New Model Predicts Nonspherical Gas Bubble Dynamics in Viscoelastic Materials
Researchers have developed a new mathematical model that more accurately predicts how gas bubbles deform and oscillate in viscoelastic soft materials by incorporating a rotational degree of freedom. Existing models failed to adequately capture the nonspherical rotational dynamics of such bubbles, which affect stress transmission and energy dissipation in surrounding tissue-like materials. The advance has implications for biomedical applications such as ultrasound therapy and high-strain-rate rheological measurements.
A new theoretical model for nonspherical gas bubble dynamics in viscoelastic soft materials has been posted to arXiv by Sawyer Remillard and collaborators. The model addresses a gap in prior work by superposing a rotational contribution onto the standard potential-based perturbation framework, alongside linearized forward and inverse coordinate maps used to compute velocities, accelerations, and stresses. The surrounding material is described using a Kelvin-Voigt constitutive model incorporating Newtonian viscosity and quadratic strain-stiffening neo-Hookean elasticity. A key finding is that when elastic effects dominate over viscous ones, shear waves radiate outward from the bubble surface, delocalizing strain energy and increasing damping of perturbation amplitudes compared to purely potential-based models. The model recovers established results for viscous fluids when elasticity is neglected and oscillations are small, and it shows agreement with both ultrasound-forced experiments on shape mode stability and laser-induced cavitation data on temporal shape mode evolution.
What's missing
As a preprint, this work has not yet undergone formal peer review. The model's validation relies on comparisons with a limited set of prior experimental datasets; broader experimental validation across different material types, bubble sizes, and forcing conditions remains to be demonstrated. The study's own scope is limited to the Kelvin-Voigt constitutive framework, and the authors do not address how the model performs for more complex viscoelastic constitutive laws (e.g., Maxwell or Oldroyd-B models) that may better represent certain biological tissues.
What different sources said
- arXiv physicsCenter
Nonspherical gas bubble dynamics in viscoelastic soft materials
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