Droplets, Sprays and Aerosols: Vol. I. Principals of Atomization

This book offers a comprehensive theoretical analysis of liquid atomization and spray formation, detailing the complex processes involved in the breakup of liquids. Atomization encompasses multiple stages of liquid disintegration, beginning with the formation of waves on the liquid surface. These waves, driven by factors such as the high relative velocity between the liquid and surrounding gas, can amplify, extend from the core flow, and eventually disintegrate into cylindrical or sheet-like ligaments. These ligaments, in turn, may become unstable and fragment into droplets, which can further deform and break into smaller droplets due to drag forces or collisions with other droplets or solid surfaces. The underlying physics of these phenomena can be distilled into several key liquid instability processes, including the instabilities of liquid sheets, jets, and droplets. These are predominantly governed by the Kelvin-Helmholtz, Rayleigh-Plateau, and Rayleigh-Taylor instabilities, which arise due to differences in velocity between the liquid and its surrounding gas, capillary forces, and the acceleration of one fluid relative to another, respectively. Additionally, droplet-droplet collisions and droplet impacts on solid surfaces play crucial roles in spray dynamics. Following a collision, droplets may coalesce into larger droplets or shatter into smaller ones, with phenomenological models predicting the resulting droplet sizes. Similarly, when droplets impact solid surfaces, they may spread, splash, or bounce, with models provided to predict these outcomes in the context of atomization.