Visualization of acoustic particle interaction and agglomeration: Theory evaluation

Hoffmann, T L; Koopmann, G H

doi:10.1121/1.418352

Title: Visualization of acoustic particle interaction and agglomeration: Theory evaluation

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Abstract

In this paper experimentally observed trajectories of particles undergoing acoustically induced interaction and agglomeration processes are compared to and validated with numerically generated trajectories based on existing agglomeration theories. Models for orthokinetic, scattering, mutual radiation pressure, and hydrodynamic particle interaction are considered in the analysis. The characteristic features of the classical orthokinetic agglomeration hypothesis, such as collision processes and agglomerations due to the relative entrainment motion, are not observed in the digital images. The measured entrainment rates of the particles are found to be consistently lower than the theoretically predicted values. Some of the experiments reveal certain characteristics which may possibly be related to mutual scattering interaction. The study`s most significant discovery is the so-called tuning fork agglomeration [T. L. Hoffmann and G. H. Koopmann, J. Acoust. Soc. Am. {bold 99}, 2130{endash}2141 (1996)]. It is shown that this phenomenon contradicts the theories for mutual scattering interaction and mutual radiation pressure interaction, but agrees with the acoustic wake effect model in its intrinsic feature of attraction between particles aligned along the acoustic axis. A model by Dianov {ital et al.} [Sov. Phys. Acoust. {bold 13} (3), 314{endash}319 (1968)] is used to describe this effect based on asymmetric flow fields around particlesmore »« less

Authors:

Hoffmann, T L; Koopmann, G H ^[1]

Center for Acoustics and Vibration, The Pennsylvania State University, 157 Hammond Building, University Park, Pennsylvania 16802 (United States)

Publication Date:: Sun Jun 01 00:00:00 EDT 1997

OSTI Identifier:: 548766

DOE Contract Number:: AC21-89MC26288

Resource Type:: Journal Article

Journal Name:: Journal of the Acoustical Society of America

Additional Journal Information:: Journal Volume: 101; Journal Issue: 6; Other Information: PBD: Jun 1997

Country of Publication:: United States

Language:: English

Subject:: 66 PHYSICS; 42 ENGINEERING NOT INCLUDED IN OTHER CATEGORIES; ACOUSTIC AGGLOMERATORS; AEROSOLS; AGGLOMERATION; PARTICULATES; COLLISIONS; TRAJECTORIES; RADIATION PRESSURE; HYDRODYNAMIC MODEL; COMPUTERIZED SIMULATION

Citation Formats


                    Hoffmann, T L, and Koopmann, G H. Visualization of acoustic particle interaction and agglomeration: Theory evaluation.  United States: N. p., 1997. 
        Web.  doi:10.1121/1.418352.

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                    Hoffmann, T L, & Koopmann, G H. Visualization of acoustic particle interaction and agglomeration: Theory evaluation.  United States.  https://doi.org/10.1121/1.418352

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                    Hoffmann, T L, and Koopmann, G H. 1997.  
        "Visualization of acoustic particle interaction and agglomeration: Theory evaluation".  United States.  https://doi.org/10.1121/1.418352.

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@article{osti_548766,

  title        = {Visualization of acoustic particle interaction and agglomeration: Theory evaluation},

  author       = {Hoffmann, T L and Koopmann, G H},

  abstractNote = {In this paper experimentally observed trajectories of particles undergoing acoustically induced interaction and agglomeration processes are compared to and validated with numerically generated trajectories based on existing agglomeration theories. Models for orthokinetic, scattering, mutual radiation pressure, and hydrodynamic particle interaction are considered in the analysis. The characteristic features of the classical orthokinetic agglomeration hypothesis, such as collision processes and agglomerations due to the relative entrainment motion, are not observed in the digital images. The measured entrainment rates of the particles are found to be consistently lower than the theoretically predicted values. Some of the experiments reveal certain characteristics which may possibly be related to mutual scattering interaction. The study`s most significant discovery is the so-called tuning fork agglomeration [T. L. Hoffmann and G. H. Koopmann, J. Acoust. Soc. Am. {bold 99}, 2130{endash}2141 (1996)]. It is shown that this phenomenon contradicts the theories for mutual scattering interaction and mutual radiation pressure interaction, but agrees with the acoustic wake effect model in its intrinsic feature of attraction between particles aligned along the acoustic axis. A model by Dianov {ital et al.} [Sov. Phys. Acoust. {bold 13} (3), 314{endash}319 (1968)] is used to describe this effect based on asymmetric flow fields around particles under Oseen flow conditions. It is concluded that this model is consistent with the general characteristics of the tuning fork agglomerations, but lacks certain refinements with respect to accurate quantification of the effect. {copyright} {ital 1997 Acoustical Society of America.}},

  doi          = {10.1121/1.418352},

  url          = {https://www.osti.gov/biblio/548766},
  journal      = {Journal of the Acoustical Society of America},
number       = 6,

  volume       = 101,

  place        = {United States},

  year         = {Sun Jun 01 00:00:00 EDT 1997},

  month        = {Sun Jun 01 00:00:00 EDT 1997}

}

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