DEVICE FOR REDUCTION OF HYDRAULIC RESISTANCE OF WATER CONDUIT OF SHIPBOARD WATER-JET PROPELLER Russian patent published in 2007 - IPC B63B1/34 B63H11/103 

FIELD: shipbuilding; designing water conduits for water-jet propellers.

SUBSTANCE: proposed device has pipe line with porous members over perimeter of inlet opening of water-jet propeller conduit; it is connected via pipe line with equipment used for preparation of working medium which is fed to boundary layer on inner skin of water conduit. This equipment is provided with transonic jet apparatus in form of mixer-pump; used as working medium is gas-and-water or vapor-and-water two-phase mixture generated in mixer; fraction of gas (air, vapor) ranges from 20 to 90%. First inlet of mixer is connected with water (sea water for example) source by means of pipe line fitted with metering unit. Second inlet is connected with gas or air (vapor) source by means of pipe line provided with metering unit. Pipe line with porous members consists of one or several self-contained parts with common or individual mixers. Slots may be provided inside water conduit over perimeter of one or several cross sections in water conduit skin; each slot is provided with manifold which is connected with mixer by means of pipe line. Slot and manifold may be made from several self-contained sections provided with their own pipe lines and metering units for delivery of two-phase liquid.

EFFECT: simplification of working medium generating equipment; continuous operation of water conduit during operation of propeller; reduction of hydraulic resistance of friction in water conduit; increased running speed; enhanced efficiency; saving of fuel.

3 cl, 2 dwg