WATER-JET PROPELLER Russian patent published in 2001 - IPC

FIELD: shipbuilding; manufacture of propellers for high-speed ships. SUBSTANCE: water-jet propeller has water conduit and impeller arranged inside water conduit and mounted on shaft. Tail section of water conduit is made in form of profiled circular nozzle and is arranged behind ship's transom together with impeller so that its lower edge projects beyond ship's bottom. Inner surface of nozzle is made in form of two round cylindrical surfaces intersecting before impeller. Axes of fore cylinder forms angle together with ship's BL which is equal to minus 3 to plus 1 deg. Axis of aft cylinder coincides with axis of impeller shaft. lateral surface of water conduit upward in way of flow from nozzle is formed as elongation of cylindrical surface of fore portion of nozzle; upper arch of water conduit has surface which is curvilinear along longitudinal axis of fore cylinder of nozzle; this surface passes in each section over line of segment chord of circle of cylinder cross-section. EFFECT: enhanced propulsive characteristics of propeller under all operating conditions of ship. 3 dwg