skip to main content

Title: Effect of a uniform electric field on soot in laminar premixed ethylene/air flames

The effect of a nominally uniform electric field on the initially uniform distribution of soot has been assessed for laminar premixed ethylene/air flames from a McKenna burner. An electrophoretic influence on charged soot particles was measured through changes to the deposition rate of soot on the McKenna plug, using laser extinction (LE). Soot volume fraction was measured in situ using laser-induced incandescence (LII). Particle size and morphologies were assessed through ex situ transmission electron microscopy (TEM) using thermophoretic sampling particle diagnostics (TSPD). The results show that the majority of these soot particles are positively charged. The presence of a negatively charged plug was found to decrease the particle residence times in the flame and to influence the formation and oxidation progress. A positively charged plug has the opposite effect. The effect on soot volume fraction, particles size and morphology with electric field strength is also reported. Flame stability was also found to be affected by the presence of the electric field, with the balance of the electrophoretic force and drag force controlling the transition to unstable flame flicker. The presence of charged species generated by the flame was found to reduce the dielectric field strength to one seventh that ofmore » air. (author)« less
Authors:
;  [1] ;  [2] ; ; ;  [3]
  1. Key Laboratory of Thermal Science and Power Engineering of Ministry of Education, Department of Thermal Engineering, Tsinghua University, 100084 Beijing (China)
  2. School of Mechanical Engineering, Centre for Energy Technology, The University of Adelaide, S.A. 5005 (Australia)
  3. School of Chemical Engineering, Centre for Energy Technology, The University of Adelaide, S.A. 5005 (Australia)
Publication Date:
OSTI Identifier:
21328633
Resource Type:
Journal Article
Resource Relation:
Journal Name: Combustion and Flame; Journal Volume: 157; Journal Issue: 7; Other Information: Elsevier Ltd. All rights reserved
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; SOOT; AIR; ETHYLENE; ELECTRIC FIELDS; LAMINAR FLAMES; PARTICLE SIZE; CHARGED PARTICLES; ELECTROPHORESIS; MORPHOLOGY; OXIDATION; SAMPLING; DEPOSITION; DISTRIBUTION; DRAG; STABILITY