### ASA 130th Meeting - St. Louis, MO - 1995 Nov 27 .. Dec 01

## 2pSA6. Acoustic interaction with wedge-shaped structures.

**Andrew N. Norris
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*Dept. of Mech. and Aerospace Eng., Rutgers Univ., Piscataway, NJ
08855-0909
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This paper will review recent developments in solving canonical structural
acoustics problems involving wedgelike structures composed of plates and
membranes. The two cases considered are (i) a membrane held taut over a line
constraint, and (ii) two semi-infinite thin plates welded together to form a
wedge. The wedge-shaped structures are subject to unilateral fluid loading from
an acoustic fluid. The method of Malyuzhinets, which was used in the 1950s for
the purpose of dealing with simple impedance-type boundary conditions on the
wedge faces, has recently been significantly developed by A.V. Osipov, who has
shown how it can be successfully applied to these structural acoustics problems.
The central idea of the Malyuzhinets/Osipov method is to express the acoustic
pressure using a generalized Sommerfeld integral, similar to a Laplace
transform. The main analytical steps in the solution will be discussed, and some
numerical results will be presented. The plate structure is particularly
interesting because both subsonic flexural and nonleaky supersonic structural
waves are excited at the vertex by an incident acoustic wave. Interesting
asymptotics emerge when the wedge angle described by the fluid is almost 180[sup
o] or 360[sup o]. [Work supported by ONR.]