Particle flows in a dc discharge in laboratory and microgravity conditions

TL;DR

This study compares dust particle flows in a dc discharge under laboratory and microgravity conditions, revealing higher velocities in laboratory settings explained by a physical interaction model that aligns well with experimental data.

Contribution

It introduces a physical model explaining particle flow differences in laboratory and microgravity conditions, validated by experimental and theoretical velocity comparisons.

Findings

Particle flow velocities are higher in laboratory than in microgravity.

The proposed model accurately predicts particle velocities across conditions.

Reasonable agreement between measured and calculated velocities was achieved.

Abstract

We describe a series of experiments on dust particles flows in a positive column of a horizontal dc discharge operating in laboratory and microgravity conditions. The main observation is that the particle flow velocities in laboratory experiments are systematically higher than in microgravity experiments, for otherwise identical discharge conditions. The paper provides an explanation for this interesting and unexpected observation. The explanation is based on a physical model, which properly takes into account main plasma-particle interaction mechanisms relevant to the described experimental study. Comparison of experimentally measured particle velocities and those calculated using the proposed model demonstrates reasonable agreement, both in laboratory and microgravity conditions, in the entire range of discharge parameters investigated.