### ASA 124th Meeting New Orleans 1992 October

## 5aSA3. Energy exchange between the coupled media of impulsively excited
fluid-filled cylinders.

**Chris R. Fuller
**

**
Bertrand J. Brevart
**

**
**
*Vibration and Acoust. Labs., Dept. of Mech. Eng., Virginia Polytech. Inst.
and State Univ., Blacksburg, VA 24061
*

*
*
The time domain response of an infinite fluid-filled pipe to an impulsive
line force of various azimuthal distribution (circumferential modes 0 and 1) is
first derived, based on the Donnell--Mushtari shell equations fully coupled to
interior acoustic field and computing a double Fourier integration in the wave
number and the frequency domain. The transient radial displacement of the shell
is then used to compute the coupled pressure field in the fluid and investigate
the instantaneous intensity vectors in the near field closely hugging the wall.
These vectors, evaluated at several distances from the input force, give
insight into the exchange of energy between the structure and the fluid as the
various waves propagate through the system. [Work supported by ONR.]