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Show POINTING PUN NO. 62 PPI NT IHC rWLVSPN IMSTPunCNT'I PHfr««ETEPS Tine 11-13-10 RESULTS TBOn S N H P L E CONCENTRATION IIZE 0*HO uwtif M 4 .t 261.6 1*0.4 112.• $4.r 64.6 30.2 39.0 30.3 23.7 IS.3 14.9 11.4 9. 1 LOUCf 261.6 ICO.4 112.0 • 4.3 64.6 30.2 39.0 30.3 23. 7 10.3 14.3 11.4 9. 1 slS nOOEL POS-»*f OAT* M.OCK 2 • 0.0034:: 0v CUMULATIVE UT 9ELOU 97. 1 «0.4 40. 1 23. 1 13.3 7.7 4. 4 2.3 1.4 0.0 0.3 0.3 0.2 0. 1 0.1 LTD.iPPING ' M * is*. r> VOLUME UCIOHT IN 0NNO Z.3 20.7 20.2 17.0 9. a s.» 3.3 1.9 1. 1 0.0° 0.3 0.2 0. 1 0.1 0.0 L A M E . H A L V E PN H 1. 30 ENGLAND. LOO B0*C* 4. "4 OBSCURATION • 0- 31 LIOMT COMPUTED 1333 1014 2047 204 3 1991 i0rs 1633 1449 1234 1062 0*4 713 376 4*3 372 ENEPGv MEHiuPEO 1416 1236 2022 202 b 204" 1964 1300 13Z1 1228 994 333 730 603 432 147 uta WEIGHT FPO" '3 Un UN 10 UN. PNT Figure 4: Typical Data Sheet The measurements and their physical interpretation depend on the transparency of the spray, the careful alignment of the optical system, and in the assumptions introduced to predict the drop size distribution from the scattered light intensity distribution. The Rosin-Rammler [11] distribution was chosen to represent the shape of the size distribution and the two free parameters of this distribution are fitted to match the measured light intensity distribution. The procedure is described in detail in [10]. The quality of the data is characterized by the quantity L O G E R R which, for values less that 5.5, guarantees acceptable data. Figure 5 shows the L O G E R R O R versus the obscuration. The majority of the data points lay below L O G E R R = 5.5 indicating data of acceptable quality. However, some data from the spray edge (r=5 c m ) are of poor quality. The spray is very dilute and consists only of very small droplets at the edge. A very narrow size distribution can be found at this location. Since the Rosin-Rammler distribution has difficulties fitting these data accurately, the error introduced is large for locations at the spray edge. Test Parameters and Test Matrix As mentioned above, the goal of the investigation was the identification of swirl and material properties (primarily viscosity) on the atomization quality (represented by the droplet size). Two nozzle geometries were designed, one nozzle generating a swirling spray, and one eliminating the swirl. Both nozzles were operated at four atomization 6 |