Point Sources and Waves With Cylindrical Symmetry
While Lamb's analysis assumed a straight wavefront, it has been shown* that the same characteristic equations apply to axisymmetric plate waves (e.g. waves propagating with circular wavefronts from point sources, like ripples from a stone dropped into a pond). The difference is that whereas the "carrier" for the straight wavefront is a sinusoid, the "carrier" for the axisymmetric wave is a Bessel function. The Bessel function takes care of the singularity at the source, then converges towards sinusoidal behavior at great distances.
- Klaes, M, in Journées d'Etudes sur l'Emission Acoustique, INSA de Lyon (France), 1978.
Read more about this topic: Lamb Waves
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