Nonlinear Interaction of Acoustic Waves with a Spheroidal Particle: Radiation Force and Torque Effects

Mean-acoustic fields exerted on a subwavelength axisymmetric particle

“…The acoustic radiation torque τ rad p generated by an acoustic field relative to the p-frame is expressed by 11,32…”

“…4 Recently, the meanacoustic field model was also extended for spheroidal particles. 32 This article proposes a semi-analytical approach to describe the mean-acoustic fields interacting with an arbitrary axisymmetric particle in Newtonian thermoviscous fluids. The mean fields are related to the coefficients of the monopole and dipole modes of the scattered waves.…”

Equivalence between angular spectrum-based and multipole expansion-based formulas of the acoustic radiation force and torque

“…Silva depending on the indexes of (n, m) with several numerical computation for arbitrary-sized nonspherical shapes by a semi-analytical T-matrix method 21,22,36 . For a rigid spheroidal particle in the so-called long-wavelength limit, Silva and colleagues gives the A m n with the Taylor expansion up to the dipole (n = 1) in spheroidal coordinates 45 and obtain concise analytical ARF and ART expressions using the partial wave expansion 46 . Note also that the overall formulas discussed in the present work are generally applied for a particle in an ideal fluid but are still applicable for a particle in a viscous fluid if the viscous effect in the fluid can be accounted in the expression of scattering (partial wave) coefficients 15,47 .…”

“…(11) AND FORMULAS BY SAPOZH-NIKOV & BAILEYBy substituting Eq. (7) into (13), we can prove that the three components of ARF formulas for a sphere (with A m n = A n ) are equivalent to those in terms of H nm by Sapozhnikov & Bailey [see Eqs (46)(47)(48). in Ref 16.…”

Acoustic radiation force and torque on spheroidal particles in an ideal cylindrical chamber

“…Our approach is based on the exact expressions of these fields to the dipole approximation as obtained in Ref. 42. We transform the radiation force and torque expressions to a fixed laborat ory frame in which the particle dynamics can be analyzed.…”