کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1758789 | 1523212 | 2015 | 6 صفحه PDF | دانلود رایگان |
• An orthogonality-relation based method is applied to separate Lamb modes from signals.
• Finite element simulations and experiments were performed to validate the proposed idea.
• 3D Scanning Laser Doppler Vibrometer is used to measure edge 2D displacements simultaneously.
• The technique is robust against errors in displacement amplitudes and material input parameters.
In this study the orthogonality relation-based method for post-processing finite element (FE) predictions and experimental measurements is applied in order to separate Lamb modes at a plate edge at normal incidence. The scattered wave field from the free edge is assumed to be a superposition of all the eigenmodes of an infinite plate. The eigenmode amplitudes of the reflected wave field are determined by implementing the orthogonality-based method on the measured plate edge displacements. Overlapping wavepackets of Lamb modes at a plate edge are simulated by using the FE model and the experiment in the case of an incident S0 mode in a plate with a notch. In the experiment a 3D Scanning Laser Doppler Vibrometer (3D SLDV) (Johansmann and Sauer, 2005) is used to measure 3 dimensional vibrations and thus the edge two-dimensional displacement components simultaneously. It is demonstrated that it is possible to extract signals of various propagating and non-propagating modes in time-domain. The influences of the errors in practical measurements on the extraction procedure have also been studied.
Journal: Ultrasonics - Volume 57, March 2015, Pages 90–95