The location of the onset of rivulet formation in the surface-water flow over a wing with a NACA 4412 airfoil in rainfall rates of 50 mm/h - 160 mm/h is calculated and compared with wind-tunnel experiments. A model is presented in which rivulets form when the surface-tension shear stress between the liquid and the airfoil surface equals the interface shear stress caused by aerodynamic forces on the liquid due to air motion. Surfcae-tension shear stresses are obtained from measurements of surface tension and contact angle at the solid-water interface. Aerodynamic shear stresses are calculated by solution of Reynolds-averaged Navier-Stokes equations. Comparisons of calculated and measured locations of the onset of rivulet formation agreed within about 3 % of chord for wettable and nonwettable surfaces at incidence up to stall for Reynolds numbers of 2.5x105 to 4x105.
Rivulet formation in surface-water flow on an airfoil in rain
Rinnsalbildungen in der Oberflächenwasserströmung auf einem Tragflügel bei Regen
AIAA Journal ; 37 , 1 ; 45-49
1999
5 Seiten, 6 Bilder, 21 Quellen
Aufsatz (Zeitschrift)
Englisch
FLUID DYNAMICS - Rivulet Formation in Surface-Water Flow on an Ainfoil in Rain
Online Contents | 1999
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