Prof. Thomas DeLillo

Wichita State University

"An Overview of Computational Methods for Inverse Problems in Acoustics"

We will give an overview of various methods that have been used for the problem of locating sources of acoustical noise and structural vibrations by taking pressure measurements in the sound field. These methods are formulated as inverse problems for the Helmholtz equation and require regularization. The methods reviewed will include: the Nearfield Acoustic Holography (NAH) methods developed by E.G. Williams and his colleagues and based on evanescent expansions of the Neumann Green functions for separable geometries; the Helmholtz Equation Least Squares (HELS) method developed by S. F. Wu and his colleagues and based on least squares fits of pressure data by expansions in spherical harmonics; and various direct and indirect integral equation formulations, such as those based on single layer potentials and the Helmholtz-Kirchhoff integral equation.

Friday, November 9, 2001
3:00 PM in 335 Jabara Hall

Please join us for refreshments before the lecture at 2:30p.m. in room 353 Jabara Hall.

[ Fall 2001]