### ASA 129th Meeting - Washington, DC - 1995 May 30 .. Jun 06

## 2aSA11. Acoustic and flexural wave scattering from a three member
junction.

**Douglas A. Rebinsky
**

**
Andrew N. Norris
**

**
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*Dept. of Mech. and Aerospace Eng., Rutgers Univ., Piscataway, NJ
08855-0909
*

*
*
A three member junction is formed by a pair of semi-infinite plates in
contact with fluid on one side and a mechanical structure on the other. The
latter is described by an impedance matrix and the plates are modeled by the
classical theory of flexure. The scattering problem for oblique incidence is
solved using the impedance matrix for the plate junction without the
attachment. This is accomplished using the Wiener--Hopf technique to solve the
dual integral equations for the unknown pressure on the plates. Explicit
formulae are obtained for the pressure transform, and corresponding explicit
and relatively simple expressions are given for the various diffraction
coefficients associated with the fluid/structure interaction. Numerical results
for the redistribution of energy from flexural to flexural plus acoustic at a
thickness discontinuity will be discussed in detail with respect to frequency
and angle of incidence including the effect of various critical angles. It is
verified that the general solution reduces to that for a pair of plates with
clamped and welded junction conditions as limiting cases when the frame
impedance is zero and infinite. [Work supported by ONR.]