PROPELLER BLADE Russian patent published in 1997 - IPC

FIELD: shipbuilding; shipboard propellers. SUBSTANCE: propeller blade has suction surface and driving surface which form non- symmetrical contour and profile of blade section with convex-concave center line. Leading edge of blade is concave. Convex section of center line of profile is directed towards suction surface of blade and concave section of center line is directed towards driving surface of blade. Innovation of invention consists in shifting the zone of maximum stress of blade towards its leading edge closer to its elastic center, thus reducing stress of blade and increasing its reliability. Propulsive characteristics are improved by 3 to 5 percent. Thickness of blade may be reduced at retained strength . EFFECT: reduced stress of blade, enhanced reliability, improved propulsive characteristics, reduced thickness of blade at retained strength. 1 dwg