Effect of liquid jet diameter on performance of coaxial two-fluid airblast atomizers

In this paper, the effect of liquid jet diameter on performance of coaxial two-fluid airblast atomizer has been investigated with water–air system in a wide region of liquid/gas mass flux ratio (0.137 < m < 15.6). The Sauter mean diameters (SMD) were measured using Malvern Laser Particle Sizer. The experimental results showed that the liquid jet diameter has striking effect on SMD for large m, but has no effect for small m. For a fixed large m, a decrease of SMD with liquid jet diameter was observed first, followed by an increase. A similar non-monotonic trend was also observed between SMD and liquid jet velocity, We, Re, and M (gas/liquid momentum flux ratio) at the same m, respectively. The minimum SMD is obtained when the velocity of liquid jet flow is about 1.5–4.0 m/s. The following correlation for SMD is developed from the measured data:SMD=685.8(ug−3.297ul)−0.4813m0.3665+0.1824dlm.