Mean Drop Sizes From Fan Spray Atomizers

Abstract

The drop size distributions produced by two geometrically similar fan spray nozzles were measured over an injection pressure range from 1.38 to 10.34 MPa (200 to 1500 psi). The fluids employed were water, water/glycerine mixtures, silicone oils, paint, and paint solvent. These liquids were selected to provide wide ranges in liquid viscosity and surface tension. A nonintrusive Malvern 2600 particle sizer, based on the forward scattering of a 5 mW He-Ne laser beam, was used to yield line-of-sight and cross-sectional drop size distributions. The atomizer was traversed across the laser beam and drop size profiles as a function of distance from the centerline were developed. Analysis of the experimental data showed that the effects of injection pressure and liquid properties on atomization quality are described with good accuracy by the following dimensionally-correct equation. SMDdh = 2.83σμL2ρAdh3ΔPL20.25 + 0.26σρLρAdhΔPL0.25