Centrifugal Atomization: Breakup Mechanisms and Multidisciplinary Applications—A Structured Critical Review

Centrifugal atomization is used to generate droplets or particles in processes ranging from crop protection and metallurgical powder production to rotary-bell coating, combustion, and spray-based product processing. However, comparison across studies is hindered by differences in atomizer geometry, characteristic scales, fluid properties, operating windows, diagnostic methods, and performance metrics. This article presents a structured critical review of centrifugal atomization mechanisms, investigation methods, and multidisciplinary applications. The literature is organized according to operational definitions, atomizer configuration, liquid-film evolution, primary and secondary breakup, experimental and numerical approaches, and application-level performance. Rather than assuming universal phase boundaries, the review synthesizes reported transition criteria for direct-drop, ligament, and film breakup and examines their dependence on geometry, liquid throughput, rotational speed, fluid rheology, surface tension, and surrounding-gas conditions. Across applications, the available evidence indicates that rotational speed and liquid throughput strongly affect film thickness and breakup intensity, but their influence on droplet or particle size remains conditional on the prevailing regime and device geometry. The review further compares the strengths, limitations, validation status, and transferability of commonly used experimental and computational methods. Remaining priorities include standardized definitions of characteristic scales, matched-condition comparisons, uncertainty reporting, benchmark datasets for multiphysics models, and testable criteria for scale-up and cross-application transfer.