Abstract: A watercraft includes a jet propulsion system having a venturi unit and an impeller. The impeller is rotatable in a forward direction for propelling water rearward out of the venturi unit, and a reverse direction for propelling water forward through the venturi unit. A bailer-siphon system of the watercraft includes a fluid conduit defined in part by a valve, the fluid conduit having a fluid inlet in the motor compartment and a fluid outlet at the venturi unit. The valve is operable between an open position in which the valve fluidly connects the fluid inlet to the fluid outlet, and a closed position in which the valve fluidly disconnects the fluid inlet from the fluid outlet. The valve is in the open position when the impeller rotates in the forward direction. The valve is in the closed position when the impeller rotates in the reverse direction.

Abstract: A marine vessel engine in which moving parts found in conventional marine engines are eliminated, wherein such engine is used for the propulsion of marine vessels. In the marine vessel engine, no lubrication or cooling is required, and a column of water replaces the conventional piston in a cylinder of the engine, wherein such water column partially fills such cylinder. The marine vessel engine comprises a cylinder, a bent tube with a plurality of openings and two ends, a flapping member, at least one solenoid valve, and an exhaust. In operation of the marine vessel engine, a column of water fills the cylinder through the bent tube openings, and is purged outside from the cylinder through the flapping member. The at least one solenoid valve controls the flow of a power source into the cylinder.

Abstract: A propulsion system for watercraft that uses steam generated from low energy reactor to enable long range high power propulsion. The system preferably uses steam generated from a low energy reactor to provide on-demand steam generated without external power.

Abstract: A marine propulsion system comprising, in one embodiment: a fuel-filled tank; an air compressor that generates compressed air; an engine that receives fuel from the tank, wherein the air compressor is powered by the engine; and at least one hot gas generator that receives compressed air from the air compressor, the hot gas generator comprising: (a) a combustion chamber having an inlet and an outlet, the compressed air injected into the combustion chamber at the inlet, the combustion chamber adapted to produce hot gas; (b) an injection nozzle that receives fuel from the tank, the injection nozzle positioned proximate to the inlet of the combustion chamber, the injection nozzle adapted to spray the fuel into the combustion chamber; and (c) an exhaust Coanda nozzle positioned at the outlet of the combustion chamber through which the hot gas produced in the combustion chamber is discharged from the hot gas generator.

Abstract: A jet propulsion device and method for controlling movement of the jet propulsion device, where liquid inlets are positioned at a distance from the surface of the device. Preferably, the inlets are positioned in the stabilizing fins of the device. When the device reaches a certain speed, a Riabouchinsky cavity forms around the device, and the radius of the Riabouchinsky cavity is substantially equal to the distance between the inlets and the longitudinal axis of the device.

Abstract: Clean energy powered surfboard having various advantages that make for easy to learn, easy to use, safer, exciting, high performance, environmentally friendly surfing on any ocean wave in the world. The various embodiments include novel motor, turbine, or electric motor generator surfboards comprising hydrogen or electric-powered motors, which can be switch-activated and which drive jet pumps. Energy can be stored as compressed gas, including air and hydrogen. Energy can be stored in novel capacitors that are incorporated in the body of the surfboard. Energy can be generated by solar or water power while surfing or by passing waves, for example, while waiting for a big wave. An output jet provides thrust to catch a wave, to return to the wave breaks, or to avoid a hazard. A novel fin output jet increases stability and maximizes thrust. Self-contained, self-recharging embodiments are low cost, lightweight, safer, and good for the environment.

Abstract: A hydrogen generation apparatus for an underwater vehicle is presented, the apparatus including a hydrolysis reaction compartment, a mass of solid lithium hydride disposed in the compartment, inlet and outlet structure for passing sea water through the compartment to generate steam, lithium hydroxide and hydrogen gas, a condenser for condensing out the steam and retaining the condensate and lithium hydroxide, and a tank for collecting the hydrogen gas, the tank having outlet structure for discharging the hydrogen gas to a vehicle propulsion system.

Abstract: A stabilizing device for a supercavitating vehicle that isolates re-entrant jet flows of liquid from its cavity. The device has a receiving means positioned on the supercavitating vehicle where the re-entrant jet flow impinges on the supercavitating vehicle. An exit means is joined to the receiving means for carrying the received re-entrant jet flow out of interference with the cavity. The exit means includes an exhaust nozzle joined to the aft of the supercavitating vehicle and a re-entrant jet nozzle positioned in communication between the receiving means and said exhaust nozzle transferring said received re-entrant jet flow into the exhaust nozzle. This stabilizes the cavity and improves controllability and maneuverability of the supercavitating vehicles while also reducing the gas ventilation required to maintain the cavity. Furthermore, this reduces self-generated noise allowing improved operation of acoustical sensors incorporated in the vehicle.

Abstract: A portable bow thruster for use on the bow of a boat in a body of water having a water line. The bow thruster includes a blower assembly for producing an air flow to provide thrust, an exhaust air duct for expelling the air flow from the blower assembly, pivoting means for pivoting the bow thruster in the clockwise and counterclockwise directions, support means for supporting the blower assembly, and a mounting assembly for mounting the bow thruster to the bow of the boat.

Abstract: A water craft that is made in three units which are connected together. The dimensions of the units can be varied to carry different size users. A motor that forces air through a tube is mounted in one of the units and air passageways lead from the motor to another unit. The water craft has two different steering mechanisms and exterior fins to control the craft.

Abstract: A portable bow thruster for use on the bow of a boat in a body of water having a water line. The bow thruster includes a blower assembly for producing an air flow to provide thrust, an exhaust air duct for expelling the air flow from the blower assembly, pivoting means for pivoting the bow thruster in the clockwise and counterclockwise directions, support means for supporting the blower assembly, and a mounting assembly for mounting the bow thruster to the bow of the boat.

Abstract: A waterjet drive engine for the propulsion of large ships includes an elongated water conduit having a rearwardly directed exhaust portal, a forward extremity having a water intake portal, and a middle portion of larger diameter than the diameter of the exhaust portal. A hollow axially symmetrical chamber is centrally positioned within the middle portion, defining therewith an annular interstitial zone through which ambient water is caused to flow. A shaft driven by the ship's power system extends into the chamber and is provided with a circular array of propulsion blades positioned within the interstitial zone and adapted to force water rearwardly. A plurality of nozzles enter the chamber and direct high pressure steam toward the exhaust portal. The effect of the steam is to add an augmenting force to the rotative motion of the shaft.

Abstract: An underwater two-phase ramjet engine propulsion unit, including an inlet for receiving a flow of water, compressed gas injector for injecting compressed gas into the flow of water, a mixing chamber for mixing the compressed gas with the flow of water to provide a two-phase flow of working fluid and a nozzle for accelerating the two-phase flow of working fluid so as to generate a two-phase jet. The propulsion unit can be implemented with a fixed geometry or with a variable geometry. The propulsion unit includes a supersonic gas injector as well as a subsonic gas injector. The propulsion unit includes a control system for controlling the compressor, supersonic gas injector, the subsonic gas injector, the geometry of the propulsion unit, and the direction of the thrust vector.

Abstract: Disclosed is a water jet propulsion device for divers and diver equipment. forward pressurized air chamber and a rearward water containing chamber are positioned inside a cylindrical housing and are separated by a flexible membrane which is adjacent to a conical deformation plate. On opening a valve located in communication with the water containing housing, pressurized air in the air chamber forces water from the water chamber through a nozzle to the exterior of the housing until the flexible membrane expands to bear against the conical rearward deformation plate. The device is thus moved in a forward direction along with its attached swimmer or equipment.

Abstract: An underwater two-phase ramjet engine propulsion unit, includes an inlet for receiving a flow of water, compressed gas injector for injecting compressed gas into the flow of water, a mixing chamber for mixing the compressed gas with the flow of water to provide a two-phase flow of working fluid and a nozzle for accelerating the two-phase flow of working fluid so as to generate a two-phase jet. The propulsion unit can be implemented with a fixed geometry or with a variable geometry. The propulsion unit includes a supersonic gas injector as well as a subsonic gas injector. The propulsion unit includes a control system the controlling the compressor, supersonic gas injector, the subsonic gas injector, the geometry of the propulsion unit, and the direction of the thrust vector.

Abstract: A sliding-blade water jet propulsion apparatus has an oval-shaped chamber and a water channel extending generally tangential to the chamber with a cylindrical rotor rotatably mounted eccentrically in the chamber. The rotor has at least two rectangular blades slidably mounted in slots extending through the cylindrical rotor in mutually perpendicular relation and each blade is independently movable relative to the other in a radial direction. Each blade has a guide element extending from opposed sides and through the opposed end walls of the rotor which are slidably received in guide grooves in the chamber end walls. The guide elements traveling in the guide grooves cause the blades to extend and retract radially with their outer ends following the inner periphery of the chamber side wall and a portion of the water channel with a constant clearance.

Abstract: A hydrodynamic propulsion device possessing an expansion chamber located downstream of a cross-sectional widening for the inflow of a medium which is to be expelled through a discharge nozzle. The propulsion device is constructed as a static propulsion mechanism without movable components, in that the gaseous operating medium is produced in the propulsion device through the reaction of a hydrofuel, such as NaK with water.

Abstract: The present invention relates to a turbo kick board. The turbo kick board includes, a base, propellers attached to the base to make the base stop and go, and a rudder attached to the base to make the base turn right and left.

Abstract: A water jet propulsion apparatus creates a high speed water jet rearwardly through a duct in a hull by injecting air and water into the duct from at least one injection port, thereby to impart a thrust to the hull. The need of forming protrusions such as an impeller within the duct thus is eliminated, and the resistance loss of the jet is minimized. Propulsion efficiency is improved remarkably and noise is reduced, while at the same time course stability is improved.

Abstract: A twin-hulled ship is powered by a gas turbine engine in each hull, the engine being located near the waterline in vertical alignment with a position outboard of the superstructure's internal sidewall, but preferably inboard of the superstructure's external sidewall. This is facilitated by the outward bulge of the hull relative to the superstructure's external sidewall. An air inlet filter bank is mounted in the side of the superstructure sufficiently far above the waterline to avoid swamping. Air intake ducting leads from the filter bank to the engine, and exhaust ducting leads from the engine to an exhaust outlet at a higher level than the filter bank. This arrangement enables intrusion of intake and exhaust ducting into the main loading deck space to be avoided while minimizing deviation of intake and exhaust ducting from a straight line path.

Abstract: Break-up activity of water by injection of hot propellant gas into channels f a thrust expansion engine is suppressed to prevent rapid cooling of the gas, utilizing one or more methods including injection of a secondary inflow of the propellant gas and/or the water under lower pressures into the channels, injection of a viscosity enhancer and/or surfactant into the inflow stream of the water and restricting outflow of the water from the channels by means of convergent nozzles.

Abstract: The invention defines a propulsion system for an underwater vehicle. More particularly, the invention describes a turbo-hydroduct propulsion system which operates on stored, high energy fuel. The fuel is combusted and powers a turbopump which pressurizes ingested water to a very high pressure. The pressurized water is subsequently exhausted from the vehicle to produce thrust.

Abstract: Propulsion for boats (10) by jets of compressed air inside a pair of parallel longitudinal channels (11) open underneath, placed below the hull, substantially horizontal, one on each side of a third wider axial channel (13) suitable for formation, as a consequence of the movement of said boat, of a cushion of air that sustains the hull when sliding over the water.

Abstract: An engine or motor is attached in a driving relationship to a water moving device, such as a pump, and a thrust outputing portion, such as a nozzle. Heat generated by and rejected by the engine or motor is passed into the pump base for dissipation into the outputtted jet stream. A supply of gas, such as air, and/or exhausted gases from the motive source is ejected around the outputted water stream in a critically defined boundary layer to reduce (1) against-the-hull turbulence induced by the ejected water flow, (2) water jet stream or thrust energy losses (3) vessel afterbody wake losses, (4) propulsion system underwater noise created by the ejected water stream (acoustical isolation), and (5) the contact friction of water born debree against the vessel hull.

Abstract: A steering and propulsion system for a ship, including two side by side, fore and aft pipes underneath a ship's hull, and compressed air or steam delivered through tubes around an exterior of the hull to the two pipes, and controls to eject forwardly or rearwardly out from the pipes.

Abstract: A propulsion system for an underwater vehicle includes a solid propellant gas generator producing gas which drives a gas turbine. The turbine drives one, or alternately two, centrifugal pumps which induct sea water from intake ports and supply it under pressure through a passage to passages leading to tip nozzles in the blades of a propeller which drives the vehicle, thereby using the reaction force from the tip nozzles to drive the propeller. Exhaust gas, after driving the turbine, is conducted through a conduit and to an annular chamber where it is cooled by means of a spray of sea water, thus condensing the steam present and reducing the volume of exhaust gas.