On the role of the history force for inertial particles in turbulence

TL;DR

This paper investigates the impact of the often-neglected history force on inertial particles in turbulence, revealing its significant influence on particle dynamics and collision rates across various parameters.

Contribution

It provides a comprehensive analysis of the history force's effects on inertial particles in turbulent flows, highlighting its importance and parameter dependence.

Findings

History force significantly affects slip velocity and acceleration.

It alters preferential concentration and collision rates.

Effects vary with particle parameters.

Abstract

The history force is one of the hydrodynamic forces which act on a particle moving through a fluid. It is an integral over the full time history of the particle's motion and significantly complicates the equations of motion (accordingly it is often neglected). We present here a study of the influence of this force on particles moving in a turbulent flow, for a wide range of particle parameters. It is shown that the magnitude of history force can be significant and that it can have a considerable effect on the particles' slip velocity, acceleration, preferential concentration and collision rate. We also investigate the parameter dependence of the strength of these effects.