What determines the drop size in sprays of polymer solutions?

The effect of viscoelasticity on sprays produced from agricultural flat fan nozzles is investigated experimentally using dilute aqueous solutions polyethylene oxide (PEO). Measurements the droplet size distribution reveal that polymer addition to water results in formation overall bigger droplets with a broader distribution. median found increase linearly extensional relaxation time liquid and be well captured by simple empirical expression terms non-dimensional Weber Deborah numbers. We show increasing can partly attributed an wavelength flapping motion responsible for sheet breakup, resulting larger ligaments which are formed. also distributions, rescaled average drop size, described compound gamma parameters n m encoding ligament corrugation width distribution, respectively. These saturate values n=4 m=4 at sufficiently high concentrations.