## 3pSA5. Development of a mid-frequency definition and appropriate analysis techniques.

### Session: Wednesday Afternoon, May 15

### Time: 1:30

**Author: John E. Huff, Jr.**

**Location: School of Mech. Eng., Purdue Univ., 1077 Herrick Labs., West Lafayette, IN 47907-1077**

**Author: Guglielmo Rabbiolo**

**Author: Robert J. Bernhard**

**Author: Fabio A. Milner**

**Location: Purdue Univ., West Lafayette, IN 47907**

**Abstract:**

From experimental data collected on ensembles and from analytical
verification studies of structural acoustic systems, it is apparent that there
is a mid-frequency range where dominant structural acoustic responses cannot be
sufficiently described deterministically or statistically. The focus of this
presentation is to describe work to derive a general and rigorous definition for
the frequency limits of the mid-frequency range. The statistical behavior of
system response in this range is described through the analysis of the
analytical expressions for the displacement of Bernoulli--Euler beams.
Additionally, work to develop a numerical analysis technique which can be
implemented in a finite element formulation is discussed and the possible
connections between it and current techniques for energy flow analysis in the
high-frequency range are made.

from ASA 131st Meeting, Indianapolis, May 1996