RT Journal Article
ID 59d0273d5d7eaa0b
A1 Li, Larry
A1 Green, Sheldon I.
A1 Davy, Martin H.
A1 Eadie, Donald T.
T1 VISCOELASTIC AIR-BLAST SPRAYS IN A CROSS-FLOW. PART 1: PENETRATION AND DISPERSION
JF Atomization and Sprays
JO AAS
YR 2010
FD 2010-12-03
VO 20
IS 8
SP 697
OP 720
K1 atomization
K1 non-Newtonian
K1 cross-wind
K1 coating
AB Viscoelastic liquids, such as paints and coatings, are widely known to be more difficult to atomize than typical Newtonian liquids. What is not known, however, is how such a difference affects spray coating in field conditions. To address this, we have examined the effect of a cross-flow on two different air-blast sprays, one comprising water and the other an industrial coating. Using particle image velocimetry and raw Mie scattering, we measured the penetration and dispersion of both sprays over a wide range of spray:cross-flow momentum-flux ratios: 134 ≤ qab ≤ 1382. For both sprays, increasing the relative momentum-flux of the cross-flow led to reduced penetration but enhanced dispersion. The leeward boundary, meanwhile, consistently outspread the windward boundary, creating a bias for which we have proposed several plausible mechanisms. As for differences between the two sprays, the coating droplets outpenetrated the water droplets because they had lower drag-momentum ratios, due to their larger size. In response to this finding, we have proposed a new regression model for predicting the penetration of sprays differing in mean droplet size. The coating spray also spread later and more abruptly than did the water spray, particularly at low qab. To explain this behavior, we have suggested a physical mechanism based on the delayed breakup of the coating ligaments.
PB Begell House
LK https://www.dl.begellhouse.com/journals/6a7c7e10642258cc,69c42c27335b288b,59d0273d5d7eaa0b.html