A spray nozzle is a device to disperse a liquid into a cloud of fine droplets. Spray nozzles are used to achieve two primary functions: increase liquid surface area to enhance evaporation, or distribute a liquid over an area. Many processes require spray systems to apply or use the liquid efficiently.

Spray studies are used to characterize:

• Turbulence and transient events inside the spray nozzle head
• Cone angle, penetration length, symmetry, mixing phenomena and air flow velocity around the liquid sheet
• Droplet size/velocity correlation, droplet sphericity, droplet shape orientation, volume flux etc. in the break-up region, where the liquid sheet is transformed into droplets
• Time/size correlation to gain knowledge of mass transfer phenomena
• Droplet/wall interaction (impinging & ejected)
• Evaporation phenomena