EXPERIMENTS ON DROPLET COLLISIONS, BOUNCE, COALESCENCE AND DISRUPTION

There has been a significant effort to understand the events that occu r when two or more droplets collide. The majority of the early work, w hich dates from the 1960s, focused on droplet growth relating to preci pitation and was thus limited to water droplet collision phenomena. Re cently, studies have sought information on the collision behavior of f uel droplets for application to combustion spray systems. Researchers have found distinct differences between the collision behavior of wate r droplets and fuel droplets. The extensive experimental data on the d roplet collision process is reviewed and presented here for both water and fuel droplet collisions. Collision outcomes of bounce, temporary coalescence followed by separation or catastrophic fragmentation and p ermanent coalescence are examined and an effort is made to relate the existing findings to a unified description of collisional droplet beha vior. (C) 1997 Elsevier Science Ltd.