Accession Number : AD0755693

Title :   Coagulation of Carbon Particles in Premixed Flames.

Descriptive Note : Technical rept.,

Corporate Author : PURDUE UNIV LAFAYETTE IND PROJECT SQUID HEADQUARTERS

Personal Author(s) : Wersborg,B. L. ; Howard,J. B. ; Williams,G. C.

Report Date : DEC 1972

Pagination or Media Count : 36

Abstract : The size distribution, number concentration, and fraction charged of carbon particles at successive stages of formation in a low pressure flat flame were measured using molecular beam sampling involving electrical beam deflection and electron microscopy of beam deposits and an optical absorption technique. Observed cluster-type structure within roughly sperical particles and decreasing particle number concentration following rapid nucleation indicate the particles do indeed coagulate during growth. Particle size and number concentration data confirm this conclusion although the experimental coagulation rate exceeds by a factor of about 10 the kinetic energy collision rate approximately adjusted for elastrostatic forces, based upon the measured extent of particle charging, and Van der Walls attraction. Calculations based upon extrapolation of the experimental coagulation rate constant into the flame region of significant particle nucleation and surface reaction are discussed. (Author)

Descriptors :   (*FLAMES, *PARTICLES), (*COAGULATION, FLAMES), CARBON, PARTICLE SIZE, KINETIC THEORY

Subject Categories : Combustion and Ignition

Distribution Statement : APPROVED FOR PUBLIC RELEASE