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arXiv · 2011.11161

Poisson-bracket formulation of the dynamics of fluids of deformable particles

Arthur Hernandez·M. Cristina Marchetti
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Abstract

Using the Poisson bracket method, we derive continuum equations for a fluid of deformable particles in two dimensions. Particle shape is quantified in terms of two continuum fields: an anisotropy density field that captures the deformations of individual particles from regular shapes and a shape tensor density field that quantifies both particle elongation and nematic alignment of elongated shapes. We explicitly consider the example of a dense biological tissue as described by the Vertex model energy, where cell shape has been proposed as a structural order parameter for a liquid-solid transition. The hydrodynamic model of biological tissue proposed here captures the coupling of cell shape to flow, and provides a starting point for modeling the rheology of dense tissue.

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Arthur Hernandez, M. Cristina Marchetti. 2020-11-23. Poisson-bracket formulation of the dynamics of fluids of deformable particles. https://doi.org/10.1103/physreve.103.032612

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