eprintid: 10180127 rev_number: 14 eprint_status: archive userid: 699 dir: disk0/10/18/01/27 datestamp: 2023-11-03 16:55:20 lastmod: 2024-04-15 14:06:50 status_changed: 2023-11-03 16:55:20 type: article metadata_visibility: show sword_depositor: 699 creators_name: Dalwadi, Mohit creators_name: Moreau, Clément creators_name: Gaffney, Eamonn creators_name: Ishimoto, Kenta creators_name: Walker, Benjamin title: Generalised Jeffery’s equations for rapidly spinning particles. Part 1: Spheroids ispublished: pub divisions: UCL divisions: B04 divisions: C06 divisions: F59 note: © The Author(s), 2024. Published by Cambridge University Press. This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/licenses/by/4.0). abstract: The observed behaviour of passive objects in simple flows can be surprisingly intricate, and is complicated further by object activity. Inspired by the motility of bacterial swimmers, in this two-part study we examine the three-dimensional motion of rigid active particles in shear Stokes flow, focusing on bodies that induce rapid rotation as part of their activity. In Part 1 we develop a multiscale framework to investigate these emergent dynamics and apply it to simple spheroidal objects. In Part 2 (Dalwadi et al., J. Fluid Mech., vol. 979, 2024, A2) we apply our framework to understand the emergent dynamics of more complex shapes; helicoidal objects with chirality. Via a multiple scales asymptotic analysis for nonlinear systems, we systematically derive emergent equations of motion for long-term trajectories that explicitly account for the strong (leading-order) effects of fast spinning. Supported by numerical examples, we constructively link these effective dynamics to the well-known Jeffery's orbits for passive spheroids, deriving an explicit closed-form expression for the effective shape of the active particle, broadening the scope of Jeffery's seminal study to spinning spheroids. date: 2024-01-25 date_type: published publisher: Cambridge University Press official_url: https://doi.org/10.1017/jfm.2023.923 oa_status: green full_text_type: pub language: eng primo: open primo_central: open_green verified: verified_manual elements_id: 2103499 doi: 10.1017/jfm.2023.923 lyricists_name: Dalwadi, Mohit lyricists_id: MDALW30 actors_name: Allington-Smith, Dominic actors_id: DAALL44 actors_role: owner full_text_status: public publication: Journal of Fluid Mechanics volume: 979 article_number: A1 citation: Dalwadi, Mohit; Moreau, Clément; Gaffney, Eamonn; Ishimoto, Kenta; Walker, Benjamin; (2024) Generalised Jeffery’s equations for rapidly spinning particles. Part 1: Spheroids. Journal of Fluid Mechanics , 979 , Article A1. 10.1017/jfm.2023.923 <https://doi.org/10.1017/jfm.2023.923>. Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/10180127/13/Dalwadi_Generalised%20Jeffery%27s%20equations%20for%20rapidly%20spinning%20particles_VoR2.pdf