LIST OF FIGURES 



Page 



1 - Tip-Vortex Rollup Process 2 



2 - Proposed Spatial Distribution of Vortex Structure: 1 - 



Viscous Inner Region; 2 - Smoothed-Out Spiral, 



Velocity Distribution Essentially Inviscid; 



3 - Tightly Wound Spiral; and 4 - Unrolled 



Portion of Vortex Sheet 5 



3 - Variation of Tip-Vortex Core Axial Velocity w with 



Reynolds Number R 5 



4 - Illustration of Schemes for Alleviating Tip Vortex 8 



5 - Investigative Ranges 10 



6 - Variation of Propeller Tip Vortex Cavitation Index a 



with Advance Coefficient J , with and without Tip 



Pitch Reduction 13 



7 - Variation of Propeller Tip Vortex Cavitation Index as a 



Function of Advance Coefficient for Various Propeller 



Area Ratios 15 



8 - Variation of Efficiency e. Drag Coefficient C , and 



Core Tangential Velocity V. with Tip Porosity for a 



Porous Tip Wing 17 



9 - Variation of Cavitation Index a as a Function of Advance 



Coefficient J for the Bulbous Tip Propeller 20 



10 - Variation of Tip Vortex Vorticity as a Function of Jet 



Momentum Coefficient C. for Linear Mass Injected Tip 23 



11 - Variation of Tip Vortex Rotational Velocity as a Function 



of Wing Outboard Distance for Spanwise Mass Injected Tip ... 24 



12 - Comparison of Spanwise Loading for a Fixed Planar 



Elliptical Planform Foil and a Typical Propeller 



Blade-Variation of Circulation (F/F ) as a 



Function of Span (r/R) ?^^ 28 



