Electron dynamics of three distinct discharge modes of a cross-field atmospheric pressure plasma jet

Maximilian Klich; David Alexander Schulenberg; Sebastian Wilczek; Mate Vass; Tim Bolles; Ihor Korolov; Julian Schulze; Thomas Mussenbrock; Ralf Peter Brinkmann

arXiv · 2501.17601

Electron dynamics of three distinct discharge modes of a cross-field atmospheric pressure plasma jet

Maximilian Klich·David Alexander Schulenberg·Sebastian Wilczek·Mate Vass·Tim Bolles·Ihor Korolov·Julian Schulze·Thomas Mussenbrock·Ralf Peter Brinkmann

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Abstract

This paper investigates the electron dynamics in three distinct discharge modes of a cross-field atmospheric pressure plasma jet, the COST-Jet. Thereby, the discharge modes are the non-neutral, the quasi-neutral, and the constricted mode. Using a hybrid Particle-In-Cell/Monte-Carlo Collisions (PIC/MCC) simulation, the study systematically varies the applied voltage and driving frequency to explore the operation modes and their relations. The results reveal that at low input power, the COST-Jet operates in a non-neutral mode, characterized by a discharge close to extinction, analogous to the chaotic mode observed in other plasma devices. As power increases, the jet transitions to a quasi-neutral mode, which aligns with the well-known {\Omega}- and Penning modes, comparable to the bullet mode in parallel-field jets. At the highest power levels, the COST-Jet enters a constricted mode, where the plasma significantly densifies and constricts towards the electrodes along the entire discharge channel. Experimental validation using phase-resolved optical emission spectroscopy (PROES) supports the simulation findings, particularly identifying the constricted mode as a distinct operational regime. These insights into the mode transitions of the COST-Jet under varying operational conditions help optimize plasma applications in various fields.

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Maximilian Klich, David Alexander Schulenberg, Sebastian Wilczek, Mate Vass, Tim Bolles, Ihor Korolov, Julian Schulze, Thomas Mussenbrock, Ralf Peter Brinkmann. 2025-01-29. Electron dynamics of three distinct discharge modes of a cross-field atmospheric pressure plasma jet. https://arxiv.org/abs/2501.17601

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