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Measurement of Chladni Mode Shapes with an Optical Lever Method
Published on: June 5, 2020
Comment on plate modal wavenumber transforms in Sound and structural vibration [Academic Press (1987, 2007)] (L)
Micah R Shepherd1, Stephen A Hambric
1Graduate Program in Acoustics, Applied Research Laboratory, The Pennsylvania State University, P.O. Box 30, State College, Pennsylvania 16804, USA. mrs30@arl.psu.edu
Abstract:
The wavenumber transform for rectangular, simply supported, isotropic thin plates has been rederived to correct a technical error found in the text Sound and Structural Vibration (Academic Press, 1985/2007) by Fahy/Fahy and Gardonio. The text states that the modal wavenumber corresponds to the peak of the wavenumber spectrum. While this is approximately true for higher-order modes, it does not hold for lower-order modes due to coupling between positive and negative wavenumber energy. The modal wavenumber is shown to be related to the zeros in the wavenumber spectrum by an integer multiple of 2π normalized by the plate length.
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