INVESTIGATION ON THE INTERACTION AMONG MULTI-SPRAYS GENERATED FROM PRESSURE-SWIRL ATOMIZERS

The spatial distributions of the Sauter mean diameter (SMD) and the size distribution parameter n in the three-spray including left, center, and right were investigated experimentally in this paper. The observed SMD of the center spray is larger than that of the single spray after the center penetration point (CPP) due to the penetration of the side sprays. However, they tend to be equal far away from the nozzle exit. Downstream of the CCP for the side spray, the SMD increases along the axial direction. At first the SMD of the side spray is larger than that of the single spray but less than that of the center spray. Then with the increase in axial distance, the SMD of the side spray will exceed that of both the center spray and the single spray due to the penetration of the other side spray. Downstream of the initial interference point (IIP), the observed SMD of the integrated spray is less than that of the single spray due to the droplet collision. Near the IIP, the droplets prefer to break up and bounce, but near the CPP, the intrusive large droplets and local small droplets prefer to aggregate into larger droplets. There are two primary mechanisms to affect the local SMD. One is the spatial superposition of the spray from different atomizers, and the other is the droplet collision, although the former mechanism is dominant.