2023/07/24 by Romain Vallon, Vallon, Romain, Malek Abid +3
Engineering · Environmental Science · #FOS: Physical sciences #Fluid Dynamics (physics.flu-dyn) #Fluid Dynamics and Turbulent Flows #Particle Dynamics in Fluid Flows #Wind and Air Flow Studies
paper · pdf · doi:10.48550/arxiv.2307.12737
openalex publication_date 2023/07/24 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
Jet fragmentation is investigated through a Direct Numerical Simulation campaign using Basilisk (Popinet & collaborators 2013). The simulations span over one order of magnitude of gaseous Weber numbers (13 to 165), i.e. over the second wind-induced and atomization regimes, and the jets develop over distances up to 28 nozzle diameters. The study focuses on the size and velocity distributions of droplets, as well as their joint distribution. Two models derived from different theoretical backgrounds, the statistical description of the turbulence intermittency (Novikov & Dommermuth 1997) and the empirical description of the ligament-mediated fragmentation (Villermaux et al. 2004), are compared for describing the droplet size distribution close to the nozzle. The characteristics of the size-velocity joint distribution are explained using the vortex ring theory (Saffman 1992) which highlights two sources of fragmentation. Finally, the joint histogram of the particulate Reynolds and Ohnesorge numbers is analysed and a normalisation is suggested. It reveals that the delimitations of the droplet phase space, once properly normalised, are self-similar and independent of the gaseous Weber number, both numerically and experimentally.