Ignition of a Binary Fuel Droplet by a Propagating Laminar Flame.

Abstract

An experimental study has been made of the ignition process of a binary fuel droplet subjected to a laminar flat flame propagating through a lean homogeneous propane-air mixture at constant pressure. A combustion chamber made of a transparent duct was installed with spark electrodes, a fine quartz fiber to suspend a fuel droplet and a shutter to allow the burned gas to flow out. A high speed video camera was provided for the photographic observation of the droplet ignited by the propagating flame and for the determination of the ignition delay. The ignition delay showed a peak as a function of initial droplet diameter and the diameter at the peak ignition delay decreased with an increase in the n-hexane or the benzene volume concentration. Also evident was that the ignition delay decrased largely with an increase in the n-hexane or the benzene volume concentration.