The effect of dust charge variation, due to ion flow and electron depletion, on dust levitation

TL;DR

This paper investigates how dust charge variations caused by ion flow and electron depletion affect dust levitation in plasma discharges, using a fluid model and force balance analysis.

Contribution

It introduces a detailed analysis of dust charge variation effects on dust levitation height considering ion flow and electron depletion.

Findings

Dust charge variation significantly influences levitation height.

Ion flow and electron depletion alter plasma densities and electron temperature.

Force balance approach effectively predicts dust levitation in different plasma conditions.

Abstract

Using a fluid model, the plasma densities, electron temperature and ion Mach number in front of a powered electrode in different plasma discharges is computed. The dust charge is computed using OML theory for Maxwellian electrons and ions distributed according to a shifted-Maxwellian. By assuming force balance between gravity and the electrostatic force, the dust levitation height is obtained. The importance of the dust charge variation is investigated.