skip to main content

SciTech ConnectSciTech Connect

Title: Self-induced gaseous plasma as high power microwave opening switch medium

Self-induced gaseous plasma is evaluated as active opening switch medium for pulsed high power microwave radiation. The self-induced plasma switch is investigated for N{sub 2} and Ar environments under pressure conditions ranging from 25 to 700 Torr. A multi-pass TE{sub 111} resonator is used to significantly reduce the delay time inherently associated with plasma generation. The plasma forms under the pulsed excitation of a 4 MW magnetron inside the central dielectric tube of the resonator, which isolates the inner atmospheric gas from the outer vacuum environment. The path from the power source to the load is designed such that the pulse passes through the plasma twice with a 35 ns delay between these two passes. In the first pass, initial plasma density is generated, while the second affects the transition to a highly reflective state with as much as 30 dB attenuation. Experimental data revealed that virtually zero delay time may be achieved for N{sub 2} at 25 Torr. A two-dimensional fluid model was developed to study the plasma formation times for comparison with experimental data. The delay time predicted from this model agrees well with the experimental values in the lower pressure regime (error < 25%), however, due to filamentary plasma formation at higher pressures, simulatedmore » delay times may be underestimated by as much as 50%.« less
Authors:
 [1] ;  [2] ; ; ;  [1] ;  [3]
  1. Center for Pulsed Power and Power Electronics, Department of Electrical and Computer Engineering, Texas Tech University, Lubbock, Texas 79409 (United States)
  2. (China)
  3. Key Laboratory for Physical Electronics and Devices of the Ministry of Education, Xi'an Jiaotong University, Xi'an 710049 (China)
Publication Date:
OSTI Identifier:
22408370
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 4; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ARGON; CONTROLLED ATMOSPHERES; DIELECTRIC MATERIALS; EXCITATION; EXPERIMENTAL DATA; FLOW MODELS; MAGNETRONS; MICROWAVE RADIATION; PLASMA DENSITY; PLASMA SWITCHES; PRESSURE RANGE KILO PA; PRESSURE RANGE MEGA PA 10-100; PULSES; RESONATORS; TIME DELAY; TWO-DIMENSIONAL CALCULATIONS