Avalanches near a solid insulator in nitrogen gas at atmospheric pressure

Journal Article · Tue Aug 01 00:00:00 EDT 1989 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.343447· OSTI ID:5898178

Mahajan, S M; Sudarshan, T S

The pulsed Townsend (PT) technique was used to record the growth of avalanches near a solid insulator in nitrogen gas at 0.1 MPa. Several other nonconventional techniques for releasing initiatory electrons at the cathode are discussed. In this paper, experimental results of avalanches initiated by illuminating a fast (0.6-ns) nitrogen laser onto the cathode triple junction are presented. Data were recorded with plexiglas, Teflon, high-density polyethylene, low-density polyethylene, Delrin, etc. Effect of surface condition, variation of the distance between insulator surface and the avalanche initiation region, and the effect of a large number of previous avalanches on the avalanche characteristics at a particular voltage were studied. The Townsend primary ionization coefficient, hereafter referred to as growth coefficient (..cap alpha..), and drift velocity (/ital V//sub /ital e//) were evaluated through the PT technique. Results indicate that the avalanche growth in the vicinity of a solid insulator is less than that in an identical plain gas gap. Existence of a nonuniform field as a result of surface charges on the insulator and/or field modifications due to the avalanche space charge are believed to be responsible for this behavior.

• Research Organization: Department of Electrical Engineering, Tennessee Technological University, Box 5004, Cookeville, Tennessee 38505(US); Department of Electrical and Computer Engineering, University of South Carolina, Columbia, South Carolina 29208
• OSTI ID: 5898178
• Journal Information: J. Appl. Phys.; (United States), Vol. 66:3
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
NITROGEN
TOWNSEND DISCHARGE
ATMOSPHERIC PRESSURE
ELECTRICAL INSULATORS
GASES
LASER RADIATION
PLEXIGLAS
POLYETHYLENES
PULSES
TEFLON
ELECTRIC DISCHARGES
ELECTRICAL EQUIPMENT
ELECTROMAGNETIC RADIATION
ELEMENTS
EQUIPMENT
ESTERS
FLUIDS
FLUORINATED ALIPHATIC HYDROCARBONS
HALOGENATED ALIPHATIC HYDROCARBONS
MATERIALS
NONMETALS
ORGANIC COMPOUNDS
ORGANIC FLUORINE COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC POLYMERS
PETROCHEMICALS
PETROLEUM PRODUCTS
PLASTICS
POLYACRYLATES
POLYMERS
POLYOLEFINS
POLYTETRAFLUOROETHYLENE
POLYVINYLS
RADIATIONS
SYNTHETIC MATERIALS
640410* - Fluid Physics- General Fluid Dynamics