Effect of the drop size distribution of fuel spray on ignition phenomenon

Abstract

The ignition of fuel spray is affected by various factors, i.e., temperature, pressure, equivalence ratio, droplet diameter, number density of droplets, air velocity, ignition energy, and so on. In order to clarify the effects of spray characteristics on spray ignition phenomenon, there have been many researches. However, the effect of drop size distribution on spray ignition has not been studied yet because it is difficult to control drop size distribution independently with other spray characteristics. In this study, it is aimed to clarify the effect of drop size distribution of fuel spray on ignition phenomenon, using drop size distribution control technique developed by the authors. The results of this study clearly show that the ignition probability decrease with the increase of standard deviation of drop size distribution under the constant mean drop size and concentration condition. In addition, the decrease ratio of ignition probability decreases by the decrease of average fuel spray concentration. The results also show that flame area decrease with the increase of the standard deviation of drop size distribution.