Ph.D. Thesis Proposal

Zoelle Wong

(Faculty advisor: Professor Juergen Rauleder)

"Magnetohydrodynamic Effects in Supercritical Carbon Dioxide for Arc Quenching Applications"

Monday, August 17

2:00 - 4:00 p.m.

Montgomery Knight Bldg. 317

Abstract: 

With the increasing demand for electrification and the reduction of greenhouse gas emissions, supercritical carbon dioxide (scCO₂) has emerged as a promising medium for a variety of plasma applications spanning atmospheric to ultra-high-pressure conditions. However, under the combined influence of extreme temperatures and pressures, experimental diagnostics and flow visualization of electrical arcs become severely limited or inaccessible, necessitating computational models to resolve otherwise unobservable phenomena. The fidelity of these models, however, depends on experimental validation, and assumptions developed for thermal arcs at ambient pressures may not remain valid under such elevated thermodynamic conditions. This limitation motivates a systematic re-evaluation of the modeling assumptions and constraints governing this class of arc-flow problems.

This study introduces a magnetohydrodynamic framework coupled with an arc-surrogate model for the investigation of electrical arcs at ultra-high pressures and temperatures. The proposed framework is applied to model the internal flow within a sulfur hexafluoride (SF₆)-free high-voltage switchgear, developed as part of this research, a system characterized by highly pressurized arcs (up to 100 bar) and temperatures exceeding 20,000 K. Using this framework, the study will assess the influence of nozzle geometry on heat transfer, examines the effects of contact separation on flow dynamics, and performs model verification through dimensional analysis.

Committee:

Dr. Juergen Rauleder (advisor), School of Aerospace Engineering
Dr. Lukas Graber, School of Electrical and Computer Engineering
Dr. Joseph Oefelein, School of Aerospace Engineering
Dr. Sedina Tsikata, School of Aerospace Engineering