Three‐Dimensional Fluid Dynamics Simulation of Cross‐Scale Multi‐Needle Corona Discharges

ABSTRACT Studying cross‐scale multi‐source corona discharges is crucial for plasma applications, yet current 2D models cannot capture complex 3D spatial shielding. To address this, we developed and experimentally validated a 3D fluid dynamics model for a cross‐scale needle‐to‐plate discharge (the curvature radius of the needle electrode is 0.2 mm, the vertical gap between the needle tip and the plate is 225 mm) with a maximum normalized current error of 10%. We found that increasing electrode count boosts total current but diminishes average single‐needle current due to intensified electrostatic shielding and edge effects. Crucially, spatial topology dictates discharge efficacy: a “linear” configuration minimizes spatial coupling, consistently outperforming denser arrays. This interference weakens at elevated voltages or larger gaps. These findings elucidate 3D spatial coupling dynamics, guiding the optimization of multi‐electrode layouts.