Bulletin of the American Physical Society
62nd Annual Gaseous Electronics Conference
Volume 54, Number 12
Tuesday–Friday, October 20–23, 2009; Saratoga Springs, New York
Session JT3: Microplasmas and Jets |
Hide Abstracts |
Chair: Leanne Pitchford, CNRS - Universite Paul Sabatier Room: Saratoga Hilton Ballroom 3 |
Tuesday, October 20, 2009 4:00PM - 4:15PM |
JT3.00001: Microdischarge-based pressure sensors utilizing multiple cathodes for operation up to 1000$^{\circ}$C Scott Wright, Yogesh Gianchandani High temperature pressure sensors have uses in numerous industrial sectors including gas turbine engines, coal boilers, internal combustion engines, and oil/gas exploration machinery. Microdischarges are well-suited for high-temperature operation because of the inherently high temperatures of the ionized species that sustain them. This work describes sensors that operate by measuring the change, with pressure, in the spatial current distribution of pulsed DC microdischarges. The spatial current distribution is determined from the current in two cathodes, with different interelectrode spacing, and the differential current is treated as the output. At low pressures, current favors the farthest cathode while at high pressures, the opposite occurs. Two versions of the sensors are reported. The first type uses 3-D arrays of horizontal bulk metal electrodes embedded in quartz substrates with electrode diameters of 1--2 mm and 50--100-\textit{$\mu $}m interelectrode spacing. These devices were operated in nitrogen over a range of 10--2000 Torr, at temperatures as high as 1000$^{\circ}$C. The maximum measured sensitivity was 5420 ppm/Torr, while the temperature coefficient of sensitivity was as low as -550 ppm/K. Sensors of the second type use planar electrodes and have active areas as small as 0.13 mm$^{2}$ with a maximum sensitivity of 9800 ppm/Torr. [Preview Abstract] |
Tuesday, October 20, 2009 4:15PM - 4:30PM |
JT3.00002: Spatial and Temporal Properties of Radiation for Various Electrode Configurations in Arrays of Glass Microchannel Plasma Devices S.H. Sung, H.C. Lee, A.G. Berger, S.-J. Park, J.G. Eden Asymmetric and symmetric structures of microchannel plasma devices having different channel width of 50 -- 200 $\mu $m are fabricated on 0.4 mm thick sodalime glass substrate. The aspect ratio -- channel length to width -- has been obtained up to 500. All microplasmas are stable and well confined for several gas pressures of 200 -- 700 Torr, and gas mixtures including ambient air. The examination for spatially-resolved emission shows the tendency that peak intensity increases with increasing pressure. The peak emission intensity for 100 $\mu $m wide channel plasmas is doubled while increasing pressure from 200 to 600 Torr, but it also depends on geometrical factors. The temporal radiation in 300 -- 800 nm for various pressures also shows different feature when the microdischarge is driven by AC source. It will be reported that the effect of electrode configuration on the properties of microplasmas. [Preview Abstract] |
Tuesday, October 20, 2009 4:30PM - 4:45PM |
JT3.00003: Parabolic Cross-Sectional Al$_{2}$O$_{3}$ Microcavity Devices: Volume Dependent Plasma Characteristics Optimization Je Kwon Yoon, Brian P. Chung, Yeon Joon Moon, Sung-Jin Park, J. Gary Eden Parabolic cross-sectional microcavity arrays having as small as 80 $\mu $m apertures have been reported [1]. As an electrode, $\sim $100 $\mu $m thick aluminum foil is used and wet chemical processes can reduce the thickness of the electrode as thin as 20$\mu $m, varying the volume of the plasma. Due to the controllable electrode height and the electrochemical method introduced previously, dynamic range of aspect ratio from 0.2 to 2.2 can be provided. Plasma volumes from 1.3 to 6.9 pm$^{3}$ are evaluated while the diameters of apertures are kept constant. Plasma characteristics such as Paschen's curve and emission spectrums in Ne and Ne/Xe are investigated below 700 torr. This study can be applied to devices for display. \\[4pt] [1] K. S. Kim, T. L. Kim, J. K. Yoon, S.-J. Park, and J. G. Eden, Appl. Phys. Lett., 94, 011503, 2009. [Preview Abstract] |
Tuesday, October 20, 2009 4:45PM - 5:00PM |
JT3.00004: Investigations of plasma bullets formed in a non-thermal plasma jet in air Julien Jarrige, Erdinc Karakas, Asma Begum, Mounir Laroussi Recent studies have shown that low temperature atmospheric pressure plasma jets are formed by the propagation of small plasma bullets traveling at very high velocities in ambient air. However, the propagation mechanisms are still not well understood. In this paper we report experimental investigations of plasma bullets dynamics. The plasma jet was generated by a dielectric barrier discharge reactor fed with pure Helium. The discharge was driven by high voltage (4-10 kV) short rise time (nanoseconds) pulses at frequencies up to 10 kHz. ICCD camera was used to determine the evolution of the velocity during the different propagation stages of the plasma bullet. Optical Emission Spectroscopy (OES) of the different reactive species (N$_{2}^{\ast }$, N$_{2}^{+}$, He$^{\ast })$ show that the bullet is ring shaped. The active species are mainly formed at the interface between He flow and ambient air. Fluid dynamics simulation was used to study the influence of He flow rate on propagation characteristics, and the results were compared to experimental data. It was found that the HV pulse width and the mole ratio of air in the He flow plays a major role in the extinction of the bullet. [Preview Abstract] |
Tuesday, October 20, 2009 5:00PM - 5:15PM |
JT3.00005: Measurements of the propagation velocity of an atmospheric pressure plasma plume by various method XinPei Lu, Z. Xiong, Q. Xiong, Y. Xian, C. Zou, W. Gong, J. Liu, F. Zou, Z. Jiang, J. Hu, Y. Pan The propagation behavior of atmospheric pressure plasma plumes has recently attracted lots of attentions. In this paper, five different methods are used to measure the propagation velocity of an atmospheric pressure plasma plume. The first method, called the ``current method,'' obtains the propagation velocity of the plasma plume by measuring the currents carried by the plasma plume at different positions. The second method, called ``voltage method,'' obtains the plume propagation velocity by measuring the voltage at different positions along the plasma jet with a voltage divider. The third method, called ``charge method,'' which significant interferes with the plume propagation, estimates the plume propagation velocity by measuring the charges deposited on the surface of a quartz tube. The fourth method, which is noninterference method, obtains the plume propagation velocity by capturing the dynamics of the plasma plume with an ICCD camera. Finally, the fifth method, estimates the plume propagation velocity based on the temporal optical emission intensity measurement of selected species by using a spectroscopy. The experimental results show that plasma plume velocities obtained from the five methods have reasonable agreement with each other. [Preview Abstract] |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2025 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700