Spray characteristics and droplet size distributions from low pressure spray atomisation

An understanding of the physical mechanisms underlying the atomization process from a spray device can reveal important information leading to more effective device design. A commercial nasal spray device exhibiting low pressure atomization was tested to obtain spray formation, its characteristics, droplet size distribution, and droplet velocity. High speed laser photography combined with an in house designed automated actuation system, and a highly precise traversing unit, measurements and images magnified in small field of view regions within the spray was performed. The spray formation was produced from a swirling liquid sheet that separated off into ligaments, and continued to breakup into droplets. These droplets continued to deform as they travel downstream at velocities of up to 20 m/s.