Optimum optical parameters of phase Doppler (PDA/PDPA) techniques are investigated in order to reduce error and uncertainty for spray characteristics measurement. Steady spray of gun-type burner and unsteady spray of injector were chosen as experimental systems.
Three optical parameter set up effects were taken into account and these error sources were discussed here. Initial setup parameters influence on measurement results were examined by changing conditions.
In data analysis, it was found that the Sauter mean diameter was not enough to understand mixture formation characteristics, so that a size classified data analysis was demonstrated. Furthermore, slip velocity and velocity fluctuation are shown in 2-D as well as droplet velocity vectors of each classes. Especially, time-dependent phenomena that strongly effected such as unsteady spray, special attentions were paid on bin width (time window) for understanding of spray tip structure.
The pre-measurement was found to be very important and the finding of the optimum set up was the most in dispensable to PDA measurement.