Performance of twin-fluid atomizers with flow impingement

This paper describes the characteristics of twin-fluid atomizers with and without flow impingement. Malvern RT-Sizer and Particle Image Velocimetry (PIV) are used to measure particle size and spray flow field, respectively. Velocity measurement by PIV system indicates that the spray flow is decelerated in the axial direction and accelerated in the radial direction, resulting in a highly interactive flow pattern between particles. It also results in the formation of a large scale vortex and enhances the flow entrainment near the substrate. Results also show that the particle distribution of the atomizer with external substrate is more concentrated, indicating the re-distribution of the spray droplets during the flow impingement. The particle size can be lowered down to 4.51μm under a low injection pressure of 2 bars. It also implies that the flow impingement can be used as the mechanism to control the particle size distribution of the spray flow for various engineering applications.