RT Journal Article ID 61797301429bb598 A1 Negri, Michele A1 Ciezki, Helmut T1 ATOMIZATION OF VISCOELASTIC FLUIDS WITH AN IMPINGING JET INJECTOR: MORPHOLOGY AND PHYSICAL MECHANISM OF THREAD FORMATION JF Atomization and Sprays JO AAS YR 2017 FD 2017-04-17 VO 27 IS 4 SP 319 OP 336 K1 thread formation K1 Boger fluid K1 viscoelasticity K1 impinging jet injector K1 gelled propellant AB The influence of elasticity on the atomization of viscoelastic fluids in an impinging jet injector has been studied. Tests with several elastic fluids with constant shear viscosity (Boger fluids) have been conducted. The morphology of the breakup has been studied, focusing in particular on the nature of the liquid sheet and of the rim and on the type of breakup of flapping sheets. Regime diagrams have been built, showing the influence of the Weber and elasticity numbers on the morphology. In the second part a physical mechanism has been proposed to explain how the viscoelastic liquid sheet formed by an impinging jet injector breaks up forming threads. The formation of such structures has been correlated with the evolution of the transversal ligaments formed from the disintegration of the sheet. When the elasticity is low, these ligaments break up into droplets due to capillary instability. If the elasticity is so large as to suppress or retard capillary instability, the ligaments are only deformed, leading to the formation of threads. PB Begell House LK https://www.dl.begellhouse.com/journals/6a7c7e10642258cc,2a254986694cc118,61797301429bb598.html