Analysis of the polarity effects in the electrical breakdown of liquids.

Journal Article · Tue Mar 01 04:00:00 EST 2005 · Proposed for publication in Physical Review E.

OSTI ID:948269

Woodworth, Joseph Ray; Qian, J ^[1]; Joshi, Ravindra P ^[1]; Schamiloglu, Edl ^[2]; Gaudet, John A ^[2]; Lehr, Jane Marie

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1. Old Dominion University, Norfolk, VA
2. University of New Mexico, Albuquerque, NM

Electrical breakdown simulations are carried out for liquids in response to a sub-microsecond ({approx}100-200 ns) voltage pulse. This model builds on our previous analysis and focuses particularly on the polarity effect seen experimentally in point-plane geometries. The flux-corrected transport approach is used for the numerical implementation. Our model adequately explains experimental observations of pre-breakdown current fluctuations, streamer propagation and branching as well as disparities in hold-off voltage and breakdown initiation times between the anode and cathode polarities. It is demonstrated that polarity effects basically arise from the large mobility difference between electrons and ions. The higher electron mobility leads to greater charge smearing and diffusion that impacts the local electric field distributions. Non-linear couplings between the number density, electric field and charge generation rates then collectively affect the formation of ionized channels and their temporal dynamics.

• Research Organization: Sandia National Laboratories
• Sponsoring Organization: USDOE
• DOE Contract Number: AC04-94AL85000
• OSTI ID: 948269
• Report Number(s): SAND2005-1504J
• Journal Information: Proposed for publication in Physical Review E., Journal Name: Proposed for publication in Physical Review E.
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
BREAKDOWN
COMPUTERIZED SIMULATION
ELECTRIC FIELDS
ELECTRICAL FAULTS
ELECTRON MOBILITY
FLUCTUATIONS
ION MOBILITY
LIQUIDS