Giant negative mobility of inertial particles caused by the periodic potential in steady laminar flows

TL;DR

This study demonstrates that inertial particles in steady laminar flows can exhibit giant negative mobility due to periodic potentials, with potential for enhanced control of particle transport.

Contribution

It reveals how periodic potentials can induce and amplify negative and positive mobility in inertial particles within laminar flows, a novel insight into particle transport control.

Findings

Giant negative mobility can be achieved with suitable periodic potentials.

Periodic potential profiles significantly influence nonlinear mobility responses.

Both negative and positive giant mobilities are observed under specific conditions.

Abstract

Transport of an inertial particle advected by a two-dimensional steady laminar flow is numerically investigated in the presences of a constant force and a periodic potential. Within particular parameter regimes this system exhibits absolute negative mobility, which means that the particle can travel in a direction opposite to the constant force. It is found that the profile of the periodic potential plays an important role in the nonlinear response regime. Absolute negative mobility can be drastically enhanced by applying appropriate periodic potential, the parameter regime for this phenomenon becomes larger and the amplitude of negative mobility grows exceedingly large (giant negative mobility). In addition, giant positive mobility is also observed in the presence of appropriate periodic potential.