English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT

Released

Journal Article

Flutter to tumble transition of buoyant spheres triggered by rotational inertia changes

MPS-Authors
/persons/resource/persons192998

Lohse,  Detlef
Max Planck Institute for Dynamics and Self-Organization, Max Planck Society;

External Resource
No external resources are shared
Fulltext (restricted access)
There are currently no full texts shared for your IP range.
Fulltext (public)
There are no public fulltexts stored in PuRe
Supplementary Material (public)
There is no public supplementary material available
Citation

Mathai, V., Zhu, X., Sun, C., & Lohse, D. (2018). Flutter to tumble transition of buoyant spheres triggered by rotational inertia changes. Nature Communications, 9: 1792. doi:10.1038/s41467-018-04177-w.


Cite as: https://hdl.handle.net/21.11116/0000-0001-44FA-9
Abstract
Heavy particles sink straight in water, while buoyant bubbles and spheres may zigzag or spiral as they rise. The precise conditions that trigger such path-instabilities are still not completely understood. For a buoyant rising sphere, two parameters are believed to govern the development of unsteady dynamics: the particle's density relative to the fluid, and its Galileo number. Consequently, with these parameters specified, the opportunities for variation in particle dynamics appear limited. In contrast to this picture, here we demonstrate that vigorous path-oscillations can be triggered by modulating a spherical particle's moment of inertia (MoI). For a buoyant sphere rising in a turbulent flow, MoI reduction triggers a tumble-flutter transition, while in quiescent liquid, it induces a modification of the sphere wake resulting in large-amplitude path-oscillations. The present finding opens the door for control of particle path- and wake-instabilities, with potential for enhanced mixing and heat transfer in particle-laden and dispersed multiphase environments.