The Collision Behavior of Free Molecules in Combustion Fields

The collision behavior of free molecules in flame is described. A fine particle generating system was adapted for observing the diffusion coefficient by means of dynamic light scattering. Electron microscopic examination of the generating particles shows them to reach a diameter of about 30 nm. From the observed diffusion coefficient and particle radius, it appears that the mean free path in the flame is very short compared with thermodynamical estimation–about one fortieth as long.