Related Experiment Video
Updated: Aug 17, 2025

Preparation and 3D Tracking of Catalytic Swimming Devices
Published on: July 1, 2016
Collective behavior of passive and active circle swimming particle mixtures
Bhadra Hrishikesh1, Ethayaraja Mani1
1Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai, 600 036, Tamil Nadu, India. ethaya@iitm.ac.in.
Abstract:
We present a numerical study on a binary mixture of passive and circle swimming, self-propelling particles which interact via the Lennard-Jones (LJ) potential in two dimensions. Using Brownian Dynamics (BD) simulations, we present state diagrams using the control parameters such as attraction strength, angular velocity, self-propulsion velocity and composition. In a symmetric mixture, the system undergoes a transition from a mixed gel to a rotating passive cluster state and finally to a homogeneous fluid state as translational activity increases. The formation of the rotating cluster of passive particles surrounded by active and passive monomers is attributed to the combined effect of composition, activity and strength of attraction of the active particles. Different phases are characterized using radial distribution functions, bond order parameters, cluster fraction and probability distribution of local volume fractions. The present study addresses comprehensively the intricate role of activity, angular velocity, inter-particle interaction and compositional variation on the phase behavior. The predictions presented in the study can be experimentally realized in synthetic colloidal swimmers and motile bacterial suspensions.
Related Concept Videos
Colloids and Suspensions
Buoyancy and Stability for Submerged and Floating Bodies
Newtonian Fluid: Problem Solving
A velocity gradient forms within the fluid when a Newtonian fluid is placed between two parallel plates, with...
Passive Diffusion: Overview and Kinetics
When administered orally, drugs establish a substantial concentration gradient between the gastrointestinal (GI) lumen and the bloodstream, expediting...
Coagulation
Hydrostatic Pressure Force on a Curved Surface

