Acoustic point source scattering by a spherical elastic shell submerged beneath a free surface

1996 ◽  
Vol 99 (5) ◽  
pp. 2720-2726 ◽  
Author(s):  
H. Huang ◽  
G. C. Gaunaurd
Keyword(s):  
Free Surface ◽  
Point Source ◽  
Elastic Shell ◽  
Spherical Elastic Shell

Scattering of a Plane Acoustic Wave by a Spherical Elastic Shell Near a Free Surface

1995 ◽  
Author(s):  
H. Huang ◽  
G. C. Gaunaurd
Keyword(s):  
Free Surface ◽  
Separation Of Variables ◽  
Mathematical Problem ◽  
Elastic Shell ◽  
Plane Waves ◽  
Spherical Wave ◽  
Acoustic Scattering ◽  
Scattered Wave ◽  
Image Method ◽  
Spherical Elastic Shell

Abstract The acoustic scattering by a submerged spherical elastic shell near a free surface, and insonified by plane waves at arbitrary angles of incidence is analyzed in an exact fashion using the classical separation of variables technique. To satisfy the boundary conditions at the free surface as well as on the surface of the spherical elastic shell, the mathematical problem is formulated using the image method. The scattering wave fields are expanded in terms of the classical modal series of spherical wave functions utilizing the translational addition theorem. Quite similar to the problem of scattering by multiple spheres, the numerical computation of the scattered wave pressure involves the solution of an ill-conditioned complex matrix system the size of which depends on how many terms of the modal series are required for convergence. This in turn depends on the value of the frequency, and the proximity of the spherical elastic shell to the free surface. The ill-conditioned matrix equation is solved using the Gauss-Seidel iteration method and Twersky’s method of successive iteration double checking each other. Backscattered echoes from the spherical elastic shell are extensively calculated and displayed. The result also demonstrates that the large amplitude low frequency resonances of the echoes of the submerged elastic shell shift upward with proximity to the free surface. This can be attributed to the decrease of added mass for the shell vibration.

Free Surface Green Function Research Based on Cloud Computing for Ship Movement on the Water

2013 ◽  
Vol 344 ◽  
pp. 27-30
Author(s):  
Cong Zhang ◽  
Xin Wang ◽  
Jie Zhao ◽  
She Sheng Zhang
Keyword(s):  
Cloud Computing ◽  
Free Surface ◽  
Green Function ◽  
Point Source ◽  
Calculation Procedure ◽  
Green Functions ◽  
Two Dimensional ◽  
Surface Green Function ◽  
Cloud Computation ◽  
Control Equation

In order to easy use Green function on cloud computation, the author consider control equation of point source with free surface, and discuss the representation of Green function on cloud computation, and then propose the discrete calculation expression as well as the calculation procedure. Finally, the two-dimensional graphics of the Green functions real and imaginary parts are plotted.

A Small Axisymmetric Obstacle in the Presence of an Underwater Point-Source Field

1997 ◽  
Vol 05 (03) ◽  
pp. 243-263 ◽  
Author(s):  
A. Charalambopoulos ◽  
G. Dassios ◽  
P. Ergatis
Keyword(s):  
Free Surface ◽  
Point Source ◽  
Pressure Field ◽  
Vertical Line ◽  
Source Field ◽  
Floating Object ◽  
Smooth Objects ◽  
Special Case

A small, acoustically hard and axisymmetric object is placed in a deep homogeneous sea environment with a hard plane bottom. The free surface of the sea is assumed to be soft. The source and the receiver are placed on the same vertical line, far away from the object. Given the positions of the source and the receiver, two problems are solved: the determination of the pressure field at the receiver from the position and the shape of the object, and the determination of the position and the shape of the object from the pressure field at the receiver. The special case of smooth objects generated by the rotation of differentiable curves is studied. We provide results for the case of a floating object and for the case of an object or a boss at the bottom of the sea.

scholarly journals Influence of Point Source on Free Surface of Two-Layer Liquid

2012 ◽  
Author(s):  
В.Н. Носов ◽  
◽  
А.А. Савин ◽  
А.С. Савин ◽  
◽  
...  
Keyword(s):  
Free Surface ◽  
Point Source
Sign in / Sign up

Export Citation Format

Share Document