Numerical description of a pressure-swirl nozzle spray

Abstract

A B S T R A C T Pressure-swirl nozzles are widely used in both industrial and experimental processes. However, the spray flow fields are difficult to predict due to the complexities of the dense break-up region. Herein, an inflow boundary condition approach is employed whereby droplets are computationally injected at 9 mm downstream of the orifice based on experimentally derived descriptions of the mean droplet and gas velocities, combined with empirical relations for turbulent kinetic energy and dissipation. The gas flow is then predicted with a Reynolds-Averaged Navier-Stokes solution while the particle trajectories are computed with a discrete random walk model. This approach was found to reasonably describe downstream spatial distribution of gas and droplet velocity, with moderate mesh resolution and CPU time. In addition, the evolution of the droplet velocity fluctuations was found to be consistent with turbulent diffusion theory based on the local Stokes numbers and turbulent kinetic energy.

Atomization and Mixing Characteristics of Swirl‐Flow Atomizers in the Refining Industry

“…The dispersion of water into droplets by nozzles is known as atomization [8,9]. Technologies related to swirl atomization have been widely used in numerous fields.…”

Analysis of internal flow and outlet velocity characteristics associated with dust suppression nozzles and their impact on spray field

“…JL York et al 12 indicate that the study of liquid flow within the nozzle is critical for understanding the droplet atomization mechanism. H Mohammadi et al, 13 C Qin and E Loth, 14 and L Wang et al 15 use numerical simulation as a useful means to guide the modification of nozzle shape parameters, with an effort to optimize the atomization effect. It should be noted that velocity is an important parameter to consider during the simulation of internal flow field.…”

Interaction between a hollow‐cone spray and the co‐axial swirling stratified flow in a novel spray pyrolysis furnace

“…In the modelling of spray drying, reliable CFD models have been built which have good validation results with the experiments . Most spray drying modelling is performed using a mixed Eulerian‐Lagrangian approach, in which the flow field is determined by the single phase Reynolds Averaged Navier Stokes (RANS) equations, while the droplets are modelled using the Lagrangian technique . The standard k‐ϵ model has been proven to have enough accuracy in turbulence modelling.…”

“…[10,11] Most spray drying modelling is performed using a mixed Eulerian-Lagrangian approach, in which the flow field is determined by the single phase Reynolds Averaged Navier Stokes (RANS) equations, while the droplets are modelled using the Lagrangian technique. [7][8][9][10]12,13] The standard k-e model has been proven to have enough accuracy in turbulence modelling. Huang et al [8,14] and Mezhericher et al [15][16][17][18] have performed several calculations on a cylinder-on-cone spray chamber, in which the twodimensional and three-dimensional models have predicted values of velocity, temperature, and vapour mass fraction in the spray chamber with reasonable accuracy.…”