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Guided plate wave scattering at vertical stiffeners and its effect on source location
R S Reusser1, D E Chimenti, R A Roberts
1Center for Nondestructive Evaluation and Aerospace Engineering Department, Iowa State University, Ames, IA 50011, USA. rreusser@iastate.edu
Ultrasonics
|January 17, 2012
Summary
This study enhances acoustic noise source location for detecting air leaks in spacecraft. Optimizing guided wave transmission through plate stiffeners improves leak detection reliability.
Area of Science:
- Acoustics
- Structural Mechanics
- Wave Propagation
Background:
- Air leaks in manned spacecraft pose a significant safety risk.
- Turbulent airflow from leaks generates detectable acoustic noise.
- Accurate noise source location is crucial for timely leak detection and repair.
Purpose of the Study:
- To investigate guided wave transmission characteristics of plate stiffeners.
- To determine the influence of these characteristics on acoustic noise source location performance.
- To develop a protocol for optimizing frequency selection for air leak detection.
Main Methods:
- Measured guided wave transmission across a 50-400kHz frequency range for rectangular stiffeners.
- Compared experimental measurements with model predictions.
- Evaluated the impact of transmission characteristics on noise source location reliability.
Main Results:
- Generally good agreement between measured and predicted transmission characteristics.
- Demonstrated that high plate wave stiffener transmission frequencies significantly enhance noise source location reliability.
- Identified optimal frequency ranges for improved leak detection.
Conclusions:
- Guided wave transmission through plate stiffeners is a critical factor in acoustic source localization.
- Selecting appropriate operating frequencies based on transmission characteristics optimizes air leak detection in spacecraft.
- The presented protocol aids in selecting optimal frequencies for reliable leak location.
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