An Eulerian model of droplet dispersion in turbulent flow
University of New Brunswick
Industrial sprays are common in many operations where liquid application to surfaces is required. Simulation of spray characteristics and surrounding flow conditions is crucial for maximizing spray efficacy. Traditionally, droplet modelling has been performed using a Lagrangian approach which requires tracking a sufficient number of droplets to form statistical estimates of droplet deposition. Alternatively, an Eulerian-based flow and droplet transport model using the Direct Quadrature Method of Moments (DQMOM) is applied to spray modeling. This model is coupled with the Reynolds Averaged N avier Stokes (RANS) equations and Shear Stress Transport (SST) turbulence model. The method described uses a novel turbulent diffusion coefficient model based on a full parametric study using Lagrangian particle tracking in a uniform, homogeneous and isotropic turbulent flow field. The model results are compared to: 1) Lagrangian tracking predictions of a log-normal particle size distribution injected into a homogeneous, isotropic turbulent flow field, and 2) full-scale experimental wind tunnel measurements in the anisotropic, non-homogeneous wake of a hollow cone hydraulic nozzle.