We present a new method for sampling stochastic displacements in Brownian Dynamics
(BD) simulations of colloidal scale particles. The method relies on a new formulation for
Ewald summation of the Rotne-Prager-Yamakawa (RPY) tensor, which guarantees that the
real-space and wave-space contributions to the tensor are independently symmetric and
positive-definite for all possible particle configurations. Brownian displacements are drawn
from a superposition of two independent samples: a wave-space (far-field or long-ranged) …

Brownian Dynamics simulations are an important tool for modeling the dynamics of soft
matter. However, accurate and rapid computations of the hydrodynamic interactions
between suspended, microscopic components in a soft material are a significant
computational challenge. Here, we present a new method for Brownian dynamics
simulations of suspended colloidal scale particles such as colloids, polymers, surfactants,
and proteins subject to a particular and important class of hydrodynamic constraints. The …