Thomas L. Hoffmann
Ctr. for Acoust. and Vib., Penn State Univ., 157 Hammond Bldg., University Park, PA 16802
A numerical and experimental study is presented to visualize trajectories
of a pair of particulates entrained in an acoustic field. A numerical scheme is
developed for determinating the relative path of the particles under the
influence of orthokinetic, scattering, and hydrodynamic forces. The importance
of the different interaction mechanisms is evaluated for varying frequencies
and sound-pressure levels. A bench-top experimental setup is used to visualize
actual particle trajectories in a sound field with a high-speed video system.
These trajectories are then mapped to determine the actual relative particle
path of one particle against the other. The results of a comparison between the
numerical simulations and the experimental visualizations are used to assess
the validity of the existing theoretical models in respect to orthokinetic,
scattering, and hydrodynamic interaction mechanisms.