Title: Guided plasma jets directed onto wet surfaces: angular dependence and control

Abstract

The optimal use of atmospheric pressure plasma jets (APPJs) for treatment of surfaces—inorganic, organic and liquid—depends on being able to control the flow of plasma-generated reactive species onto the surface. The typical APPJ is a rare gas mixture (RGM) flowed through a tube to which voltage is applied, producing an RGM plasma plume that extends into the ambient air. The RGM plasma plume is guided by a surrounding shroud of air due to the higher electric field required for an ionization wave (IW) to propagate into the air. Additionally, the mixing of the ambient air with the RGM plasma plume then determines the production of reactive oxygen and nitrogen species (RONS). The APPJ is usually oriented perpendicular to the surface being treated. However, the angle of the APPJ with respect to the surface may be a method to control the production of reactive species to the surface due to the change in APPJ propagation properties and the resulting gas dynamics. In this paper, we discuss results from computational and experimental investigations addressing two points—propagation of IWs in APPJs with and without a guiding gas shroud as a function of angle of the APPJ with respect to the surface; and themore » use of this angle to control plasma activation of thin water layers. We found that APPJs propagating out of the plasma tube into a same-gas environment lack any of the directional properties of shroud-guided jets, and largely follow electric field lines as the angle of the plasma tube is changed. Guided APPJs propagate coaxially with the tube as the angle is changed, and turn perpendicularly towards the surface only a few mm above the surface. The angle of the APPJ produces different gas dynamic distributions, which enable some degree of control over the content of RONS transferred to thin water layers.« less

Authors:

Parsey, Guy ^[1]; Lietz, Amanda M.  ^[2];

• Search DOE PAGES for author "Lietz, Amanda M."
• Search DOE PAGES for ORCID "0000-0001-6423-5042"

Kushner, Mark J.  ^[3]

• Search DOE PAGES for author "Kushner, Mark J."
• Search DOE PAGES for ORCID "0000-0001-7437-8573"

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+ Show Author Affiliations

1. Univ. of Michigan, Ann Arbor, MI (United States); KLA Corp., Ann Arbor, MI (United States)
2. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
3. Univ. of Michigan, Ann Arbor, MI (United States)

Publication Date:

Mon Nov 09 00:00:00 EST 2020

Research Org.:

Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

Sponsoring Org.:

USDOE National Nuclear Security Administration (NNSA); USDOE Office of Science (SC), Fusion Energy Sciences (FES), National Science Foundation (NSF)

OSTI Identifier:

1760355

Report Number(s):

SAND-2020-11726J
Journal ID: ISSN 0022-3727; 691990; TRN: US2205743

Grant/Contract Number:  

AC04-94AL85000; SC000319; SC0020232; PHY-1902878; NA0003525

Resource Type:

Accepted Manuscript

Journal Name:

Journal of Physics. D, Applied Physics

Additional Journal Information:

Journal Volume: 54; Journal Issue: 4; Journal ID: ISSN 0022-3727

Publisher:

IOP Publishing

Country of Publication:

United States

Language:

English

Subject:

70 PLASMA PHYSICS AND FUSION TECHNOLOGY