A marine reduction gear makes it possible to reduce the installation space of an electrical rotating machine. A marine reduction gear includes: an input shaft coupled to an output shaft of an engine; an output shaft coupled to a propeller shaft that rotates a screw propeller; a gearbox accommodating an input gear provided on the input shaft and an output gear provided on the output shaft, the gearbox supporting a first bearing that supports the output shaft in a rotatable manner; and an electrical rotating machine including: a central shaft that rotates together with the output shaft; a rotor fixed to the central shaft; and a stator surrounding the rotor. The gearbox supports the stator and a second bearing that supports the central shaft of the electrical rotating machine in a rotatable manner.

A propulsion system for providing a power output is disclosed. The propulsion system may have a transmission configured to provide the power output. The propulsion system may also have at least one first energy conversion machine. Further, the propulsion system may have at least one power unit. The power unit may be operable to selectively drive at least one of the transmission and the at least one first energy conversion machine. The propulsion system may also have at least one second energy conversion machine. The second energy conversion machine may be operable to selectively drive or be driven by the transmission. In addition, the propulsion system may have a power transfer arrangement for transferring power between the first and second energy conversion machines.

A distributed propulsion system is described that includes at least one turbine engine including an engine shaft and at least one mechanically driven propulsor, wherein a propulsor shaft of the at least one mechanically driven propulsor is not co-axial with the engine shaft of the at least one turbine engine and is driven by the engine shaft of the at least one turbine engine. The distributed propulsion system further includes at least one generator driven by rotation of at least one of the engine shaft of the at least one turbine engine or the propulsor shaft of the at least one mechanically driven propulsor. The distributed propulsion system also includes at least one electrically driven propulsor, wherein a propulsor motor of the at least one electrically driven propulsor drives a propulsor fan of the at least one electrically driven propulsor based on electricity produced by the at least one generator.

According to one aspect of the present disclosure, a floating vessel, particularly an LNG carrier, is described. The floating vessel comprises: a gas turbine engine-generator assembly configured to generate a first electrical power and to supply the first electrical power to an electrical distribution system; a steam turbine engine-generator assembly configured to generate a second electrical power and to supply the second electrical power to the electrical distribution system; a propulsion system configured to propel the floating vessel using a propulsion power supplied from the electrical distribution system, wherein the gas turbine engine-generator assembly is configured to generate a maximum first electrical power between 10 MW and 18 MW, particularly between 14 MW and 15 MW at 25 C. According to a further aspect, a method of operating a floating vessel is described.

A marine vessel and a method of operating the marine vessel. The marine vessel includes an electricity generation system having a nuclear reactor and an electrical generator. The nuclear reactor is coupled to the electrical generator to generate electricity. The marine vessel may also include a propulsion system having an engine and a propulsor that receives torque from the engine to move the hull through a body of water surrounding the hull. The marine vessel may be part of a temporary power system having an electrical cable electrically connecting the electrical generator to an onshore electrical distribution system. A plurality of buoys may support the electrical cable between the marine vessel and the onshore electrical distribution system. The method of operating the marine vessel may include starting up the nuclear reactor and maintaining the nuclear reactor in a standby condition, while the marine vessel is underway.

A vessel configured for transporting cargo can be configured to operate in a supercavitation mode, the supercavitation mode including releasing a fluid at least partially over an external surface, diverting at least a portion of the fluid to a propulsion system, and generating propulsion at least in part from the first fluid. In response to traveling in the supercavitation mode, the vessel can travel at high-speeds with a majority of the hull below a surface of a body of water.

A propulsion system includes a power generating unit, a bus line and a propelling line powered by the unit, the unit including a motion generator, and an electric generator driven by the motion generator. The electric generator includes a stator with a first armature for powering the bus line, a second armature for powering the propelling line, a first rotor, driven by the motion generator, common to the first and second armatures. The propulsion system comprises a propulsion unit including a propelling system and an electric motor for driving the propelling system. The electric motor includes a stator having a first winding, powerable by the bus line, and a second winding, powerable by the propelling line. The electric motor includes a second rotor that is drivable by the first and second windings and the propelling line is distinct from the bus line.

A vessel configured for transporting cargo can be configured to operate in a supercavitation mode, the supercavitation mode including releasing a fluid at least partially over an external surface, diverting at least a portion of the fluid to a propulsion system, and generating propulsion at least in part from the first fluid. In response to traveling in the supercavitation mode, the vessel can travel at high-speeds with a majority of the hull below a surface of a body of water.

A water craft comprising: an elongated hull comprising a passageway having an inlet and an outlet; a pump jet disposed within said passageway intermediate said inlet and said outlet; said pump jet being configured to receive water entering said passageway through said inlet and pump said water out of said outlet, whereby to propel said hull through water; a plurality of nozzles disposed on the outer surface of said hull, aft of said inlet, wherein said plurality of nozzles are configured to release a friction-reducing fluid, whereby the friction-reducing fluid displaces water from the surface of said hull so as to diminish friction on the outer surface of said hull and facilitate high speeds.

A submersible vessel comprising: an elongated hull; at least one propeller mounted on a forward end of said hull and adapted to move said hull through water; said at least one propeller being of a size and configuration such that when it is rotated at an appropriate speed, it generates supercavitated water flowing from said at least one propeller and thence along an outer surface of said hull so as to diminish friction on the outer surface of said hull and facilitate high underwater speeds.