Pressure-Swirl and Fan Spray Atomization

Various correlations for mean droplet size generated using pressure-swirl and fan spray atomizers are summarized in Tables 4.4 and 4.5, respectively. In the correlations for pressure-swirl data, FN is the Flow number defined as FN = ml/APlpl) )5, l0 and d0 are the length and diameter of final orifice, respectively, ls and ds are the length and diameter of swirl chamber, respectively, Ap is the total inlet ports area, /yds the film thickness in final orifice, 6 is the half of spray cone angle, and Weyis the Weber number estimated with film 

SMD = 7.3 t° 6V° 2/ ° 25A/y04 Very small variations in and wide variations in effects of atomizer geometry and air properties not included Radcliffe [443] 

SMD = 10-3 (7(6.1 l+0.32xl05FAfp 5 -e xlO APi 5 +1.89x1 0 6APL) Derived from experimental data for 25 different fuels using 6 different simplex nozzles of large Flow numbers Wef 10 Strong effect of t7 no effect of Pl Discrepant with other data Kennedy [445] 

SMD = 2.25 7°2V 5mj 25 Pf5pf25 Consistent with theoretical value and other experimental data r831J4461J4471 Lefebvre [199] 

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