Results 121 to 130 of about 6,744 (161)

Air-coupled Lamb wave tomography

IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 1997
An entirely air-coupled inspection system using a pair of micromachined silicon capacitance transducers has been used to image defects in thin plates of different materials (0.7 mm to 2.22 mm thick) using air-coupled Lamb wave tomography. A filtered back projection algorithm was used in a form of difference tomography to reconstruct images of defects ...
W, Wright, D, Hutchins, D, Jansen, D, Schindel   +3 more
openaire   +2 more sources

Lamb wave interaction with light

Journal of Applied Physics, 1985
The interaction of light with Lamb waves propagating in transparent plates has been investigated. The analytical study has been done by considering a three-step interaction, at the limiting surfaces and within the propagation medium. Experimental data are given, relative to isotropic crystal plates in the MHz frequency regions and compared with theory.
A. Alippi, P. Diodati, D. Maccari, G. Socino   +3 more
openaire   +1 more source

On conversion of Lamb waves to leaky Lamb waves in a plate partially immersed into the liquid

The Journal of the Acoustical Society of America, 1986
The problem of Lamb waves diffraction on the boundary of separation of the free and immersed (into the liquid) parts of the elastic plate is theoretically analyzed. In the theoretical model, it is assumed that the free part of the plate is separated from the liquid by infinitely thin air barriers.
openaire   +1 more source

Rayleigh and Lamb Waves on Cylinders

The Journal of the Acoustical Society of America, 1969
Acoustic waves propagating on the surface of solid and hollow elastic cylinders immersed in water were observed and their characteristics shown to be consistent with theory. These waves were excited by an 11-μsec pulse, projected onto the cylindrical surface at an excitation angle given by sin 1(co/cs), where co is the velocity of sound in water and cs
R. E. Bunney, R. R. Goodman, S. W. Marshall   +2 more
openaire   +1 more source

Subsonic lamb waves in anisotropic layers

Journal of Applied Mathematics and Mechanics, 2001
According to \textit{H. Lamb} [Proc. Roy. Soc. London. Ser. A. 93, No. 648, 114-128 (1917)] a harmonic wave consists of several partial waves of the form \[ u_k = m_ke^{ir\gamma_k x\cdot v}e^{ir(n\cdot x -ct}.\tag{1} \] The author shows that in the case of the Lamb wave propagating with subsonic velocity in anisotropic layers the representation (1 ...
openaire   +2 more sources

Lamb waves and lamination detection

Ultrasonics, 1967
Abstract Lamb waves at the fundamental, and of higher orders, can be excited with sufficient intensity for lamination detection in thick plates if large-area probes and long acoustic pulses are used. Hot-rolled steel plates up to 16mm in thickness can be tested, and clear and unambiguous results obtained.
E. Lehfeldt, P. Höller
openaire   +1 more source

Processing of Lamb Wave Signals

2009
Substantially dependent on signals captured by a sensor or sensor network, the accuracy and precision of a Lamb-wave-based damage identification approach is largely subject to the processing and interpretation of signals. Captured Lamb wave signals carry comprehensive information as to interference existing in the path of wave propagation, such as ...
Zhongqing Su, Lin Ye
openaire   +1 more source

Activating and Receiving Lamb Waves

2009
Over the past few decades there have been substantial advances in the design and development of functional materials. Many of the products, piezoelectric materials for example, have been widely used to build a variety of transducers for activating and receiving Lamb waves.
Zhongqing Su, Lin Ye
openaire   +1 more source

Thermoelastic Coupling to Lamb Waves

IEEE 1986 Ultrasonics Symposium, 1986
We consider the thermoelastic generation of Lamb waves produced by incidence of a light beam on a solid plate. In addition to the variables relevant for thermoelastic SAW generation -- frequency and the optical, thermal, and acoustical properties of the materials used -- one has the plate thickness and mode type (symmetric, anti-symmetric).
openaire   +1 more source

Lamb wave-based acoustofluidics

The Journal of the Acoustical Society of America
Both bulk acoustic wave (BAW) and surface acoustic wave (SAW) acoustofluidic technologies have been widely utilized for particle manipulation. However, within fluid, these waves tend to propagate as bulk waves or leaky bulk waves, resulting in undesirable acoustic streaming that causes unstable particle manipulation.
Feiyan Cai, Jiaqi Liu, Hairong Zheng
openaire   +1 more source