Immersed Boundary Simulations of Active Fluid Droplets

Abstract

We present numerical simulations of active fluid droplets immersed in an external fluid in 2-dimensions { using} an Immersed Boundary method to simulate the fluid droplet interface as a Lagrangian mesh. We present results from two example systems, firstly an active isotropic fluid boundary consisting of particles that can bind and unbind from the interface and generate surface tension gradients through active contractility. Secondly, a droplet filled with an active polar fluid with { homeotropic} anchoring at the droplet interface. These two systems demonstrate spontaneous symmetry breaking and steady state dynamics resembling cell motility and division and show complex feedback mechanisms with minimal degrees of freedom. The simulations outlined here will be useful for quantifying the wide range of dynamics observable in these active systems and modelling the effects of confinement in a consistent and adaptable way.

27 pages, 11 figures, 3 tables

References in corpus (6)

• Spontaneous motion in hierarchically assembled active matter
• Topology and Dynamics of Active Nematic Vesicles
• A minimal physical model captures the shapes of crawling cells
• Filling an emulsion drop with motile bacteria
• Motility of active fluid drops on surfaces
• Instabilities, motion and deformation of active fluid droplets

Cited by in corpus (5)

• Contractile and chiral activities co-determine the helicity of swimming droplet trajectories
• Vesicle shape transformations driven by confined active filaments
• Instabilities, motion and deformation of active fluid droplets
• Kinematic and dynamic forcing strategies for predicting the transport of inertial capsules via a combined lattice Boltzmann-Immersed Boundary method
• Computational modeling of active deformable membranes embedded in 3D flows