357 results about "Jet propulsion" patented technology

A novel pressure-exchange ejector is disclosed whereby a high energy primary fluid transports and pressurizes a lower energy secondary fluid through direct fluid-fluid momentum exchange. The pressure-exchange ejector utilizes non-steady flow principles and both supersonic flow and subsonic flow embodiments are disclosed. The invention provides an ejector-compressor/pump which can attain substantially higher adiabatic efficiencies than conventional ejectors while retaining much of the simplicity of construction and the low manufacturing cost of a conventional ejector. Embodiments are shown which are appropriate for gas compression applications such as are found in ejector refrigeration, fuel cell pressurization, water desalinization, and power generation topping cycles, and for liquid pumping applications such as marine jet propulsion and slurry pumping.

A variable marine jet propulsion system incorporates a motor, a variable-pitch propeller pump in a spherical housing, a variable housing and a variable inlet duct, and a microcontroller. The pump, the nozzle and the inlet are controlled by the microcontroller, which is programmed to control the pump as a continuously variable power transmission for maintaining efficient motor operation, the nozzle for maintaining efficient pump operation, and the inlet for maintaining efficient recovery of the total dynamic head of the incoming water. The spherical pump housing maintains close fits to the propeller vane tips for more efficient operation at all pitches, including zero and reverse pitches. Zero pitch results in no effective pumping action, effectively a true neutral in fluid power transmission. Reverse pitch in combination with the large variable nozzle provides reverse flow and consequently reverse thrust, which eliminates the need for the “backing bucket”.

A tandem blade lattice having characteristics enhanced is provided. In a high pressure ratio blade lattice, inevitable generation of an shock wave is shifted, as much as possible, toward a rear portion of an upper surface of a front blade to inhibit separation from a blade surface from being caused by interference of the shock wave and a boundary layer, and boundary layer control is performed such that a speed, a momentum and the like of a jet flowing from a trailing edge of a lower surface of the front blade onto an upper surface of a rear blade are regulated to obtain a flow along the upper surface of the rear blade, so that separation of the boundary layer on the upper surface of the rear blade is restricted to a vicinity of a trailing edge.

A watercraft has a pivoting, shock absorbing component that absorbs forces applied to its hull. The watercraft includes a hull, a deck coupled to the hull, an engine, and a jet propulsion system movably coupled to the engine. In one embodiment, a forward hull portion couples to the deck and a rearward hull portion movably couples to the deck and/or the forward hull portion. The jet propulsion system mounts to the rearward hull portion, while the engine mounts to the deck. A suspension element is disposed between the hull rear portion and either the deck or the hull forward portion. In another embodiment, the hull and deck are movably coupled to each other.

To provide an engine control unit for facilitating steering control. In particular, the invention relates to a controller of a boat propelled by jetting water pressurized and accelerated by a water jet pump. If a throttle angle of an engine for driving the water jet pump is a predetermined value or less and a steering angle by a steering handlebar of the jet propulsion boat is a predetermined value or more, a throttle valve of the engine is operated in an opened direction and advance angle control is made over the normal ignition timing of the engine.

The stern hull portion of a sea craft through which main exit flow channels extend to projecting jet propulsion nozzles, is provided with facilities for controlled maneuvering of the sea craft, including steering, stopping, negative thrust backing and docking without substantial hydrodynamic loading and with facilitated installation. Such maneuvering control facilities include a secondary flow channel extending from each of the main exit flow channels having two angularly related subchannel branches for pressurized water outflow through gated openings in the hull from which propulsion jets emerge under maneuvering control. Either control of a subchannel diverting flapper, or by use of selective closure gates and a flow diverting flap within the main exit flow channel, maneuvering may be effected in response to inflow through inlet openings in the hull of water that is pressurized before supply to the main exit flow channels.

An automatic trim system for a jet propulsion watercraft is provided. Control electronics are in communication with a steering angle sensor to monitor the steering angle of the watercraft, and evaluate a target setting for the trim taking the steering angle into consideration. Control signals are sent to an appropriate actuating device for adjusting the trim angle accordingly.

The invention discloses a welding process used for a marine water-jet propulsion chute grate. The process comprises the following steps: firstly, grate components are processed well and the margins are pre-preserved; the actual mounting is carried out to define the actual mounting positions and the final sizes of the components; the components are pre-fixed through spot welding; and after checked and passed, the components are welded in the ship chute to form a complete grate. The proper sequence and process parameters are adopted in the welding so as to reduce the internal stress as much as possible; after welding, the whole grate is demounted to repair welding seams and carry out aging treatment and then the grate is remounted so as to further enhance the strength of the grate and reduce internal stress. The invention can better satisfy the technical requirement and precision requirement of manufacturing, mounting and welding the chute grate so as to avoid the cracks or breaking of grate strips caused by the wearing of the grate structure due to ship vibration.

An aircraft has at least two jet-propulsion engines mounted laterally on the fuselage in a symmetrical design in the aft part of the fuselage. Each jet engine is mounted on the fuselage some distance from the vertical plane of symmetry of the aircraft, so that the jet engine, in a so-called half-buried configuration, is partly inside an envelope surface of a theoretical fuselage. The half-buried, jet engines are mounted on a main boom fitted on the vertical plane of symmetry of the aircraft, inside the fuselage in back, of a forward main frame. The tail sections are mounted on the main boom and the boom is integral with structures for transmitting forces into the forward part of the fuselage. The structure is advantageously made of fiber-reinforced composite materials.

The fuel additives of the present invention comprise essentially of about 10-50 weight % of terpene, 0-15 weight % of Alkylene Glycol Ether, and 40-80 weight % of 2-Propanone, 0-20 weight % of Dibasic Methyl Ester and 0-15 weight % of nonyl phenol ethoxylate and 0-15 weight % of mineral oil. This highly effective fuel additives can eliminate the formation of deposits and form air-borne micro-cluster molecules in internal combustion engines, particularly, in the fuel injection system and combustion chamber of such engines.

The invention discloses a pulse jet type underwater robot based on a tubular origami structure, which is composed of a pulse jet mechanism and two steering propulsion mechanisms, wherein the pulse jetmechanism realizes the repetitive process of water storage-water spray-water storage-water spray by impulse jet propulsion. The structure of the two steering propulsion mechanisms is the same, the first steering propulsion mechanism realizes turning to the right and the second steering propulsion mechanism realizes turning to the left; the pulse jet mechanism realizes the functions of water storage and water spraying through the axial expansion and contraction of the tubular origami structure; the tubular origami structure is driven by the rack and pinion mechanism to realize the axial expansion and contraction of the tubular origami structure, the steering propulsion mechanism is driven by the streamlined semi-circular fish fin structure to perform the reciprocating swing to achieve thesteering propulsion function, and the fish fin structure is driven by the swing guide rod mechanism to achieve the reciprocating swing. The invention is a novel underwater robot and has the advantagesof simple structure, fast propulsion speed, flexible steering and the like.

A rocket engine has a combustion chamber and an expansion chamber interconnected by a nozzle. Both chambers and the nozzle are made of carbon fiber reinforced silicon carbide formed as a monolithic rocket engine body or formed in sections bonded to each other to also form such a monolithic rocket engine body. The rocket engine body is mounted in a support structure, preferably made of a metal. The rocket engine body sections are produced by mechanical machining of respective blanks made of C/SiC materials. Cooling channels and/or heat insulation structures are used for heat control. The insulation structures are preferably also made of C/SiC materials or of carbon fiber felts or of graphite film.

A watercraft includes an improved engine control system that enhances the responsiveness of the watercraft and eases watercraft operation. The watercraft includes a propulsion device, such as a jet propulsion unit, and an engine that powers the propulsion device. The engine control system is configured to maintain or increase engine speed under certain operating conditions.

A marine vessel propulsion device includes an engine, a jet propulsion unit, and a reverse gate. The jet propulsion unit includes a jet port arranged to jet water toward a rear of a hull. The reverse gate is arranged to be capable of being changed in opening degree between a fully closed position of covering an entirety of the jet port and a fully opened position of not covering the jet port at all. The reverse gate is arranged to be moved, between the fully closed position and the fully opened position, to a first partially closed position of only partially covering the jet port and a second partially closed position of only partially covering the jet port and being closer to the fully opened position than the first partially closed position.