An engine system includes an engine configured to combust liquid natural gas and generate an exhaust gas comprising methane; a catalytic reactor coupled downstream of the engine and configured to convert methane into a product through one or more of oxidative coupling of methane (OCM) reaction and steam methane reforming (SMR) reaction; and a recirculation loop configured to recirculate at least a part of the product back to the engine.

A pump includes a reservoir configured to receive a fluid pressurized by a boost pump. The pump also includes at least one pumping mechanism configured to receive a first flow of fluid from the reservoir and direct the first flow of fluid into a discharge passage of the pump without pumping the first flow of fluid when priming the pump. The at least one pumping mechanism is disposed in the reservoir such that the fluid in the reservoir surrounds at least a portion of the at least one pumping mechanism. The discharge passage is configured to output the first flow of fluid from the pump. The pump further includes a bypass passage configured to communicate a second flow of fluid from the reservoir to the storage tank.

Aspects relate to zero-emission propulsion systems and generators using ammonia (NH.sub.3) as fuel for engines and power plants. While ammonia has poor flammability, mixing hydrogen with ammonia (NH.sub.3) may improve flammability and thus facilitate the ignition of an air/ammonia mixture in engines or power plants. Alternatively, hydrogen (H.sub.2) may be supplied in a separate fuel system as a pilot fuel for pilot ignition of an air/ammonia mixture. Hydrogen can also be used in air independent systems along with oxygen (O.sub.2) from an oxygen tank. In addition to hydrogen, other bio or fossil fuels can be used as pilot fuel for pilot ignition of an air/ammonia mixture. An advantage of using existing bio or fossil fuels for pilot ignition is that engines or power plants will have a pilot fuel system with sufficient capacity to maintain normal operations if ammonia is not available.

A system for measuring quality of fuel in an engine is disclosed. The system includes a fuel quality measuring unit and a controller in communication with the fuel quality measuring unit. The fuel quality measuring unit includes a first valve, a second valve, and a quality measurement sensor disposed between the first valve and the second valve. The controller is configured to determine whether the engine is running in a steady state condition, and identify a measurement window based on a pressure of the fuel at an inlet, an Intake Manifold Pressure (IMP), and the steady state condition. The controller is configured to control an opening and a closing of the first valve, the second valve, and a fuel metering valve during the measurement window. The controller is configured to determine the quality of the fuel captured between the first valve and the second valve by the quality measurement sensor.

A method of operating an internal combustion engine comprising a cylinder and a piston, the method including injecting into the cylinder, as a liquid, a fuel which has been condensed into its liquid phase via a refrigeration process, such that the fuel vaporises into its gaseous phase during a compression stroke of the piston and before combustion such that a rise in temperature caused by the compression stroke is limited by the absorption of heat by the fuel.

A port injection system for gaseous fuels may include an injector body defining a hydraulic fluid inlet chamber, a hydraulic fluid exit passageway, a hydraulic fluid actuation passageway, a check valve inlet passageway fluidly connected with the hydraulic fluid actuation passageway, a valve chamber, and a gaseous fuel inlet chamber. An electrical solenoid actuator may be mounted to the injector body, with the electrical solenoid actuator including a movable armature, and a poppet valve connected to the movable armature and disposed within the valve chamber. The poppet valve may be movable between a pressurized hydraulic fluid flow blocking position and a pressurized hydraulic fluid flow passing position. A check valve may be disposed within the check valve inlet passageway. A gas admission valve may be disposed at least partially within the gaseous fuel inlet chamber and in contact with the check valve such that movement of the check valve by hydraulic fluid entering the check valve inlet passageway results in actuation of the gas admission valve away from a normally closed position closing off the gaseous fuel inlet chamber to a fuel injection position wherein gaseous fuel is allowed to flow from the gaseous fuel inlet chamber into an intake manifold or intake port of an engine on which the injector body is mounted.

A system is provided. The system includes a fuel receiving module configured for being installed within a marine vehicle, the fuel receiving module including at least a fuel receptacle. A tank module for storing gaseous fuel is provided. The tank module is in communication with the fuel receiving module. A pressure reduction module is configured for reducing a pressure of the gaseous fuel from the tank module to a pressure suitable for an engine of the marine vehicle. An engine module is in communication with an engine control module for controlling operation of the engine. A helm control module is in communication with the engine module and at least one other module for controlling operation of the system.

A system for exchanging of different fuels that can be used for operation of an engine. The system includes a fuel exchange unit, a control and an exchange return conduit. The fuel exchange unit is configured to deliver a first fuel at pressure into the injections system given a switched-off engine, in order to replace a second fuel, which is located in the injection system, with the first fuel. A fuel delivery system includes a media converter which includes a deflectable element. The media converter is driven by a drive unit via the fluid by way of the fluid being able to be led at a varying pressure to the media transformer via a first feed conduit, and is configured to deliver the fuel via a pumping effect.

An apparatus and method for igniting a gaseous fuel directly introduced into a combustion chamber of an internal combustion engine comprises steps of heating a space near a fuel injector nozzle; introducing a pilot amount of the gaseous fuel in the combustion chamber during a first stage injection event; controlling residency of the pilot amount in the space such that a temperature of the pilot amount increases to an auto-ignition temperature of the gaseous fuel whereby ignition occurs; introducing a main amount of the gaseous fuel during a second stage injection event after the first stage injection event; and using heat from combustion of the pilot amount to ignite the main amount.

A technique for providing electric power to an electric power utility grid includes driving an electric power alternator coupled to the grid with a spark-ignited or direct injection internal combustion engine; detecting a change in electrical loading of the alternator; in response to the change, adjusting parameters of the engine and/or generator to adjust power provided by the engine. In one further forms of this technique, the adjusting of parameters for the engine includes retarding spark timing and/or interrupting the spark ignition; reducing or retarding direct injection timing or fuel amount and/or interrupting the direct injection; and/or the adjusting of parameters for the generator including increasing the field of the alternator or adding an electrical load.