Acoustic radiation torque and the conservation of angular momentum (L)

作者：Zhang Likun^*; Marston Philip L

来源：Journal of the Acoustical Society of America, 2011, 129(4): 1679-1680.

DOI：10.1121/1.3560916

This note concerns the evaluation of the static acoustic radiation torque exerted by an acoustic field on a scatterer immersed in a nonviscous fluid based on far-field scattering. The radiation torque is expressed as the integral of the time-averaged flux of angular momentum over a spherical surface far removed from the scattering object with its center at the centroid of the object. That result was given previously [G. Maidanik, J. Acoust. Soc. Am. 30, 620-623 (1956)]. Another expression given recently [Z. W. Fan et al., J. Acoust. Soc. Am. 124, 2727-2732 (2008)] is simplified to this formula. Comments are made on obtaining it directly from the general theorem of angular momentum conservation in the integral form.

• 出版日期2011-4