Characterizing the Movement of Contaminant Liquid Metal Particles when subject to Electric Pulses, within the Context of Z-pinch Fusion Reactors

Abstract

This thesis examines the behavior of contaminant liquid metal particles, known as ejecta, which are expelled from magnetically-accelerated liquid metal surfaces, in Z-pinch fusion reactors. These ejecta present significant contamination risks to plasma fuel in fusion reactors. The study employed a liquid electrode setup, exposing a eutectic tin-bismuth mixture to high-current pulses. Particle motion was tracked and analyzed using high-speed camera footage processed with advanced techniques, including contrast limited adaptive histogram equalization (CLAHE), neutral-density filtering, and Sobel edge detection. The research integrates automated particle tracking algorithms with connected-component labeling and two-point correlation functions to monitor ejecta trajectories. Results reveal an average ejected particle velocity of 2.54 m/s (±3.58 m/s), with particle formation likelihood peaking at velocities around 1.14 m/s. These findings indicate that particle ejection dynamics are influenced by factors such as initial temperature, vacuum conditions, and electrostatic forces. This research provides crucial insights for optimizing reactor design and mitigating contamination in future fusion energy applications. The study also proposes directions for further investigation, including the temperature dependency of particle ejection dynamics and the implementation of improved heating systems for experimental setups.