Abstract: This invention relates to a device for use with a ducted propeller system r suppressing gap cavitation between a moving rotor tip and duct wall and more particularly to means for supplying fluid to a ducted propeller whereby cavitation or the noise resulting therefrom may be eliminated.

Abstract: A multistage axial flow pump or compressor comprises at least one stage (10) including a rotor (16) and a stator (20). The rotor (16) is arranged to impart whirl in one direction, while the stator (20) is arranged to impart whirl in the opposite direction. This arrangement is useful in providing comparatively high stage pressures for a given rotor tip velocity with relatively low rotor vane hydraulic loadings. The arrangement is also useful in pumping multiphase fluids.

Abstract: A water jet propelled boat is equipped with a water intake opening, a water jet outlet, and with a mixed flow type impeller, where the above mentioned water intake opening and the above mentioned water jet outlet are connected by a water passage with the impeller in the middle of the water passage, and where the operation of the impeller causes water to be drawn into the water intake opening and expelled through the above mentioned water outlet to propel the boat. The impeller structure is such that a boss section of the impeller has a plurality fins affixed to it, the outside edges of the above mentioned spiral fins are roughly parallel to the axial center of the above mentioned boss, and, the leading and the trailing edges of the fins, with respect to the axial center of the above described boss, slant down toward the above mentioned water outlet opening. At the same time relative speeds, the invention allows a smaller diameter fin unit and, at speeds of 4,000 rpm and over, it offers improved efficiency.

Abstract: A hydrojet turbine drive 10 is described with a first turbine assembly 40 including a first compressor rotor 46 with blades 48 having a water pitch for drawing water into the turbine drive 10. The water is driven against the walls of a housing 18 and into a first stator 56 resulting in a portion of the water breaking down into its gaseous components. The water-gas fluid is reoriented and directed by the first stator 56 into a second turbine assembly 42 including a second compressor rotor 68 the blades 72 of which define a gas pitch. The circular flow therefrom is forced into a second stator 70 whereat additional water is reduced to its gaseous components. The water-gas fluid is directed by the second stator 70 into a third turbine assembly 44 including a third compressor rotor 88 the blades 94 of which also have a gas profile.

Abstract: Multi-functional rotary hydraulic machines and machine systems combining a common rotary drive system with a family of mechanically interchangeable rotary hydraulic machine units having different hydraulic functions.The machines have a static outer casing mounting a prime mover. The prime mover comprises a stator assembly and a rotor assembly. The stator assembly is mounted within and encased by the static outer casing. The rotor assembly comprises a pair of half-shafts by which the rotor assembly is rotatably mounted within the stator assembly. The rotor assembly further comprises mounting and coupling means by which a selected one of a plurality of mechanically interchangeable rotary hydraulic machine units is mounted within and coupled to the rotor assembly for rotation therewith. The rotary hydraulic machine units each have a different hydraulic function. Numerous different hydraulic machine units are described.The machine system of the invention allows a hydraulic versatility not previously possible.

Abstract: The arrangement is of the kind in which at least one water turbine (11) is located in the path of a water source for power generation, comprising a barrage structure (10) which extends across and above the level of the water source (12). The invention is characterized in that the structure is of a cross-sectional width sufficient to absorb static and dynamic loading from said water source and defines only a draught tube (15) for the turbine, in that the turbine is mounted within an inlet casing (19) to form a separate assembly, in that the outlet end of said inlet casing is adapted to be releasably connected to the inlet end of said draught tube, in that locating and locking means (24, 25) are provided for effecting said releasable connection, and in that means (20 to 22) are provided for supporting the weight of the turbine/inlet casing assembly when connected to the draught tube.