An engine device including: an intake manifold configured to supply air into a cylinder; an exhaust manifold configured to output exhaust gas from the cylinder; a gas injector which mixes a gaseous fuel with the air supplied from the intake manifold; and a main fuel injection valve configured to inject a liquid fuel into the cylinder for combustion. At the time of switching the operation mode from one to the other between a gas mode and a diesel mode, an instant switching to the diesel mode is executed when the engine rotation number is determined to approach the upper limit value which leads to an emergency stop of the engine device.

A buoyant vessel having a hull and a drive system mounted to the hull, the system having a rectifier, a generator, an AC bus in communication with shore power or a charging system and the rectifier, a DC bus in communication with the rectifier, at least one energy storage system, an inverter, a prime mover, a load regenerating device, and a control and monitor system which has predefined specifications for at least one of: storage units of at least one energy storage system; stored therein and wherein the control and monitor system is adapted to: automatically control the DC/DC converters, relieve a current draw from one or more storage units, provide charging current, and automatically draw power and redirect energy.

An LNG carrier which uses natural gas generated by vaporization of LNG as propulsive fuel and including cargo tank, spray apparatus, and carrier communication device; land-based equipment including land-based communication device and processing device; processing device including: first vapor quantity estimating section which estimates total quantity of natural vapor generated from the LNG remaining in the cargo tank in a case where the LNG carrier is traveling on planned ballast course, based on sea weather data; a second vapor quantity estimating section which estimates a total quantity of spray vapor generated by performing spraying operations in a case where the LNG carrier is traveling on planned ballast course, based on the sea weather data; and heel quantity calculating section which calculates required heel quantity, by summing the total quantity of natural vapor and spray vapor, and the land-based communication device transmits the required heel quantity to the carrier communication device.)

The invention relates to a marine surface vessel (1), in particular a passenger ship, extending in a longitudinal direction between a bow (2) and a stern (3), comprising least one power providing apparatus (6) operatively connected to at least one propulsion unit (7) for propulsion of the vessel, a fuel tank arrangement (8) for storing gaseous fuel in a liquid phase, connected to the power providing apparatus (6) by means of a gas supply system for running the power providing apparatus (6), and a plurality of decks (91-98) distributed vertically, one above the other, the fuel tank arrangement (8) comprising two tank sub-arrangements (81, 82), each tank sub-arrangement comprising at least one gaseous fuel tank (811, 812, 821, 822), each fuel tank extending vertically past at least two of the decks (92-95), and at least two of the decks (92-95), past which the fuel tanks (811, 812, 821, 822) extend, each presents a passageway (941) extending between the tank sub-arrangements (81, 82).

A system is disclosed including but not limited to a processor; a hybrid power source for servicing a system load, the hybrid power source comprising a natural gas engine, a diesel engine and a battery; a linear computer program comprising, instructions determining a current system load serviced by power provided from the hybrid power source; instructions to determine a current operating state for the natural gas engine, the diesel engine and the battery; instructions to use linear programming to determine a new operating state for the natural gas engine, the diesel engine and the battery to reduce for power consumption servicing the current system load the natural gas engine, the diesel engine and the battery; and instructions to replace the current operating state for the natural gas engine, the diesel engine and the battery to the new operating state for the natural gas engine, the diesel engine and the battery.

A gas engine is provided that suppresses fluctuation of the actual air-fuel ratio even when a load fluctuates. A gas engine (1) in which at least one opening degree (D) selected from the opening degree of an air supply valve (5a) and the opening degree of a bypass valve (5b) is corrected so that an adequate target air-fuel ratio (t) is achieved, wherein a target gas pressure (Pgt) and a target gas-jetting time (Tt) of a fuel gas are calculated on the basis of fluctuations of an actual load (L), the gas pressure is corrected on the basis of the target gas pressure (Pgt), and at least one opening degree selected from the opening degree of the air supply valve and the opening degree of the bypass valve is corrected on the basis of the amounts of change in the target gas pressure (Pgt) and the target gas-jetting time.

A watercraft and method for operating the watercraft, wherein the watercraft includes an electrical system that is present in a space that has an atmosphere that differs from air, where the space is formable by a pressure hull, where the atmosphere contains, for example, an inert gas, and where the space having the electrical system is filled with the atmosphere.

An engine device (21) including: an intake manifold (67) configured to supply air into a cylinder (77); an exhaust manifold (44) configured to output exhaust gas from the cylinder (77); a gas injector (98) which mixes a gaseous fuel with the air supplied from the intake manifold 67; and a main fuel injection valve (79) configured to inject a liquid fuel into the cylinder (77) for combustion. At the time of switching the operation mode from one to the other between a gas mode and a diesel mode, an instant switching to the diesel mode is executed when the engine rotation number is determined to approach the upper limit value which leads to an emergency stop of the engine device.

A ship includes a main pipe that guides CNG whose pressure is increased by an LNG pump to the engine; a pressure sensor that measures the pressure of CNG to be supplied to the engine; a pressure adjustment valve that adjusts the pressure of the CNG to a set pressure according to engine load; a differential pressure sensor that measures a differential pressure before and after the pressure adjustment valve; and a buffer tank that absorbs a variable pressure of the CNG in the main pipe. The discharge pressure of the LNG pump is controlled such that the differential pressure is increased when the pressure is low, and the differential pressure is decreased when the pressure is high.

The invention relates to a marine surface vessel (1), in particular a passenger ship, extending in a longitudinal direction between a bow (2) and a stern (3), comprising least one power providing apparatus (6) operatively connected to at least one propulsion unit (7) for propulsion of the vessel, a fuel tank arrangement (8) for storing gaseous fuel in a liquid phase, connected to the power providing apparatus (6) by means of a gas supply system for running the power providing apparatus (6), and a plurality of decks (91-98) distributed vertically, one above the other, the fuel tank arrangement (8) comprising two tank sub-arrangements (81, 82), each tank sub-arrangement comprising at least one gaseous fuel tank (811, 812, 821, 822), each fuel tank extending vertically past at least two of the decks (92-95), and at least two of the decks (92-95), past which the fuel tanks (811, 812, 821, 822) extend, each presents a passageway (941) extending between the tank sub-arrangements (81, 82).