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arXiv · 2403.13917

Evidence of Chaotic Mixing in the Alveolar Region of the Lung

Prabhash Kumar·Prahallada Jutur·Anubhab Roy·Mahesh Panchagnula
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Abstract

We report an experimental and numerical investigation to study the role of asymmetry in the expansion-contraction of the acinar wall on the particle transport in the acinus. We model the acinar flow feature using a T-section by appropriately matching the dimensionless numbers to that in the acinus of healthy human subjects. We show that asymmetry in the expansion-contraction process (quantified by $\phi$) is required for chaotic advection. We show the stretch and fold process leading to chaos for a range of $\phi$ and scaled oscillation frequency $Sr$. We show a regime map in this generalize $\phi$ and $Sr$ space and show that most mammalian lungs fall at the boundary of chaotic regime.

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Prabhash Kumar, Prahallada Jutur, Anubhab Roy, Mahesh Panchagnula. 2024-03-20. Evidence of Chaotic Mixing in the Alveolar Region of the Lung. https://arxiv.org/abs/2403.13917

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