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arXiv · 1610.02100

Dynamics of suspended rigid aggregating particles in flowing medium: theory, analysis and scientific computing

Sarthok Sircar·Anthony J. Roberts
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Abstract

We develop and present a unified multi-scale model (involving three scales of spatial organisation) to study the dynamics of rigid aggregating particles suspended in a viscous fluid medium and subject to a steady poiseuille flow. At micro-level, the theory of adhesion describing the attachment / detachment kinetics of two rigid spheres coated with binding ligands, is utilized to describe the collision frequency function. The meso-scale dynamics is outlined through a continuous general dynamic equation governing the time rate of change of the particle size distribution function. The micro-meso coupling is achieved via the balancing of the mesoscale drag forces and couples with the micro-scale forces associated with the binder kinetics. Inside the macro domain (i.e., a long pipe), the model is equation free and divided into equal sized patches. The macroscale solution within each patch is obtained via appropriate (extrapolatory) coupling and amplitude conditions.

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Sarthok Sircar, Anthony J. Roberts. 2016-10-06. Dynamics of suspended rigid aggregating particles in flowing medium: theory, analysis and scientific computing. https://arxiv.org/abs/1610.02100

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