Super-fast bullet bubbles transported in a pressure-driven cylindrical flow

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteurs principaux: Cappello, Jean, Rivero-Rodriguez, Javier, Scheid, Benoit
Format: Preprint
Publié: 2025
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866917884777725952
author Cappello, Jean
Rivero-Rodriguez, Javier
Scheid, Benoit
author_facet Cappello, Jean
Rivero-Rodriguez, Javier
Scheid, Benoit
contents When transported by a pressure driven flow in a cylindrical pipe, bubbles may exhibit very fast velocities. In this paper, we show that, when the bubbles are largely deformable, that is, at large capillary numbers Ca, the velocity of the bubble can be larger than the maximal velocity of the flow that transports them. We call this regime "super-fast". However, the situation changes when inertia comes at play for increasing Reynolds numbers Re, and the relative velocity of the bubble drops for sufficiently large Laplace number, defined as La = Re/Ca. In this article, we uncover the conditions for which the super-fast regime exists : the deformability of the drop is crucial, and hence the capillary number needs to be larger than a critical value, yet smaller than a threshold above which the bubble breaks up. The two limiting capillary numbers are presented in a phase diagram as a function of the bubble size and the Laplace number.
format Preprint
id arxiv_https___arxiv_org_abs_2501_02993
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Super-fast bullet bubbles transported in a pressure-driven cylindrical flow
Cappello, Jean
Rivero-Rodriguez, Javier
Scheid, Benoit
Fluid Dynamics
When transported by a pressure driven flow in a cylindrical pipe, bubbles may exhibit very fast velocities. In this paper, we show that, when the bubbles are largely deformable, that is, at large capillary numbers Ca, the velocity of the bubble can be larger than the maximal velocity of the flow that transports them. We call this regime "super-fast". However, the situation changes when inertia comes at play for increasing Reynolds numbers Re, and the relative velocity of the bubble drops for sufficiently large Laplace number, defined as La = Re/Ca. In this article, we uncover the conditions for which the super-fast regime exists : the deformability of the drop is crucial, and hence the capillary number needs to be larger than a critical value, yet smaller than a threshold above which the bubble breaks up. The two limiting capillary numbers are presented in a phase diagram as a function of the bubble size and the Laplace number.
title Super-fast bullet bubbles transported in a pressure-driven cylindrical flow
topic Fluid Dynamics
url https://arxiv.org/abs/2501.02993