Elastic orbital angular momentum transfer from an elastic pipe to a fluid

Abstract Research into the orbital angular momentum carried by helical wave-fronts has been dominated fields of electromagnetism and acoustics, owing to its practical utility in sensing, communication, tweezing. Despite huge research effort across wave community, only recently elastic theoretically shown exhibit similar properties. Here we experimentally observe transfer from a hollow pipe fluid which is partially submerged, an analogue Durnin’s slit-ring experiment for optical beams. This achieved coupling dilatational component guided flexural waves with pressure field fluid; circumferential distribution normal stress acts as continuous phased source resulting generation Bessel-like acoustic demonstration implications future new regime waves, well providing alternative method excite beams that carry could create paradigm shift