Effect of an alternating electric field on soot formation in diffusional low-pressure counterflow hydrocarbon flames

Effects are investigated of constant and alternating electric and of magnetic fields on the soot formation in plane diffusional acetylene–and benzene–oxygen low-pressure counterflow flames. When electric fields are applied to the flame, reduction in the soot outflow and formation in the flame of dense aggregates shaped like laminae and droplets were observed. It was shown that the soot aggregates possess a skeleton. Alternating electric fields imposed on the flame inhibit skeleton formation and move the aggregate formation process to the later stages of soot aerosol formation, which leads to the production of dense aggregates and reduces the soot outflow. It is concluded that the observed smallest carbon particles (below 1 nm) are the basic structural soot units. In flames permeated by a magnetic field, the structural soot units form chains, from which domains are formed.