Dimensional analysis of droplet size and ligament length during high-speed rotary bell atomization
Lutz Gödeke, Walter Oswald, Norbert Willenbacher, Peter Ehrhard
Abstract
Abstract Modern spray-coating processes are based on high-volume, low-pressure, airless atomization or high-speed rotary bell atomization, often assisted by electrostatic charging to increase the transfer efficiency. The process from the liquid film flow beneath the bell, through ligament formation and consecutive disintegration to droplet deposition, has been constantly explored during the evolution of automotive spray coating. This work proposes a set of dimensionless groups that fully describe the process from film flow to ligament disintegration, including shear and elongational flow effects during atomization of particle laden, shear thinning, viscoelastic fluids.
Topics & Concepts
Materials scienceViscoelasticityDimensionless quantityMechanicsCoatingComposite materialFlow (mathematics)PhysicsFluid Dynamics and Heat TransferElectrohydrodynamics and Fluid DynamicsPlant Surface Properties and Treatments