Calculation and optimization of acoustic radiation force produced by a two-dimensional transducer array

Abstract

The beam-shape coefficients of a focused sound field from a two-dimensional transducer array are obtained by using the translational addition theorem for spherical functions, and the acoustic radiation force function of a sphere is given in terms of the beam-shape coefficients and the scattering coefficients. The numerical results of acoustic radiation force function show that when the radius of the sphere is much smaller than the acoustic wavelength, the acoustic radiation force function increases sharply with the increase in the radius, while it begins to decrease as the radius continues to increase. Increasing the vibration frequency of the transducer, the array element spacing and the number of elements will enhance the directivity of the acoustic beam and make the acoustic radiation force distribution much more concentrated at the bottom of the sphere. Through optimization of acoustic radiation force distribution by adjusting the phase distribution of the transducer array, the acoustic radiation force distribution range at the bottom of the sphere becomes wider.