Atomization and Sprays, Vol.16, No.4, 379-400, 2006
Atomization of gel propellants through an air-blast triplet atomizer
An effort was made to relate the rheological properties of gel propellant simulants with their atomization behavior. The gels were atomized using a triplet impinging air-blast atomizer. The experimental investigation demonstrates that pseudoplastic water gels exhibit spray patterns that resemble those of Newtonian liquids, but they are more difficult to atomize. The Sauter mean diameter decreases along the injector axis and increases with increasing radial coordinate and the angle between the gas jets plane and the horizontal plane. Wide-angle convergent injectors require lower upstream pressure to achieve the same atomization performance with straight injectors. Sauter mean diameter decreases down to a minimum constant value with the increase of the air-to-liquid mass flow rate ratio. Sauter mean diameter increases with increasing gellant content due to the respective increase of the shear viscosin An expression relating the Sauter mean diameter to the injection conditions and the mean apparent viscosity, at the injector exit is presented.