Abstract
This paper presents some experimental results of the distance li between the position of first appearance of visible flame and the nozzle tip and the flame growth in a diesel spray using a constant volume combustion chamber.
The first visible flame appears at the turbulent mixing part of the mixing flow region of a spray. The distance li is dependent on the initial pressure po and the number of nozzle holes, but independent on the initial temperature, the oxygen concentration of the charge and the injection quantity. The relation between li and po can be presented by the following experimental expression:
li∝pom (m≅-1) .
The flame growth speed during pre-mixed flame burning period in the diffusion burning is nearly proportional to the oxygen concentration, but the initial temperature, the initial pressure, the number of nozzle holes and the injection quantity have little effects on the flame growth speed.
