RT Journal Article ID 35c6a37a2b847b50 A1 Lee, Joshua A1 Basu, Saptarshi A1 Kumar, Ranganathan T1 COMPARISON AND CROSS-VALIDATION OF OPTICAL TECHNIQUES IN DIFFERENT SWIRL SPRAY REGIMES JF Atomization and Sprays JO AAS YR 2013 FD 2013-10-01 VO 23 IS 8 SP 697 OP 724 K1 hydraulic nozzles K1 PDPA K1 PIV K1 droplet distribution K1 shadowgraphy AB This paper deals with an experimental study of pressure-swirl hydraulic injector nozzles using non-intrusive optical techniques. Experiments were conducted to study atomization characteristics using two nozzles with different orifice diameters, 0.3 mm and 0.5 mm, and injection pressures, 0.3−3.5 Mpa, which correspond to Reynolds number (Rep) = 7,000−45,000, depending on nozzle utilized. Three laser diagnostic techniques were utilized: Shadowgraph, PIV (Particle Image Velocimetry), and PDPA (Phase Doppler Particle Anemometry). Measurements made in the spray in both axial and radial directions indicate that velocity, average droplet diameter profiles, and spray dynamics are highly dependent on the nozzle characteristics and injection pressure. Limitations of these techniques in the different flow regimes, related to the primary and secondary breakups as well as coalescence, are provided. Results indicate that all three techniques provide similar results throughout the different regimes. Shadowgraph and PDPA were possible in the secondary atomization and coalescence regimes while PIV measurements could be made only at the end of secondary atomization and coalescence. PB Begell House LK https://www.dl.begellhouse.com/journals/6a7c7e10642258cc,4027ccd04637b38c,35c6a37a2b847b50.html