Numerical simulation for spray spatial distribution of swirl nozzle and its target dustfall area prediction.

Abstract

The droplet breakup and distribution of the internal flow field and external spray field of a nozzle were obtained under different pressures. The thickness of the liquid film increased with pressure as a quadratic function. The maximum value of 0.281 mm at 2 MPa decreased to 0.172 mm at 10 MPa, equivalent to 38.8% decrease. The MATLAB was used to obtain the particle size distribution characteristics of the droplets under different pressures. At 2 MPa, droplet breakup dominated the axial interval [0-700 mm]. With the increase of pressure, D₅₀ distribution as a whole continues to decrease, 2-6 MPa change, the particle size reduction is larger, every increase of 2 MPa reduced by about 15%. 6-10 MPa change, the particle size reduction is smaller, every increase of 2 MPa reduced by about 8%. A model to predict the optimal dust reduction areas under varying pressures was developed. The prediction results indicate that at pressures of 5 MPa and 9 MPa, the target dust removal areas were [344 mm, 710 mm] and [424 mm, 942 mm] along the axial direction, respectively.