Title: Self-propelled soft-core dumbbells for the simulation of active suspensions --- application to self-motile bacterial suspensions

Presenter: Denis F. Hinz

Authors: Denis F. Hinz, Alexander Panchenko, Tae-Yeon Kim, and Eliot Fried

Affiliation: McGill University

Abstract: A simple model for simulating flows of active suspensions is presented. The approach is based on the dissipative particle dynamics framework. While the model is potentially applicable to a wide range of self-propelled particle systems, the specific class of self-motile bacterial suspensions is considered as a modeling scenario. To mimic the rod-like geometry of a bacterium, two dissipative particle dynamics particles are connected by a stiff harmonic spring to form an aggregate dissipative particle dynamics molecule. The bacterial motility is modeled through a constant self-propulsion force applied along the rod axis of each such aggregate molecule. Numerical simulations of this system are performed using a customized version of the open-source LAMMPS (Large-scale Atomic/Molecular Massively Parallel Simulator) software package. Detailed studies of the influence of particle concentration, pairwise dissipative interaction forces, and Stokes drag forces on the statistics of the system are provided.