Synchronising and Non-synchronising Dynamics for a Two-species Aggregation Model

Casimir Emako; Jie Liao; Nicolas Vauchelet

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arXiv · 1505.07659

Synchronising and Non-synchronising Dynamics for a Two-species Aggregation Model

Casimir Emako·Jie Liao·Nicolas Vauchelet

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Abstract

This paper deals with analysis and numerical simulations of a one-dimensional two-species hyperbolic aggregation model. This model is formed by a system of transport equations with nonlocal velocities, which describes the aggregate dynamics of a two-species population in interaction appearing for instance in bacterial chemotaxis. Blow-up of classical solutions occurs in finite time. This raises the question to define measure-valued solutions for this system. To this aim, we use the duality method developed for transport equations with discontinuous velocity to prove the existence and uniqueness of measure-valued solutions. The proof relies on a stability result. In addition, this approach allows to study the hyperbolic limit of a kinetic chemotaxis model. Moreover, we propose a finite volume numerical scheme whose convergence towards measure-valued solutions is proved. It allows for numerical simulations capturing the behaviour after blow up. Finally, numerical simulations illustrate the complex dynamics of aggregates until the formation of a single aggregate: after blow-up of classical solutions, aggregates of different species are synchronising or nonsynchronising when collide, that is move together or separately, depending on the parameters of the model and masses of species involved.

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Casimir Emako, Jie Liao, Nicolas Vauchelet. 2015-05-28. Synchronising and Non-synchronising Dynamics for a Two-species Aggregation Model. https://arxiv.org/abs/1505.07659

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