Viscous streaming in the vicinity of three-dimensional elastic structures

Viscous streaming, also termed steady streaming or classically acoustic streaming, is a secondary inertial effect that arises when viscous fluids oscillate around an immersed object. It is an efficient rectification mechanism that exploits the steady flow emerging out of the oscillatory base flow and has found extensive applications in microfluidics and particle manipulation. Classical investigations focus on the structure of streaming flows in the vicinity of rigid bodies, leading to a robust theoretical framework based primarily on asymptotic approximations. Recent studies, motivated by its biological implications, have ventured beyond rigid body streaming and theoretically elucidated the impact of body elasticity on streaming flows in two dimensions. In this study, we generalize those findings to three dimensions, via a minimal case study of an immersed soft sphere. We first consider the streaming solution in the rigid sphere limit, where we improve upon an existing solution by considering previously unaccounted terms. We then enable body compliance, exposing a three-dimensional, elastic streaming process available even in Stokes flows. Such effect, consistent with two-dimensional analyses but analytically distinct, is validated against direct numerical simulations and shown to translate to bodies of complex three-dimensional geometry and topology, paving the way for advanced forms of flow control.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Mechanical Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2024

Author dc:creator

• Cui, Songyuan

Contributors dc:contributor

• Gazzola, Mattia

• Fluid-structure Interactions
• Soft-body Dynamics
• Viscous Streaming

Statement dc:rights

• Copyright 2024 Songyuan Cui

Language dc:language

en, eng

Handle dc:identifier

https://hdl.handle.net/2142/125521

OAI record oai:identifier

https://www.ideals.illinois.edu/oai-pmh?verb=GetRecord&metadataPrefix=etdms&identifier=oai%3Awww.ideals.illinois.edu%3A2142%2F125521