Studies on the Flame Structure of a Spray Burner : 1st Report, Measurement of Quantities Related to Droplets and Gas within the Flame, and Their Correlations

Abstract

To clearify the flame structure of a spray burner, distributions of droplets, and those of temperature, flow velocity and gas composition were measured within the flame of an air-atomizing burner. The magnesium oxide method providing a shutter mechanism was adopted to detect the droplets. To measure the gas temperature, a suction pyrometer free from the effect of droplets was specially desined. The following were concluded. (1) The flame may be simplified as a model consisting of three regions. Designating them as A, B and C in order of distance from the burner nozzle, A is a region where a heterogeneous mixture containing many droplets is burning; in B, only a combustible gas fed from A is burning continuously; in C, its remainder is burning intermittently. (2) It can be assumed that the droplets in A do not burn individually, but fuel vapor evaporated from them collects and burns like a gas diffusion flame.