Plasma relaxation mechanics of pulsed high power microwave surface flashover
- Center for Pulsed Power and Power Electronics, Department of Electrical and Computer Engineering and Department of Physics, Texas Tech University, Lubbock, Texas 79409 (United States)
Microwave transmission and reflection characteristics of pulsed radio frequency field generated plasmas are elucidated for air, N{sub 2}, and He environments under pressure conditions ranging from 10 to 600 torr. The pulsed, low temperature plasma is generated along the atmospheric side of the dielectric boundary between the source (under vacuum) and the radiating environment with a thickness on the order of 5 mm and a cross sectional area just smaller than that of the waveguide. Utilizing custom multi-standard waveguide couplers and a continuous low power probing source, the scattering parameters were measured before, during, and after the high power microwave pulse with emphasis on the latter. From these scattering parameters, temporal electron density estimations (specifically the longitudinal integral of the density) were calculated using a 1D plane wave-excited model for analysis of the relaxation processes associated. These relaxation characteristics ultimately determine the maximum repetition rate for many pulsed electric field applications and thus are applicable to a much larger scope in the plasma community than just those related to high power microwaves. This manuscript discusses the diagnostic setup for acquiring the power measurements along with a detailed description of the kinematic and chemical behavior of the plasma as it decays down to its undisturbed state under various gas type and pressure conditions.
- OSTI ID:
- 22220642
- Journal Information:
- Physics of Plasmas, Vol. 20, Issue 9; Other Information: (c) 2013 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 1070-664X
- Country of Publication:
- United States
- Language:
- English
Similar Records
Dynamic of ozone formation in nanosecond microwave discharges
Dynamic of ozone formation in nanosecond microwave discharge
Related Subjects
GENERAL PHYSICS
AIR
DIELECTRIC MATERIALS
ELECTRIC FIELDS
ELECTRON DENSITY
ELECTRON TEMPERATURE
FLASHOVER
HELIUM
HIGH-FREQUENCY DISCHARGES
ION TEMPERATURE
MICROWAVE RADIATION
NITROGEN
PLASMA DENSITY
PLASMA DIAGNOSTICS
PULSES
RADIOWAVE RADIATION
RELAXATION
SCATTERING
WAVE PROPAGATION
WAVEGUIDES