Brownian transport in corrugated channels with inertia

TL;DR

This study numerically investigates how inertia affects Brownian particle transport in corrugated channels, revealing that inertial effects are significant in narrow channels and depend on channel shape and fluid viscosity.

Contribution

It demonstrates the importance of inertia in Brownian transport within narrow, corrugated channels, highlighting differences based on channel shape and fluid damping.

Findings

Inertial effects are significant when channel bottlenecks are smaller than a certain diffusion length.

Transport sensitivity to fluid viscosity increases in narrow channels due to inertia.

Inertia corrections differ between smooth and sharp channel corrugations.

Abstract

The transport of suspended Brownian particles dc-driven along corrugated narrow channels is numerically investigated in the regime of finite damping. We show that inertial corrections cannot be neglected as long as the width of the channel bottlenecks is smaller than an appropriate particle diffusion length, which depends on the the channel corrugation and the drive intensity. Being such a diffusion length inversely proportional to the damping constant, transport through sufficiently narrow obstructions turns out to be always sensitive to the viscosity of the suspension fluid. The inertia corrections to the transport quantifiers, mobility and diffusivity, markedly differ for smoothly and sharply corrugated channels.