The rotation and translation of non-spherical particles in homogeneous isotropic turbulence

Margaret L. Byron

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arXiv · 1506.00478

The rotation and translation of non-spherical particles in homogeneous isotropic turbulence

Margaret L. Byron

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Abstract

The motion of particles suspended in environmental turbulence is relevant to many scientific fields, from sediment transport to biological interactions to underwater robotics. At very small scales and simple shapes, we are able to completely mathematically describe the motion of inertial particles; however, the motion of large aspherical particles is significantly more complex, and current computational models are inadequate for large or highly-resolved domains. Therefore, we seek to experimentally investigate the coupling between freely suspended particles and ambient turbulence. A better understanding of this coupling will inform not only engineering and physics, but the interactions between small aquatic organisms and their environments. We explore the roles of shape and buoyancy on the motion of passive particles in turbulence, and allow these particles to serve as models for meso-scale aquatic organisms. The results of this study will allow us to more accurately predict the motion of aspherical particles, giving new insights into oceanic carbon cycling, industrial processes, and other important topics. This analysis will also shed light onto biological questions of navigation, reproduction, and predator-prey interaction by quantifying the turbulence-driven behavior of meso-scale aquatic organisms, allowing researchers to sift out passive vs. active effects in a behaving organism. Lastly, processes that are directly dependent on particle dynamics (e.g., sediment transport, industrial processes) will be informed by our results.

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Margaret L. Byron. 2015-06-01. The rotation and translation of non-spherical particles in homogeneous isotropic turbulence. https://arxiv.org/abs/1506.00478

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