Helical Plasma Plumes in Pulsed RF Jets Show Enhanced Target Interaction Area
Researchers experimentally demonstrated that helical plasma plumes generated by pulsed radiofrequency atmospheric plasma jets interact with target surfaces over a significantly larger area than conventional conical plumes from continuous RF excitation. The helical morphology arises from Kelvin-Helmholtz instabilities and baroclinic torque, creating a rotating trajectory that improves air entrainment and reactive species distribution. These findings suggest helical plasma jets could be more effective for applications like plasma medicine, surface modification, and plasma-liquid interactions.
A new study published on arXiv investigates how helical plasma plumes—generated through pulsed radiofrequency excitation at atmospheric pressure—interact with target surfaces. Using high-speed imaging, researchers compared helical plumes with conventional conical plumes produced under continuous RF excitation and found that the helical configuration significantly enlarges the effective plasma-target interaction region. The helical plume's rotating trajectory and enhanced air entrainment lead to superior surface coverage, improved spatial distribution of reactive species, and enhanced plasma-surface coupling. The team systematically examined interactions with different target materials and boundary conditions, including dielectric surfaces and metal-backed substrates. These results suggest that helical plasma jets offer advantages for large-area plasma treatment applications in medicine, materials science, and other fields.
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- arXiv physicsCenter
Enhanced Target Interaction Area of Helical Plasma Plumes in a Pulsed RF Atmospheric Plasma Jet
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