Experimental investigation on spray characteristics of aircraft kerosene with an external-mixing atomizer

A novel external-mixing atomizer capable of producing a non-conical spray was proposed and investigated in this work. The charge-coupled camera (CCD) and phase Doppler particle analyzer (PDPA) were used to study the macroscopic and microcosmic spray characteristics of the liquid aircraft kerosene, respectively. The spray angles from the front view (X-Z plane) and side view (Y-Z plane) were achieved. The results show that the spray angle of this external-mixing atomizer can be significantly different in the two perpendicular directions, but the discrepancy gradually decreases with the increase of the air flow rate. In addition, the distributions of Sauter mean diameter (SMD) and mean axial velocity component Umean at different downstream distances were plotted. The SMD distribution profiles shaped like a bowl with the maximum values occurring close to the boundary of the spray, while the mean axial velocity distribution profiles shaped like a hat with the maximum values occurring in the central region. Furthermore, the spray was divided into two regions according to the major atomization mechanism, including the outer region and central region. The droplet size and velocity in the outer region are mainly influenced by the fuel supply pressure, while in the central region are primarily affected by the air flow rate.