Induced acoustic radiation force and torque on a pulsating cylindrical source near a planar rigid half-space boundary

摘要

In this contribution, the phenomenon of wall-induced acoustic radiation force and torque on an active cylindrically radiating acoustic source, undergoing axisymmetric or asymmetric harmonic vibrations (i.e., using a superposition of different vibrational source modes) near a flat rigid boundary in a non-viscous fluid is demonstrated using the modal expansion method, the translational addition theorem, and the method of images. These physical phenomena arise due to the multiple interactions with the boundary. Assuming axisymmetric or asymmetric modal oscillations of the source, conditions are found where the longitudinal and transversal radiation force functions as well as the axial torque component vanish, achieving complete translational or rotational motion suppression of the pulsating source. These components also take positive or negative values, depending on the source size and distance from the flat rigid wall, suggesting pushing or pulling effects towards the boundary, and possible source rotation clockwise or counter-clockwise. The analytical formalism developed here can be helpful in predicting emergent phenomena related to applications in underwater acoustics, particle manipulation of active carriers or ultrasound contrast agents located near a boundary, and possibly other applications in fluid dynamics and related topics. Published by AIP Publishing.