In a combustion cycle in which fuel for forming a homogenized air-fuel mixture in the combustion chamber is injected from the first fuel injector, ignition-use fuel for forming an ignition-use air-fuel mixture in the vicinity of the electrode part is injected from the second fuel injector, and lean combustion is performed by an excess air rate of 2.0 or more, the ignition-use fuel is injected by at least an injection rate of 1.0 mm.sup.3/ms or more for a duration of 250 μs or more in an interval from a crank angle advanced by exactly 20 degrees from an ignition timing of the spark plug to the ignition timing, and the quantity of the ignition-use fuel is 2.0 mm.sup.3/st or less.

A system for supplying hydrogen gas to an engine is disclosed. The system includes a main line configured to send hydrogen gas produced in a hydrogen gas producer by electrolysis to a supply line; a sub-line configured to send hydrogen gas from a hydrogen absorbing alloy cylinder to the main line, a governor configured to maintain an engine rotation speed within certain range; and a control device. The governor sends a signal corresponding to the engine rotation speed to the control device. A pressure regulating valve is disposed in the sub-line to be downstream with respect to the hydrogen absorbing alloy cylinder to regulate a supply amount of added hydrogen. An opening degree of the valve is adjusted based on a signal from the control device corresponding to the opening degree of the valve for supplying the added hydrogen with an amount according to a load state of the engine.

A housing defines a gaseous fuel inlet and a gaseous fuel outlet. A rotor defines an internal flow passage therethrough that rotates with the rotor to, alternately, allow gaseous fuel flow, or to block gaseous fuel flow, between the inlet and the outlet, based on a position of the rotor. A seal is biased to abut an exterior surface of the rotor. The seal is between the rotor and the outlet. An actuator is rotably coupled to the rotor. The driver is configured to rotate the rotor. A controller is in communication with the driver and is configured to control the driver to rotate at a rate based on an engine speed of the engine.

A supplemental fuel system includes a fuel mixer. The fuel mixer includes a nozzle and a stem. The nozzle is configured to be positioned within a conduit of an air supply system for a compression-ignition engine. The nozzle has a body defining a first inlet positioned at a first nozzle end thereof, an outlet positioned at a second nozzle end thereof, a second inlet positioned between the first nozzle end and the second nozzle end, and a nozzle passage extending from the first nozzle end to the second nozzle end that is configured to receive air flowing through the conduit. The stem has a first stem end interfacing with the second inlet. The stem is configured to extend through a wall of the conduit such that a second stem end is positioned outside of the conduit.

An engine operable in a premixed combustion system and a diffusion combustion system. The engine includes a main fuel injection valve, a pilot fuel injection valve, a liquid fuel tank, a main fuel supply path, a pilot fuel supply path, a pilot fuel filter, a pilot fuel high-pressure pump, a pilot fuel tank, and a pilot fuel supply pump. The pilot fuel tank stores pilot fuel sent from the pilot fuel high-pressure pump and not injected by the pilot fuel injection valve. This pilot fuel is sent to an automatic backwash filter and a pilot fuel filter while not passing through the liquid fuel tank.

An engine operable in a premixed combustion system and a diffusion combustion system. The engine includes a main fuel injection valve, a pilot fuel injection valve, a liquid fuel tank, a main fuel supply path, a pilot fuel supply path, a pilot fuel filter, a pilot fuel high-pressure pump, a pilot fuel tank, and a pilot fuel supply pump. The pilot fuel tank stores pilot fuel sent from the pilot fuel high-pressure pump and not injected by the pilot fuel injection valve. This pilot fuel is sent to an automatic backwash filter and a pilot fuel filter while not passing through the liquid fuel tank.

Systems and methods for supplying primary fuel and secondary fuel to an internal combustion engine may include supplying a first amount of the primary fuel and a second amount of the secondary fuel to the internal combustion engine. The system may include a first manifold to provide primary fuel to the internal combustion engine, and a primary valve associated with the first manifold to provide fluid flow between a primary fuel source and the internal combustion engine. A second manifold may provide secondary fuel to the internal combustion engine, and a fuel pump and/or a secondary valve may provide fluid flow between a secondary fuel source and the internal combustion engine. A controller may determine a total power load, the first amount of primary fuel, and the second amount of secondary fuel to supply to the internal combustion engine to meet the total power load.

Disclosed herein are a fuel supply system for ships and a fuel supply method using the same. The fuel supply method includes: 1) supplying an excess amount of liquefied gas as fuel to an incompressible fluid-fueled engine (E); 2) cooling unconsumed fuel discharged from the engine (E) through heat exchange with liquefied gas discharged from a storage tank (T); 3) returning the unconsumed fuel discharged from the engine (E) and having been cooled through heat exchange in step 2) to the storage tank (T); and 4) supplying the liquefied gas discharged from the storage tank (T) and having been used as refrigerant for heat exchange in step 2) to the engine (E). The fuel supply method can prevent cavitation in the engine (E) by supplying the excess amount of liquefied gas sufficient to accommodate variation in load of the engine (E) as fuel to the engine (E).

A gas fuel supply system for supplying the gas fuel via an opening of an intake supply pipe that is connected to a combustion chamber in an engine operable in each of a gas fuel combustion mode and an oil fuel combustion mode includes: the gas fuel supply valve for regulating an amount of the gas fuel, the gas fuel supply valve having plural gas supply holes, from which the gas fuel is fed in a direction toward the opening when the valve is opened; and an opening regulation valve provided between the gas fuel supply valve and the opening and having an opening hole, an opening area of which can be regulated. The gas fuel supply system is configured that extended axes of all the gas supply holes pass through the fully opened opening hole.

Systems and methods for supplying primary fuel and secondary fuel to an internal combustion engine may include supplying a first amount of the primary fuel and a second amount of the secondary fuel to the internal combustion engine. The system may include a first manifold to provide primary fuel to the internal combustion engine, and a primary valve associated with the first manifold to provide fluid flow between a primary fuel source and the internal combustion engine. A second manifold may provide secondary fuel to the internal combustion engine, and a fuel pump and/or a secondary valve may provide fluid flow between a secondary fuel source and the internal combustion engine. A controller may determine a total power load, the first amount of primary fuel, and the second amount of secondary fuel to supply to the internal combustion engine to meet the total power load.