KIEE International Transactions on Electrophysics and Applications

The Korean Institute of Electrical Engineers (대한전기학회)
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Influence of Discharge Conditions on the Ignitability of Lycopodium Streams Due to a Single Capacitance Discharge Spark

  • Park, K. S. (Graduate School of Science and Engineering, Ibaraki University) ;
  • M. Yamaguma (National Institute of Industrial Safety) ;
  • T. Kodama (National Institute of Industrial Safety) ;
  • J. H. Joung (Department of Safety Engineering, Seoul National University of Technology) ;
  • Kim, T. Y. (School of Safety Science, New South Wales University) ;
  • M. Nifuku (Research Center for Explosion Safety, National Institute of Advanced Industrial Science and Technology) ;
  • M. Takeuchi (Department of Electrical and Electronic Engineering, Ibaraki University)
  • Published : 2003.06.01
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Abstract

The influence of discharge conditions, including the resistance of the sparking circuit, the shape of the electrodes and the width of the falling dust on the ignitability of lycopodium streams were investigated. Discharge characteristics and the ignition phenomena were also explored. When a 100 ㏀ resistor was connected in series with the sparking circuit, the lowest level of minimum ignition energy (MIE) was attained for lycopodium streams. Simultaneously, the area where flammable gas generated increased and the duration of flammable gas generation decreased. That is, the ignita-bility of lycopodium streams depended strongly on the discharge power and discharge duration. Electrodes with sharp tips gave smaller MIEs than those with round tips in a capacitive-inductive sparking circuit, while shape made no difference in a capacitive-resistive circuit. Streams that were too narrow required a considerable amount of energy for ignition.

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