title: Guided plate wave scattering at vertical stiffeners and its effect on source location.
abstract: This paper examines guided wave transmission characteristics of plate stiffeners and their influence on the performance of acoustic noise source location. The motivation for this work is the detection of air leaks in manned spacecraft. The leaking air is turbulent and generates noise that can be detected by a contact-coupled acoustic array to perform source location and find the air leak. Transmission characteristics of individual integral stiffeners are measured across a frequency range of 50-400kHz for both high and low aspect-ratio rectangular stiffeners, and comparisons are made to model predictions which display generally good agreement. It is demonstrated that operating in frequency ranges of high plate wave stiffener transmission significantly improves the reliability of noise source location in the plate. A protocol is presented to enable the selection of an optimal frequency range for leak location.
authors.affiliation: Center for Nondestructive Evaluation and Aerospace Engineering Department, Iowa State University, Ames, IA 50011, USA. rreusser@iastate.edu
authors.forename: R S
authors.initials: RS
authors.lastname: Reusser
authors.forename: D E
authors.initials: DE
authors.lastname: Chimenti
authors.forename: R A
authors.initials: RA
authors.lastname: Roberts
authors.forename: S D
authors.initials: SD
authors.lastname: Holland