SPRAY CHARACTERISTICS OF A FLOW-BLURRING ATOMIZER

In this study, laser sheet visualization and a phase Doppler particle analyzer are used to obtain the spray characteristics of a flow-blurring (FB) atomizer for a range of air-to-liquid mass ratios (ALRs). For simplicity, the atomizer is operated at ambient conditions of temperature and pressure using liquid water and air. An air-blast (AB) atomizer is also investigated as the baseline for comparison. Results show significant difference in distributions of the Sauter mean diameter (SMD) and mean and rms axial velocity for the two atomizers operated at a given ALR. The FB atomizer produces (i) droplets of smaller SMDs and smaller SMD range over the spray volume, (ii) higher mean and rms axial velocities in the center region, and (iii) a narrow spray with spray angle nearly independent of the ALR, as compared to the AB atomizer. Results show that the FB atomizer can effectively atomize liquids at relatively low ALRs compared to the AB atomizer, while reducing the pressure drop penalty in the atomizing air line. These features make the FB atomizer a useful concept for low-emission combustion of liquid fuels.