Mean Discharge Time Drops Non-Linearly With Reynolds Number in Gliding Arc CO2 Reactors

Researchers at the submitting institution recorded high-speed video synchronized with electrical traces to classify distinct gliding arc modes. They extracted mean discharge time distributions across a range of flow rates, demonstrating that the metric tracks the transition from stable elongated arcs to frequent re-ignition events. This operando descriptor reveals fluid-dynamic influences previously omitted from reactor performance reports.

The non-linear dependence implies an optimal Reynolds window where arc lifetime remains long enough for efficient vibrational excitation of CO2 yet short enough to avoid thermalization losses. Prior literature on gliding arcs emphasized power and gas composition while treating flow as a secondary parameter; the new data indicate that flow-induced changes in discharge time can shift energy efficiency by amounts comparable to catalyst effects reported in earlier studies.

Integration with recent plasma-catalysis work suggests hybrid reactors could exploit controlled turbulence to maintain the identified discharge-time regime. Scalability assessments will require testing whether the same Reynolds scaling holds at higher powers and larger electrode gaps typical of industrial modules.

Next steps include closed-loop flow control using real-time discharge-time feedback and direct comparison against dielectric-barrier and microwave CO2 reactors under matched energy-input conditions.