New Model Predicts Nonspherical Gas Bubble Dynamics in Viscoelastic Materials
Researchers have developed a mathematical model that better predicts how gas bubbles deform and move in viscoelastic soft materials by accounting for rotational dynamics alongside deformation. The model incorporates both elastic and viscous properties of materials, addressing a gap in existing theories that struggle with nonspherical bubble behavior. This advance is important for applications ranging from medical procedures to high-speed material testing, where accurate bubble dynamics predictions are critical.
A new theoretical framework published on arXiv describes nonspherical gas bubble dynamics in viscoelastic materials by combining rotational and deformational contributions to bubble motion. The model uses a Kelvin-Voigt constitutive framework with Newtonian viscosity and neo-Hookean elasticity to represent the surrounding material, and satisfies momentum balance and stress continuity at the bubble surface. The researchers demonstrate that when elastic effects dominate over viscous effects, shear waves radiate from the bubble, increasing energy dissipation and damping compared to potential-based models alone. The model recovers previous results for viscous fluids when elastic effects are neglected and shows agreement with experimental data from ultrasound-forced bubble oscillations and laser-induced cavitation. This work addresses a significant limitation in existing models that fail to capture rotational dynamics accurately, which is essential for biomedical applications and rheological measurements at high strain rates.
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- arXiv physicsCenter
Nonspherical gas bubble dynamics in viscoelastic soft materials
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