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arXiv · 2403.13943

Complex Dynamics of an Acoustically Levitated Fluid Droplet Captured by a Low-Order Immersed Boundary Method

Jacqueline B. Sustiel·David G. Grier
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Abstract

We present a novel immersed boundary method that implements acoustic perturbation theory to model an acoustically levitated droplet. Instead of resolving sound waves numerically, our hybrid method solves acoustic scattering semi-analytically and models the corresponding time-averaged acoustic forces on the droplet. This framework allows the droplet to be simulated on inertial timescales of interest, and thereby admit a much larger time resolution than traditional compressible flow solvers. To benchmark this technique and demonstrate its utility, we implement the hybrid IBM for a single droplet in a standing wave. Simulated droplet shape deformations and streaming profile agree with theoretical predictions. Our simulations also yield new insights on the streaming profiles for elliptical droplets, for which a comprehensive analytic solution does not exist.

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Jacqueline B. Sustiel, David G. Grier. 2024-03-20. Complex Dynamics of an Acoustically Levitated Fluid Droplet Captured by a Low-Order Immersed Boundary Method. https://arxiv.org/abs/2403.13943

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