficient mode conversion, particularly S0 to A0 modes. Conversion efficiency depends on inclusion size, location, and material properties, influenced by stress profiles.
Area of Science:
- Solid Mechanics
- Wave Propagation
- Materials Science
Background:
- Lamb modes are crucial for understanding wave propagation in thin plates.
- Thin inclusions can alter wave behavior, impacting structural integrity.
- Predicting mode conversion is vital for non-destructive testing.
Purpose of the Study:
- To analyze Lamb mode interaction with thin inclusions in steel plates.
- To investigate the influence of inclusion properties and location on mode conversion.
- To quantify conversion coefficients for different incident modes.
Main Methods:
- Modal decomposition method applied to analyze wave propagation.
- Calculation of mode conversion coefficients.
- Parametric study varying inclusion geometry, location, and material properties.
Main Results:
- Conversion efficiency increases with inclusion cross-section and acoustic impedance mismatch.
- Symmetric conversion of incident S0 mode to reflected/transmitted A0 modes observed, sensitive to inclusion proximity to the plate center.
- Incident A0 mode conversion to reflected A0 mode shows strong depth dependency, potentially vanishing at specific depths.
Conclusions:
- Inclusion location and geometry significantly influence Lamb mode conversion.
- Stress profile correlations suggest mechanisms for observed conversion dependencies.
- Material property mismatch is a key driver of conversion efficiency.
Related Concept Videos
01:24Mutual Inductance
Inductance is the property of a device that tells us how effectively it induces an emf in another device. In other words, it is a physical quantity that expresses the effectiveness of a given device.
When two circuits carrying time-varying currents are close to one another, the magnetic flux through each circuit varies because of the changing current in the other circuit. Consequently, an emf is induced in each circuit by the changing current in the other. Therefore, this type of emf is called...
When two circuits carrying time-varying currents are close to one another, the magnetic flux through each circuit varies because of the changing current in the other circuit. Consequently, an emf is induced in each circuit by the changing current in the other. Therefore, this type of emf is called...
00:58¹H NMR Signal Integration: Overview
The intensity of a signal, which can be represented by the area under the peak, depends on the number of protons contributing to that signal. The area under each peak is shown as a vertical line called an integral, with the integral value listed under it, as seen in the proton NMR spectrum of benzyl acetate. Each integral value is divided by the smallest integral value to obtain the ratio of the number of protons producing each signal. The ratio reveals the relative number of protons and not...
01:21Impedance Combination
Consider a string of christmas lights, each bulb symbolizing an impedance element. In this series configuration, the flow of electric current remains uniform across every component. This behavior aligns with Kirchhoff's Voltage Law (KVL), which asserts that the total impedance in such a setup equals the sum of individual impedances—akin to resistors in series. It follows that the voltage from the power source is distributed proportionally among these components, adhering to the voltage division...
01:30Oscillations In An LC Circuit
An idealized LC circuit of zero resistance can oscillate without any source of emf by shifting the energy stored in the circuit between the electric and magnetic fields. In such an LC circuit, if the capacitor contains a charge q before the switch is closed, then all the energy of the circuit is initially stored in the electric field of the capacitor. This energy is given by
01:20Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)
Two NMR-active nuclei bonded to a central atom can be involved in geminal or two-bond coupling. Geminal coupling is commonly seen between diastereotopic protons in chiral molecules and unsymmetrical alkenes, among others.
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
01:27¹H NMR: Long-Range Coupling
The coupling interactions of nuclei across four or more bonds are usually weak, with J values less than 1 Hz. While these are usually not observed in spectra, the presence of multiple bonds along the coupling pathway can result in observable long-range coupling.
In alkenes, spin information is communicated via σ–π overlap, as seen in allylic (four-bond) and homoallylic (five-bond) couplings. These coupling interactions are stronger when the σ bond is parallel to the alkene π orbitals.
In alkenes, spin information is communicated via σ–π overlap, as seen in allylic (four-bond) and homoallylic (five-bond) couplings. These coupling interactions are stronger when the σ bond is parallel to the alkene π orbitals.