Related Experiment Video
Updated: Jun 18, 2025
08:19
Induction of Microstreaming by Nonspherical Bubble Oscillations in an Acoustic Levitation System
Published on: May 9, 2021
2.1K
How viscous bubbles collapse: Topological and symmetry-breaking instabilities in curvature-driven hydrodynamics
Benny Davidovitch1, Avraham Klein2
1Physics Department, University of Massachusetts, Amherst, Amherst, MA 01003.
Summary
Sudden changes in liquid bubble pressure cause nonlinear surface dynamics, leading to unique flow patterns and radial wrinkles. This research uncovers new physics in viscous fluid behavior under rapid depressurization.
Area of Science:
- Fluid dynamics
- Nonlinear surface dynamics
- Viscous liquid behavior
Background:
- The established duality between elastic deformations and noninertial viscous flows is broken under rapid changes in liquid film equilibrium.
- Geometrically nonlinear surface dynamics in doubly curved liquid films, particularly during sudden depressurization, remain largely unexplored.
Purpose of the Study:
- To investigate the unexplored noninertial yet geometrically nonlinear surface dynamics of liquid films forced out of mechanical equilibrium.
- To identify the driving mechanisms behind these dynamics, focusing on temporal variations in surface curvature.
- To analyze the specific case of a floating bubble undergoing rapid depressurization.
Main Methods:
- Theoretical analysis of a floating bubble undergoing rapid depressurization.
- Investigation of topological instabilities and front propagation in evolving bubble surfaces.
- Examination of singular flow structures analogous to disclinations in elastic systems.
- Analysis of symmetry-breaking instabilities leading to radial wrinkle formation.
Main Results:
- Temporal variations in surface curvature drive nonlinear dynamics in viscous liquid films.
- A spontaneous nucleation and expansion of a planar zone with a singular flow structure occurs.
- Hoop compression triggers symmetry-breaking instabilities, resulting in radial wrinkles on the flattening bubble surface.
- The observed dynamics are characterized as a nonequilibrium branch of "jellium" physics, with rate-of-change of curvature analogous to charge.
Conclusions:
- The study reveals a novel class of surface dynamics in viscous films driven by changing curvature, distinct from traditional elastic-viscous analogies.
- The formation of radial wrinkles is explained through a symmetry-breaking instability triggered by hoop compression.
- A discrepancy between linear stability analysis predictions and experimental observations of wrinkle wavelength is highlighted, suggesting the need for advanced theoretical frameworks.
More Related Videos
Related Concept Videos
01:13Excess Pressure Inside a Drop and a Bubble
1.6K
The shape of a small drop of liquid can be considered spherical, neglecting the effect of gravity. This drop can further be considered as two equal hemispherical drops put together due to surface tension. The forces acting on the spherical drop are due to the pressure of the liquid inside the drop, the pressure due to air outside the drop, and the force due to the surface tension acting on the two hemispherical drops.
1.6K
01:28Irrotational Flow
437
Irrotational flow is characterized by fluid motion where particles do not rotate around their axes, resulting in zero vorticity. For a flow to be irrotational, the curl of the velocity field must be zero. This imposes specific conditions on velocity gradients. For instance, to maintain zero rotation about the z-axis, the gradient condition:
437
01:04Hydrostatic Pressure Force on a Curved Surface
1.8K
Hydrostatic pressure on curved surfaces is a fundamental concept in fluid mechanics with broad applications in the civil engineering field. When fluid is in contact with a curved surface, as in a reservoir, dam, or storage tank, it exerts pressure that varies in magnitude and direction along the curved surface. To assess the total hydrostatic force exerted by the fluid on a curved structure, engineers typically isolate the fluid volume adjacent to the surface and analyze the forces acting on...
1.8K
01:19Viscosity of Fluid
376
Viscosity measures the resistance a fluid offers to flow and deformation. It results from internal friction between layers of fluid moving relative to one another. Dynamic viscosity, denoted by the Greek letter mu (μ), quantifies the force needed to move one fluid layer over another. For Newtonian fluids like water and air, the relationship between the shearing stress and the rate of shearing strain is linear, meaning their viscosity remains constant regardless of the applied stress.
376
01:28Euler's Equations of Motion
438
In fluid mechanics, shear stresses arise from viscosity, which represents a fluid's internal resistance to deformation. For low-viscosity fluids, like water, these stresses are minimal, simplifying flow analysis by allowing the fluid to be treated as inviscid, or frictionless. In an inviscid fluid, shear stresses are absent, leaving only normal stresses, which act perpendicularly to fluid elements. Notably, pressure — defined as the negative of the normal stress — remains...
438
01:28Navier–Stokes Equations
462
For incompressible Newtonian fluids, where density remains constant, stresses show a linear relationship with the deformation rate, defined by normal and shear stresses. Normal stresses depend on the pressure exerted on the fluid and the rate of deformation in specific directions, which determines how fluid flows under varying pressures. Shear stresses, on the other hand, act tangentially across fluid layers. They explain how adjacent fluid layers slide relative to one another, connecting...
462