The various embodiments disclosed herein relate to systems and methods of improving fuel economy of internal combustion engines. In particular, the systems and methods relate to improving fuel economy of internal combustion engines by increasing the laminar flame speed (LFS) of fuel and hydrogen gas mixture. By increasing the laminar flame speed of the mixture, amount of carbon-based fuel that undergoes combustion increases. This may provide the advantage of minimizing overall fuel consumption by the engine, resulting in fuel savings. This may also provide the advantage of minimizing greenhouse gas emissions by the engine, resulting in environmental benefits.

A method of operating a vessel includes providing hydrogen or a fuel mixture containing hydrogen and a hydrocarbon fuel to a power generator disposed on the vessel, and providing power from the power generator to an electrical load of the vessel.

A power system includes an intake arrangement configured to intake charge air; a fuel arrangement configured to store a blend of methane (CH.sub.4) and hydrogen (H.sub.2) fuel; an engine configured to receive, ignite, and combust a mixture of the charge air and the blend of methane (CH.sub.4) and hydrogen (H.sub.2) fuel; and a controller coupled to selectively command such that, in a first mode, the controller commands the one or more of the intake arrangement, the fuel arrangement, and the engine such that the charge air and the blend of methane (CH.sub.4) and hydrogen (H.sub.2) fuel are introduced at a stoichiometric equivalence ratio; and in a second mode, the controller commands the one or more of the intake arrangement, the fuel arrangement, and the engine such that the charge and the blend of methane (CH.sub.4) and hydrogen (H.sub.2) fuel are introduced at a lean equivalence ratio.

The performance of an automotive gasoline fueled spark-ignited internal combustion engine (ICE) optionally operated with a dedicated exhaust gas recycle system is enhanced by reforming the fuel in the presence of injected water to increase the yield of hydrogen which permits higher compression ratios and suppresses engine knock associated with pre-ignition of the fuel. Reforming can occur (a) in the cylinder with the reaction of a fuel-rich mixture and steam from the water injected into the intake manifold of one or more dedicated exhaust gas recirculation cylinders; (b) in a catalytic reformer located upstream of the engine; (c) in a catalytic reformer located downstream of the engine that receives fuel and the exhaust gas stream from the dedicated exhaust gas recirculation cylinder(s), and returns cooled reformate to the intake manifold; and (d) in a catalytic reformer that receives fuel and the exhaust gas stream from the engine exhaust gas manifold, and delivers reformate to the intake manifold.

An engine/reformer system accepts a first fuel and reforms it into syngas for use as a fuel in an accompanying internal combustion engine. Prior to reforming, the first fuel is pressurized and/or heated to at or near supercritical fluid conditions, such that the resulting syngas leaves the reformer in a supercritical fluid state. Injection of the supercritical syngas into an engine cylinder avoids the autoignition problems that occur when gaseous syngas is used. The first fuel is a fully self-reforming fuel (one that needs no separate water supply for complete conversion to syngas), and can beneficially be a “wet” fuel, such as ethanol containing water, allowing the system to use intermediate products of an ethanol production process (such as hydrous ethanol and stillage wastewater) as fuel, and reducing the overall cost of fuel production and engine operation.

An internal combustion engine in which a fuel reforming operation in a fuel reformation cylinder is not executed when a gas temperature of a fuel reformation chamber at a time point when a piston in the fuel reformation cylinder reaches a compression top dead point is estimated to fall short of a reforming operation allowable lower limit gas temperature set based on a lower limit value of a reforming reaction enabling temperature. For example, fuel is supplied from an injector so that an equivalence ratio in the fuel reformation chamber is less than 1. Alternatively, the fuel supply from an injector is stopped. This way, a supply of non-reformed fuel from the fuel reformation cylinder to an output cylinder can be avoided, and knocking in the output cylinder can be avoided.

The present invention relates to a zero emission propulsion system and generator sets using ammonia (NH.sub.3) as fuel for engines and power plants such as steam boilers (5) for steam turbines (7), piston engines (9), fuel cells (10) or Stirling engines (11). Due to the poor flammability of ammonia (NH.sub.3), a hydrogen reactor (4) can split ammonia (NH.sub.3) into hydrogen (H.sub.2) and nitrogen (N.sub.2). The hydrogen (H.sub.2) can be placed in a hydrogen tank (8) for intermediate storage and the nitrogen can be stored in a nitrogen tank (6). The hydrogen (H.sub.2) could be mixed with ammonia (NH.sub.3) to improve flammability and thus facilitate the ignition of an air/ammonia (NH.sub.3) mixture in engines or power plants (5, 9, 11). Alternatively, hydrogen (¾) may be supplied in a separate fuel system (5-1, 9-5, 11-8) as a pilot fuel for pilot ignition of an air/ammonia (NH3) mixture. The hydrogen (H.sub.2) can also be used in AIP systems along with oxygen (O2) from an oxygen tank (22). The hydrogen (H.sub.2) will then be used for fuel cells (10), for combustion in a steam turbine inlet/high pressure side (7-1), or in a Stirling engine (11). In addition to hydrogen (H.sub.2), other bio and fossil fuels from the fuel tank (12) can be used as pilot fuel for pilot ignition of an air/ammonia (NH.sub.3) mixture. The advantage of using existing bio or fossil fuels for pilot ignition is that engines or power plants (5, 9, 11) will have a pilot fuel system with sufficient capacity to maintain normal operations if ammonia (NH.sub.3) is not available. Alternatively, that engines or power plants (5, 9, 11) have an additional fuel system for existing bio or fossil fuels in order to maintain normal operations if ammonia (NH.sub.3) is not available. The nitrogen (N.sub.2) in the nitrogen tank (6) can be used as a gas in fire extinguishing systems or for submarine ballast tank blows.

A ship propulsion system comprises at least one internal combustion engine with a combustion chamber for burning a fuel and a turbocharger with a compressor in an intake tract of the internal combustion engine. The ship propulsion system further comprises an electrolysis device, which produces hydrogen and oxygen gas, which are added on a pressure side of the compressor and conducted to the internal combustion engine. Moreover, a water tank and an alcohol tank are connected to a pressure side of the compressor in order to add water and alcohol to the charge air.

The invention concerns a method of control of NOx emission from an internal combustion engine fueled with a mixture of a hydrocarbon fuel and hydrogen. The method comprises reducing the hydrogen content of the fuel mixture at high engine loads.

This invention provides means and a method to eliminate emissions from an internal combustion engine during cold-starts and warm-starts. An oxidizer intake valve external to the engine head and an exhaust valve following the after-treatment system and condensing heat exchanger are closed, thus sealing all gasses inside the engine and the exhaust after-treatment system before starting the engine. Oxygen and hydrogen are used as the oxidizer and fuel to start this engine and operate this engine until the exhaust after-treatment systems have reached their required operating temperatures. This emissions-free startup system works equally well on two, four, six, or eight stroke engines, one or multiple cylinder engines, and spark or compression ignition engines. This invention also provides a means and method to clean the interior of an engine and the after-treatment systems of soot, particulate, and the catalytic surfaces without disassembling the engine or the after-treatment systems.