A Novel Apparatus For Particle-Particle Single Contact Electrification Experiments

TL;DR

This paper introduces a novel apparatus combining pneumatic conveying and acoustic levitation to enable high-speed, isolated particle collisions for studying triboelectrification, providing high success rates and detailed insights into charge transfer mechanisms.

Contribution

The paper presents a new apparatus that allows controlled, high-speed, isolated collisions between particles, improving experimental capabilities for triboelectrification studies.

Findings

Charge transfer is stochastic and not solely driven by contact potential difference.

The apparatus achieves a 93% collision success rate.

Large datasets are needed to understand charge transfer processes.

Abstract

The experiment of a single contact between two sub-centimeter high-speed particles is often difficult to execute, especially if the collision must be physically and electrically isolated, as is the case for triboelectrification studies. Apparatuses designed for this type of experiment fall short of providing high-speed isolated collisions with a high probability of contact. In this article, we propose a novel apparatus that combines pneumatic conveying and acoustic levitation to provide an electrically and physically isolated, high impact speed collision between two sub-centimeter particles with a collision success rate of 93 %. We can control the pre-contact charge, material, and size of both particles, and the impact speed and angle. Test results show that charge transfer between two insulator particles is not solely driven by contact potential difference; it is a stochastic process that requires large datasets to resolve and understand. Our new apparatus can efficiently generate these datasets and provide new insights on the stochastic nature of charge transfer, and the effect of each of the collision parameters mentioned earlier on particle-particle charge transfer.