LOCAL PHASE VELOCITY MEASUREMENTS IN PLATES

✍ Scribed by N.H. Clark; S. Thwaites

• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 504 KB
• Volume: 187
• Category: Article
• ISSN: 0022-460X
• DOI: 10.1006/jsvi.1995.0518

✦ Synopsis

A method for measuring local phase velocities in panels, in the range 5-50 kHz, in the presence of a strongly reverberant field, and within 10 cm of structural discontinuities such as ribs, is described. The method gives a resolution of 1-2% and a 2-3% reproduceability. Measurements of the phase velocity as a function of direction for a three-ply and a 12-ply carbon-fibre composite plate are presented. Local values of the elastic properties of individual laminae in the plates, as a function of direction, are calculated from the phase velocities. Small variations in the lay-up angles of some of the laminae are also detected.