MARINE PROPELLER Russian patent published in 1998 - IPC

FIELD: transport engineering; marine propellers. SUBSTANCE: marine propeller includes rotor, hub with fairing and hydrodynamic surfaces secured on it with ring located over their periphery. Hydrodynamic surfaces are made in form of axidiagonal blade cascades axially located one in another and separated by intermediate ferrules. Degree of their diagonality increases from periphery to center; number of blades increases from center to periphery. Cross-section of passages formed by surfaces of ring, ferrules, hush and blades increases from inlet to outlet; present blade angle is constant within separate cascade over entire length of passage. EFFECT: enhanced efficiency and avoidance of cavitation. 4 cl, 13 dwg