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Gerald A Domoto - One of the best experts on this subject based on the ideXlab platform.

  • Laser-induced Acoustic Wave generation/propagation/interaction in water in various internal channels
    Applied Physics A, 2010
    Co-Authors: Seung Hwan Ko, Costas P Grigoropoulos, Nick Kladias, Elias Panides, Gerald A Domoto
    Abstract:

    Short pulsed laser-induced single Acoustic Wave generation, propagation, interaction within a water-filled internal channel are experimentally and numerically studied. A large-area, short-duration, single-Plane Acoustic Wave was generated by the thermoelastic interaction of a homogenized nanosecond pulsed laser beam with a liquid–solid interface and propagated at the speed of sound in water. Laser flash Schlieren photography was used to visualize the transient interaction of the Plane Acoustic Wave in various internal channel structures ((a) sudden expansion and contraction channels, (b) bifurcating channels, (c) gradual contraction wall channels and (d) a cylinder). Fairly good agreement between the experimental results and numerical simulation is observed.

  • laser induced Plane Acoustic Wave generation propagation and interaction with rigid structures in water
    Journal of Applied Physics, 2008
    Co-Authors: Seung Hwan Ko, Nipun Misra, Costas P Grigoropoulos, Nick Kladias, Elias Panides, Gerald A Domoto
    Abstract:

    Short pulsed laser induced single Acoustic Wave generation, propagation, interaction with rigid structures, and focusing in water are experimentally and numerically studied. A large area short duration single Plane Acoustic Wave was generated by the thermoelastic interaction of a homogenized nanosecond pulsed laser beam with a liquid-solid interface and propagated at the speed of sound in water. Laser flash schlieren photography was used to visualize the transient interaction of the Plane Acoustic Wave with various submerged rigid structures [(a) a single block, (b) double blocks, (c) 33° tilted single block, and (d) concave cylindrical Acoustic lens configurations]. Excellent agreement between the experimental results and numerical simulation is observed. Our simulation results demonstrate that the laser induced planar Acoustic Wave can be focused down to several tens of micron size and several bars in pressure.

  • laser induced short Plane Acoustic Wave focusing in water
    Applied Physics Letters, 2007
    Co-Authors: Seung Hwan Ko, Nipun Misra, Costas P Grigoropoulos, Nick Kladias, Elias Panides, Gerald A Domoto
    Abstract:

    Laser induced high frequency Acoustic Wave generation, propagation, and focusing in water are studied. A large area, flat, and short duration Acoustic Wave was generated by the thermoelastic interaction of a homogenized short pulsed laser beam with the liquid-solid interface and propagated at the speed of sound. Laser flash Schlieren photography was used to visualize the transient interaction of the flat Acoustic Wave with a cylindrical concave lens and the subsequent Acoustic Wave focusing. Numerical simulations showed the Acoustic Wave could be focused to several tens of microns in size and 7bars in pressure.

Farhang Honarvar - One of the best experts on this subject based on the ideXlab platform.

  • multiple scattering of an obliquely incident Plane Acoustic Wave from a grating of immersed cylindrical shells
    Applied Acoustics, 2011
    Co-Authors: Sina Sodagar, Farhang Honarvar, A.n. Sinclair
    Abstract:

    The study of the interaction of Acoustic Waves with cylindrical structures has numerous applications including the ultrasonic nondestructive testing of materials. In this paper, using a new mathematical model presented for the scattering of obliquely incident Plane Acoustic Waves from a grating of immersed cylindrical shells, a detailed study of the resonant interaction of A-Wave resonances originating from the shells is conducted. The nature of A-Wave resonances and the effect of center-to-center distance of the shells on these resonances are examined. It is observed that this resonant interaction not only results in the splitting of A-Wave resonances, but also causes an increase in resonance amplitudes. This interaction phenomenon is not seen in Rayleigh, whispering gallery and guided Wave resonances. It is also shown that increasing the angle of Wave incidence to the grating weakens the A-Wave resonant interactions. The numerical results obtained from the mathematical model are compared to experimental results available in the literature for gratings composed of two and three aluminum shells. The numerical results are in very good agreement with their experimental counterparts.

  • Acoustic Wave scattering from infinite cylinders made from functionally graded materials
    Journal of the Acoustical Society of America, 2008
    Co-Authors: Jalil Jamali, Farhang Honarvar, M.h. Naei
    Abstract:

    Functionally graded materials (FGM's) are superheat‐resistive materials which show attractive properties in many applications including furnace liners. FGM's consist of two distinct materials, for example a ceramic and a metal alloy. These two materials are mixed such that the composition of each material changes continuously along a specific direction resulting in a continuous change of microstructure along that direction. The change in microstructure induces chemical, material, and microstructural gradients, and makes functionally graded materials different in behavior from homogeneous materials and traditional composites. In this paper, the scattering of an incident Plane Acoustic Wave from an infinite solid cylinder made from functionally graded materials is studied. Expressions are derived for the far‐field scattered pressure generated by illumination of the infinite FGM cylinder by an infinite Plane Acoustic Wave. The propagation direction of the incident Wave can make an arbitrary angle with the no...

  • scattering of a Plane Acoustic Wave from a transversely isotropic cylinder encased in a solid elastic medium
    Journal of the Acoustical Society of America, 1999
    Co-Authors: A.n. Sinclair, Farhang Honarvar
    Abstract:

    A mathematical model is developed to describe the scattering of a Plane Wave incident at an arbitrary angle on a transversely isotropic cylinder embedded in a solid elastic matrix. The model is based on the normal-mode expansion method, but is complicated by the coupling between the potential functions representing compressional and axially polarized shear Waves. The solid matrix around the cylinder precludes the appearance of the leaky Rayleigh modes that dominate the spectrum of a cylinder immersed in a fluid. Instead, interfacial modes contribute to the scattered spectrum—these modes could be instrumental in the development of a nondestructive evaluation technique for the matrix-to-fiber bonds in a fiber-reinforced composite material. The presence of a solid matrix that supports shearing action leads to scattered compressional Waves, and shear Waves with polarization components in both the axial direction and r-θ Planes. The sensitivity of resonances in each of these scattered Wave components to pertur...

  • Nondestructive evaluation of cylindrical components by resonance Acoustic spectroscopy
    Ultrasonics, 1998
    Co-Authors: Farhang Honarvar, A.n. Sinclair
    Abstract:

    Kari, 2014) 円柱の材料定数の同定のための逆解析がすでに行われている．実験で得られた共鳴周波数が解析と一致するように（？）合わせ込むことで弾性特性を評価する方法をHonarvarが示した． Examples of the applications of resonance Acoustic spectroscopy (RAS) for the purposes of nondestructive evaluation (NDE) and on-line monitoring of the properties of various cylindrical components are presented in this paper. The mathematical equations For the scattering of a Plane Acoustic Wave from isotropic and transversely isotropic cylinders and isotropic clad rods are reviewed. A new technique called material characterization by resonance Acoustic spectroscopy (MCRAS), for the evaluation of the elastic constants of isotropic rods and wires, is introduced. This new technique is compared to the traditional time-of-flight measurement technique. Possible applications of RAS in NDE and on-line monitoring of clad rods are demonstrated using practical examples. The possibility of using RAS for evaluation of axial and transverse properties of fiber-reinforced composite wires and rods, which are transversely isotropic in nature, is discussed. The results indicate that RAS call be used as a tool for NDE and on-line monitoring of various properties of cylindrically-shaped components. (C) 1998 Elsevier Science B.V. All rights reserved.

  • Scattering of an obliquely incident Wave by a transversely isotropic cylinder.
    Journal of the Acoustical Society of America, 1996
    Co-Authors: Farhang Honarvar, Anthony N. Sinclair
    Abstract:

    While the scattering of a Plane Acoustic Wave from a solid isotropic cylinder has been extensively studied for the past several decades, very little has been investigated regarding scattering from anisotropic cylinders. In this paper, the mathematical formulation for the scattering of a Plane Acoustic Wave incident at an arbitrary angle α on an infinite transversely isotropic cylinder is developed. The normal mode solution is based on decoupling of the SH Wave from the P and the SV Waves. The resulting partial differential equations have closed‐form solutions and the scattered pressure field can be calculated at any point outside the cylinder. The solution degenerates to the well‐known simple model for isotropic cylinders in the case of very weak anisotropy. The validity of the mathematical model is verified first by applying it to the familiar case of an isotropic aluminum cylinder. The model is then applied to a transversely isotropic cylinder generated by perturbing various elastic constants of the iso...

Seung Hwan Ko - One of the best experts on this subject based on the ideXlab platform.

  • Laser-induced Acoustic Wave generation/propagation/interaction in water in various internal channels
    Applied Physics A, 2010
    Co-Authors: Seung Hwan Ko, Costas P Grigoropoulos, Nick Kladias, Elias Panides, Gerald A Domoto
    Abstract:

    Short pulsed laser-induced single Acoustic Wave generation, propagation, interaction within a water-filled internal channel are experimentally and numerically studied. A large-area, short-duration, single-Plane Acoustic Wave was generated by the thermoelastic interaction of a homogenized nanosecond pulsed laser beam with a liquid–solid interface and propagated at the speed of sound in water. Laser flash Schlieren photography was used to visualize the transient interaction of the Plane Acoustic Wave in various internal channel structures ((a) sudden expansion and contraction channels, (b) bifurcating channels, (c) gradual contraction wall channels and (d) a cylinder). Fairly good agreement between the experimental results and numerical simulation is observed.

  • laser induced Plane Acoustic Wave generation propagation and interaction with rigid structures in water
    Journal of Applied Physics, 2008
    Co-Authors: Seung Hwan Ko, Nipun Misra, Costas P Grigoropoulos, Nick Kladias, Elias Panides, Gerald A Domoto
    Abstract:

    Short pulsed laser induced single Acoustic Wave generation, propagation, interaction with rigid structures, and focusing in water are experimentally and numerically studied. A large area short duration single Plane Acoustic Wave was generated by the thermoelastic interaction of a homogenized nanosecond pulsed laser beam with a liquid-solid interface and propagated at the speed of sound in water. Laser flash schlieren photography was used to visualize the transient interaction of the Plane Acoustic Wave with various submerged rigid structures [(a) a single block, (b) double blocks, (c) 33° tilted single block, and (d) concave cylindrical Acoustic lens configurations]. Excellent agreement between the experimental results and numerical simulation is observed. Our simulation results demonstrate that the laser induced planar Acoustic Wave can be focused down to several tens of micron size and several bars in pressure.

  • laser induced short Plane Acoustic Wave focusing in water
    Applied Physics Letters, 2007
    Co-Authors: Seung Hwan Ko, Nipun Misra, Costas P Grigoropoulos, Nick Kladias, Elias Panides, Gerald A Domoto
    Abstract:

    Laser induced high frequency Acoustic Wave generation, propagation, and focusing in water are studied. A large area, flat, and short duration Acoustic Wave was generated by the thermoelastic interaction of a homogenized short pulsed laser beam with the liquid-solid interface and propagated at the speed of sound. Laser flash Schlieren photography was used to visualize the transient interaction of the flat Acoustic Wave with a cylindrical concave lens and the subsequent Acoustic Wave focusing. Numerical simulations showed the Acoustic Wave could be focused to several tens of microns in size and 7bars in pressure.

V. V. Shumilova - One of the best experts on this subject based on the ideXlab platform.

  • Plane Acoustic Wave propagation through a composite of elastic and kelvin voigt viscoelastic material layers
    Mechanics of Solids, 2017
    Co-Authors: A. S. Shamaev, V. V. Shumilova
    Abstract:

    The problem of Plane Wave propagation through a Plane composite layer of thickness h is considered. The composite consists of periodically repeated elastic and Kelvin–Voigt viscoelastic material layers, and all layers are either parallel or perpendicular to the incident Wave front. Moreover, it is assumed that the thickness of each separate layer of the composite is much less than the Acoustic Wave length and the thickness h of the entire composite. We study the problem by using a homogenized model of the composite, which allows us to find the reflection and transmission factors and the variation in the sound intensity level as it propagates though the composite layer of thickness h.

  • Plane Acoustic Wave propagation through a composite of elastic and Kelvin–Voigt viscoelastic material layers
    Mechanics of Solids, 2017
    Co-Authors: A. S. Shamaev, V. V. Shumilova
    Abstract:

    The problem of Plane Wave propagation through a Plane composite layer of thickness h is considered. The composite consists of periodically repeated elastic and Kelvin–Voigt viscoelastic material layers, and all layers are either parallel or perpendicular to the incident Wave front. Moreover, it is assumed that the thickness of each separate layer of the composite is much less than the Acoustic Wave length and the thickness h of the entire composite. We study the problem by using a homogenized model of the composite, which allows us to find the reflection and transmission factors and the variation in the sound intensity level as it propagates though the composite layer of thickness h .

  • Passage of a Plane Acoustic Wave through a layered composite with components of elastic and viscoelastic materials
    Acoustical Physics, 2015
    Co-Authors: A. S. Shamaev, V. V. Shumilova
    Abstract:

    The problem of passage of a Plane Acoustic Wave through a flat composite layer of finite thickness is considered. It is assumed that the composite consists of mutually alternate layers of elastic and viscoelastic materials, and all composite layers are either parallel or perpendicular to the incident-Wave front. In addition, the thickness of each separate layer of the composite is considered to be much smaller than both the Acoustic Wavelength and the composite thickness. The formulated problem is investigated using an averaged composite model, which helps to determine the reflection and transmission factors and the change in the sound-intensity level during sound propagation through a composite layer.

  • Reflection of a Plane Acoustic Wave from the interface between an elastic material and a layered elastic-fluid medium
    Fluid Dynamics, 2014
    Co-Authors: A. S. Shamaev, V. V. Shumilova
    Abstract:

    A heterogenous medium consisting of an isotropic elastic material and a viscous compressible fluid is considered. One half of this medium is a continuous elastic material, while the other consists of alternating layers of an elastic material and a fluid. Using an averaged model of the heterogeneous medium the problem of the reflection of a Plane Acoustic Wave from the Plane interface between the continuous elastic material and the layered medium is solved. The reflected and transmitted Wave amplitudes are determined for a medium, whose layers are parallel or perpendicular to the Wave front.

Nipun Misra - One of the best experts on this subject based on the ideXlab platform.

  • laser induced Plane Acoustic Wave generation propagation and interaction with rigid structures in water
    Journal of Applied Physics, 2008
    Co-Authors: Seung Hwan Ko, Nipun Misra, Costas P Grigoropoulos, Nick Kladias, Elias Panides, Gerald A Domoto
    Abstract:

    Short pulsed laser induced single Acoustic Wave generation, propagation, interaction with rigid structures, and focusing in water are experimentally and numerically studied. A large area short duration single Plane Acoustic Wave was generated by the thermoelastic interaction of a homogenized nanosecond pulsed laser beam with a liquid-solid interface and propagated at the speed of sound in water. Laser flash schlieren photography was used to visualize the transient interaction of the Plane Acoustic Wave with various submerged rigid structures [(a) a single block, (b) double blocks, (c) 33° tilted single block, and (d) concave cylindrical Acoustic lens configurations]. Excellent agreement between the experimental results and numerical simulation is observed. Our simulation results demonstrate that the laser induced planar Acoustic Wave can be focused down to several tens of micron size and several bars in pressure.

  • laser induced short Plane Acoustic Wave focusing in water
    Applied Physics Letters, 2007
    Co-Authors: Seung Hwan Ko, Nipun Misra, Costas P Grigoropoulos, Nick Kladias, Elias Panides, Gerald A Domoto
    Abstract:

    Laser induced high frequency Acoustic Wave generation, propagation, and focusing in water are studied. A large area, flat, and short duration Acoustic Wave was generated by the thermoelastic interaction of a homogenized short pulsed laser beam with the liquid-solid interface and propagated at the speed of sound. Laser flash Schlieren photography was used to visualize the transient interaction of the flat Acoustic Wave with a cylindrical concave lens and the subsequent Acoustic Wave focusing. Numerical simulations showed the Acoustic Wave could be focused to several tens of microns in size and 7bars in pressure.