Author: George Vladimir Frisk
Publisher:
ISBN:
Category : Rayleigh waves
Languages : en
Pages : 186
Book Description
The connection between creeping wave and flat surface wave theory is established by investigating the limit of acoustic scattering from a solid elastic cylinder, imbedded in a fluid, whose radius tends to infinity. First, the asymptotic behavior of the complex circumferential wave numbers is calculated by substituting the appropriate Debye- or Airy-type asymptotic expansions into the 3 x 3 secular determinant and solving it using iterative techniques. It is found that, in the limit of infinite cylinder radius, the wave numbers of the Rayleigh and Stoneley modes tend toward those of the Rayleigh and Stoneley waves on a flat elastic half-space, while the Franz mode wave numbers tend toward the wave number of sound in the fluid. The longitudinal and transverse Whispering Gallery mode wave numbers tend toward the longitudinal and transverse wave numbers in the solid. Graphical results are presented for an aluminum cylinder in water (and in one case, also in vacuum) and show good agreement with existing numerical results. Then, using the Watson-Sommerfeld transformation, the limiting behavior of the solution to the problem of the scattering of a cylindrical wave from a cylinder whose radius tends to infinity is investigated. Using the analytic expressions for the creeping wave numbers, it is shown that the residue sums corresponding to the different classes of circumferential waves tend individually toward the different types of surface waves found on the flat surface.
Creeping Waves and Lateral Waves in Acoustic Scattering by Large Elastic Cylinders
Author: George Vladimir Frisk
Publisher:
ISBN:
Category : Rayleigh waves
Languages : en
Pages : 186
Book Description
The connection between creeping wave and flat surface wave theory is established by investigating the limit of acoustic scattering from a solid elastic cylinder, imbedded in a fluid, whose radius tends to infinity. First, the asymptotic behavior of the complex circumferential wave numbers is calculated by substituting the appropriate Debye- or Airy-type asymptotic expansions into the 3 x 3 secular determinant and solving it using iterative techniques. It is found that, in the limit of infinite cylinder radius, the wave numbers of the Rayleigh and Stoneley modes tend toward those of the Rayleigh and Stoneley waves on a flat elastic half-space, while the Franz mode wave numbers tend toward the wave number of sound in the fluid. The longitudinal and transverse Whispering Gallery mode wave numbers tend toward the longitudinal and transverse wave numbers in the solid. Graphical results are presented for an aluminum cylinder in water (and in one case, also in vacuum) and show good agreement with existing numerical results. Then, using the Watson-Sommerfeld transformation, the limiting behavior of the solution to the problem of the scattering of a cylindrical wave from a cylinder whose radius tends to infinity is investigated. Using the analytic expressions for the creeping wave numbers, it is shown that the residue sums corresponding to the different classes of circumferential waves tend individually toward the different types of surface waves found on the flat surface.
Publisher:
ISBN:
Category : Rayleigh waves
Languages : en
Pages : 186
Book Description
The connection between creeping wave and flat surface wave theory is established by investigating the limit of acoustic scattering from a solid elastic cylinder, imbedded in a fluid, whose radius tends to infinity. First, the asymptotic behavior of the complex circumferential wave numbers is calculated by substituting the appropriate Debye- or Airy-type asymptotic expansions into the 3 x 3 secular determinant and solving it using iterative techniques. It is found that, in the limit of infinite cylinder radius, the wave numbers of the Rayleigh and Stoneley modes tend toward those of the Rayleigh and Stoneley waves on a flat elastic half-space, while the Franz mode wave numbers tend toward the wave number of sound in the fluid. The longitudinal and transverse Whispering Gallery mode wave numbers tend toward the longitudinal and transverse wave numbers in the solid. Graphical results are presented for an aluminum cylinder in water (and in one case, also in vacuum) and show good agreement with existing numerical results. Then, using the Watson-Sommerfeld transformation, the limiting behavior of the solution to the problem of the scattering of a cylindrical wave from a cylinder whose radius tends to infinity is investigated. Using the analytic expressions for the creeping wave numbers, it is shown that the residue sums corresponding to the different classes of circumferential waves tend individually toward the different types of surface waves found on the flat surface.
Numerical Discussion of Creeping Acoustical Waves Around Cylinders. Sound Scattering by Elastic Cylindrical Shells
Author: H. Uberall
Publisher:
ISBN:
Category :
Languages : en
Pages : 29
Book Description
The report presents the solution for the scattered field corresponding to a plane sound wave incident upon an infinite elastic circular-cylindrical concentric shell, imbedded in a fluid and enclosing another fluid. The results are shown to contain the known special cases of fluid and elastic solid cylinders. Furthermore, limiting expressions for long wavelengths are obtained in special cases. The second part of this report is a sequel to a previous report (AD-625 793) 'Pulsed Creeping Waves in Acoustics', which discussed diffraction of sound waves and pulses by cylinders. Graphical illustrations are presented of some aspects of the creeping waves, in particular their velocities and damping for rigid and soft cylinders, the backscattering cross section for rigid cylinders, and the shape of the head of the diffracted pulses. It is found that only very few creeping waves already give an excellent approximation to the exact solution for large and even moderately large values of ka. (Author).
Publisher:
ISBN:
Category :
Languages : en
Pages : 29
Book Description
The report presents the solution for the scattered field corresponding to a plane sound wave incident upon an infinite elastic circular-cylindrical concentric shell, imbedded in a fluid and enclosing another fluid. The results are shown to contain the known special cases of fluid and elastic solid cylinders. Furthermore, limiting expressions for long wavelengths are obtained in special cases. The second part of this report is a sequel to a previous report (AD-625 793) 'Pulsed Creeping Waves in Acoustics', which discussed diffraction of sound waves and pulses by cylinders. Graphical illustrations are presented of some aspects of the creeping waves, in particular their velocities and damping for rigid and soft cylinders, the backscattering cross section for rigid cylinders, and the shape of the head of the diffracted pulses. It is found that only very few creeping waves already give an excellent approximation to the exact solution for large and even moderately large values of ka. (Author).
Acoustic Interactions with Submerged Elastic Structures
Author: Ard‚shir Guran
Publisher: World Scientific
ISBN: 9789812778536
Category : Mathematics
Languages : en
Pages : 522
Book Description
This series of volumes constitutes an outstanding collection of contributions by the most active research workers in the area of acoustics and mechanics. It brings the reader up to date on the status of the various aspects of research in this field. The volumes should preserve their value for a long time, as they represent a monument to the achievements of human research capabilities in the underwater-acoustics aspects of the environment.
Publisher: World Scientific
ISBN: 9789812778536
Category : Mathematics
Languages : en
Pages : 522
Book Description
This series of volumes constitutes an outstanding collection of contributions by the most active research workers in the area of acoustics and mechanics. It brings the reader up to date on the status of the various aspects of research in this field. The volumes should preserve their value for a long time, as they represent a monument to the achievements of human research capabilities in the underwater-acoustics aspects of the environment.
Evaluation of the Relative Importance of Circumferential Or Creeping Waves in the Acoustic Scattering from Rigid and Elastic Solid Cylinders and from Cylindrical Shells
Author: Louis R. Dragonette
Publisher:
ISBN:
Category : Cylinders
Languages : en
Pages : 68
Book Description
The relationship is determined between predicted circumferential waves on cylinders and the normal-mode series solution for the acoustic scattering by submerged metal cylinders. Specific circumferential waves are linked to the free modes of vibration of the cylinder, and this identification is used to experimentally detect the Rayleigh surface wave at low ka. Circumferential waves on thin cylindrical shells are demonstrated to closely follow prediction based on Lamb theory for flat plates. (Author).
Publisher:
ISBN:
Category : Cylinders
Languages : en
Pages : 68
Book Description
The relationship is determined between predicted circumferential waves on cylinders and the normal-mode series solution for the acoustic scattering by submerged metal cylinders. Specific circumferential waves are linked to the free modes of vibration of the cylinder, and this identification is used to experimentally detect the Rayleigh surface wave at low ka. Circumferential waves on thin cylindrical shells are demonstrated to closely follow prediction based on Lamb theory for flat plates. (Author).
Report of NRL Progress
Author: Naval Research Laboratory (U.S.)
Publisher:
ISBN:
Category : Naval research
Languages : en
Pages : 594
Book Description
Publisher:
ISBN:
Category : Naval research
Languages : en
Pages : 594
Book Description
A Creeping Wave Description of Sound Scattering from Elastic Cylinders
Author: Richard Doolittle
Publisher:
ISBN:
Category : Scattering (Physics)
Languages : en
Pages : 100
Book Description
Publisher:
ISBN:
Category : Scattering (Physics)
Languages : en
Pages : 100
Book Description
Ocean and Seabed Acoustics
Author: George V. Frisk
Publisher: Pearson Education
ISBN: 0132441543
Category : Technology & Engineering
Languages : en
Pages : 391
Book Description
Respected scientist and educator George V. Frisk draws on his extensive professional experience to demonstrate how the ocean environment provides an excellent setting in which to display general principles of wave propagation that are also applicable to other areas of wave physics. Ocean and Seabed Acoustics proceeds with a derivation of elementary solutions to the wave equation in free space and then progressively addresses problems of increasing complexity. This book concludes with a discussion of acoustic wave propagation due to a point source in an inhomogeneous waveguide with lossy boundaries.
Publisher: Pearson Education
ISBN: 0132441543
Category : Technology & Engineering
Languages : en
Pages : 391
Book Description
Respected scientist and educator George V. Frisk draws on his extensive professional experience to demonstrate how the ocean environment provides an excellent setting in which to display general principles of wave propagation that are also applicable to other areas of wave physics. Ocean and Seabed Acoustics proceeds with a derivation of elementary solutions to the wave equation in free space and then progressively addresses problems of increasing complexity. This book concludes with a discussion of acoustic wave propagation due to a point source in an inhomogeneous waveguide with lossy boundaries.
Scientific and Technical Aerospace Reports
High Frequency and Pulse Scattering
Author: Allan D. Pierce
Publisher: Academic Press
ISBN: 1483257703
Category : Science
Languages : en
Pages : 340
Book Description
High Frequency and Pulse Scattering investigates high frequency and pulse scattering, with emphasis on the phenomenon of echoes from objects. Geometrical and catastrophe optics methods in scattering are discussed, along with the scattering of sound pulses and the ringing of target resonances. Caustics and associated diffraction catastrophes are also examined. Comprised of two chapters, this volume begins with a detailed account of geometrically based approximation methods in scattering theory, focusing on waves transmitted through fluid and elastic scatterers and glory scattering; surface ray representations of scattering by shells and other smooth objects; and caustics and associated diffraction catastrophes. The second chapter deals with the relation between sound pulses and the vibrational spectra of elastic submerged objects. The theory of the scattering of sound pulses from elastic and impenetrable objects is described, together with the theory of surface wave pulses. Target resonances and the singularity expansion method are also analyzed. This book will be of interest to physicists.
Publisher: Academic Press
ISBN: 1483257703
Category : Science
Languages : en
Pages : 340
Book Description
High Frequency and Pulse Scattering investigates high frequency and pulse scattering, with emphasis on the phenomenon of echoes from objects. Geometrical and catastrophe optics methods in scattering are discussed, along with the scattering of sound pulses and the ringing of target resonances. Caustics and associated diffraction catastrophes are also examined. Comprised of two chapters, this volume begins with a detailed account of geometrically based approximation methods in scattering theory, focusing on waves transmitted through fluid and elastic scatterers and glory scattering; surface ray representations of scattering by shells and other smooth objects; and caustics and associated diffraction catastrophes. The second chapter deals with the relation between sound pulses and the vibrational spectra of elastic submerged objects. The theory of the scattering of sound pulses from elastic and impenetrable objects is described, together with the theory of surface wave pulses. Target resonances and the singularity expansion method are also analyzed. This book will be of interest to physicists.
Scattering of Acoustic and Elastic Waves by Surfaces of Arbitrary Shape
Author: Robert Peter Banaugh
Publisher:
ISBN:
Category : Elastic waves
Languages : en
Pages : 196
Book Description
Publisher:
ISBN:
Category : Elastic waves
Languages : en
Pages : 196
Book Description