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Deformation and stability of a gas bubble in a biaxial straining flow
Phys. Rev. Fluids 11, 064001 – Published 1 June, 2026
DOI: https://doi.org/10.1103/r7bv-xt3l
Abstract
Taking advantage of the recently developed Linearized Arbitrary Lagrangian-Eulerian framework [Sierra-Ausin et al., Phys. Rev. Fluids 7, 113603 (2022)], we characterize the linear dynamics of an incompressible gas bubble immersed in a biaxial straining flow. We show that the system undergoes a saddle-node bifurcation with strongly different equilibrium shapes when varying the Ohnesorge number, , which compares viscous and capillary effects. Equilibrium shapes are found to be oblate for sufficiently large while, counterintuitively, they are prolate for low-enough . The bifurcation diagram is found to contain also two sets of disconnected branches that cannot be obtained by continuation starting from a spherical shape. One set corresponds to bubble shapes expected to be unstable, while the second set comprises a wide region exhibiting stable shapes that might be observed experimentally. We then characterize the linear stability of the various branches. In addition to the unstable axisymmetric mode arising at the saddle-node bifurcation, two nonoscillating drift modes are also identified, together with two unstable modes with azimuthal wave number and two oscillating modes with that appear on oblate bubbles in the presence of large inertial effects. Present results lead to conclusions that may be relevant in the context of bubble breakup in turbulence. In particular, they show that bubbles are much more stable in the biaxial flow geometry than in the uniaxial one. This presumably explains why turbulent breakup mostly happens in uniaxial regions, although biaxial regions are significantly more frequent.
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References (32)
- J. Rodríguez-Rodríguez, J. Gordillo, and C. Martínez-Bazán, Breakup time and morphology of drops and bubbles in a high-Reynolds-number flow, J. Fluid Mech. 548, 69 (2006).
- A. Revuelta, J. Rodríguez-Rodríguez, and C. Martínez-Bazán, Bubble break-up in a straining flow at finite reynolds numbers, J. Fluid Mech. 551, 175 (2006).
- A. Revuelta, J. Rodríguez-Rodríguez, and C. Martínez-Bazán, On the breakup of bubbles at high Reynolds numbers and subcritical Weber numbers, Eur. J. Mech. B Fluids 27, 591 (2008).
- A. U. M. Masuk, A. K. Salibindla, and R. Ni, The orientational dynamics of deformable finite-sized bubbles in turbulence, J. Fluid Mech. 915, A79 (2021).
- C. Meneveau, Lagrangian dynamics and models of the velocity gradient tensor in turbulent flows, Annu. Rev. Fluid Mech. 43, 219 (2011).
- P. L. Johnson and C. Meneveau, Restricted Euler dynamics along trajectories of small inertial particles in turbulence, J. Fluid Mech. 816, R2 (2017).
- A. Naso and A. Pumir, Scale dependence of the coarse-grained velocity derivative tensor structure in turbulence, Phys. Rev. E 72, 056318 (2005).
- I. Kang and L. Leal, Numerical solution of axisymmetric, unsteady free-boundary problems at finite Reynolds number. II. Deformation of a bubble in a biaxial straining flow, Phys. Fluids 1, 644 (1989).
- G. I. Taylor, The formation of emulsions in definable fields of flow, Proc. A 146, 501 (1934).
- G. Gallino, When droplets deform, break up and propel microswimmers, Ph.D. thesis, Ecole Polytechnique Fédérale de Lausanne, Lausanne, 2018.
- A. Acrivos and T. S. Lo, Deformation and breakup of a single slender drop in an extensional flow, J. Fluid Mech. 86, 641 (1978).
- M. J. Miksis, A bubble in an axially symmetric shear flow, Phys. Fluids 24, 1229 (1981).
- G. Ryskin and L. G. Leal, Numerical solution of free-boundary problems in fluid mechanics. Part 3. Bubble deformation in an axisymmetric straining flow, J. Fluid Mech. 148, 37 (1984).
- I. Kang and L. Leal, Numerical solution of axisymmetric, unsteady free-boundary problems at finite Reynolds number. I. Finite-difference scheme and its application to the deformation of a bubble in a uniaxial straining flow, Phys. Fluids 30, 1929 (1987).
- I. S. Kang and L. G. Leal, Small-amplitude perturbations of shape for a nearly spherical bubble in an inviscid straining flow (steady shapes and oscillatory motion), J. Fluid Mech. 187, 231 (1988).
- A. Rivière, L. Duchemin, C. Josserand, and S. Perrard, Bubble breakup reduced to a one-dimensional nonlinear oscillator, Phys. Rev. Fluids 8, 094004 (2023).
- J. Sierra-Ausin, P. Bonnefis, A. Tirri, D. Fabre, and J. Magnaudet, Dynamics of a gas bubble in a straining flow: Deformation, oscillations, self-propulsion, Phys. Rev. Fluids 7, 113603 (2022).
- P. Bonnefis, Etude des instabilités de sillage, de forme et de trajectoire de bulles par une approche de stabilité linéaire globale, Ph.D. thesis, Institut National Polytechnique de Toulouse, 2019.
- P. Bonnefis, J. Sierra-Ausin, D. Fabre, and J. Magnaudet, Path instability of deformable bubbles rising in Newtonian liquids: A linear study, J. Fluid Mech. 980, A19 (2024).
- M. Zabarankin, I. Smagin, O. M. Lavrenteva, and A. Nir, Viscous drop in compressional Stokes flow, J. Fluid Mech. 720, 169 (2013).
- S. Malik, O. M. Lavrenteva, and A. Nir, Shapes and stability of viscous rotating drops in a compressional/extensional flow, Phys. Rev. Fluids 5, 023604 (2020).
- S. Malik, O. M. Lavrenteva, M. Idan, and A. Nir, Stationary dimpled drops under linear flow, J. Fluid Mech. 983, A5 (2024).
- M. Zabarankin, O. M. Lavrenteva, and A. Nir, Liquid toroidal drop in compressional Stokes flow, J. Fluid Mech. 785, 372 (2015).
- B. Ee, O. Lavrenteva, I. Smagin, and A. Nir, Evolution and stationarity of liquid toroidal drop in compressional Stokes flow, J. Fluid Mech. 835, 1 (2018).
- O. Lavrenteva, B. Ee, I. Smagin, and A. Nir, Approximating stationary deformation of flat and toroidal drops in compressional viscous flow using generalized Cassini ovals, J. Fluid Mech. 921, A5 (2021).
- F. Hecht, New development in , J. Numer. Math. 20, 251 (2012).
- FreeFem, https://freefem.org/.
- D. Fabre, V. Citro, D. Ferreira Sabino, P. Bonnefis, J. Sierra, F. Giannetti, and M. Pigou, A practical review on linear and nonlinear global approaches to flow instabilities, Appl. Mech. Rev. 70, 060802 (2018).
- StabFem, https://stabfem.gitlab.io/StabFem/PUBLICATION_CASES/BiaxialStrainBubble_RiviereEtAl/SCRIPT_STRAINEDBUBBLE_biaxial.html.
- G. Gallino, T. M. Schneider, and F. Gallaire, Edge states control droplet breakup in subcritical extensional flows, Phys. Rev. Fluids 3, 073603 (2018).
- L. G. Leal, Laminar Flow and Convective Transport Processes (Butterworth-Heinemann, Oxford, 1992).
- F. Ravelet, C. Colin, and F. Risso, On the dynamics and breakup of a bubble rising in a turbulent flow, Phys. Fluids 23, 103301 (2011).