Abstract: An internal combustion engine system is described herein. The system uses a mixer to mix two fuels to provide for a transition from using only one of the fuels to using only the other fuel as power demand changes. The output of the mixer is provided to the engine as a primary fuel. A controller opens and closes throttle valves to adjust the relative concentrations of a first fuel (e.g., diesel) and a second fuel (e.g., methanol) that enter the mixer. In some examples, rather than removing the desired performance and/or environmental benefits achieved by using the second fuel at power demand levels greater than the maximum achievable by only using the second fuel, the systems described herein allow the use of at least a portion of the second fuel in the primary fuel at those power demand levels.

Abstract: An internal combustion engine system is described herein. The system uses a mixer to mix two fuels to provide for a transition from using only one of the fuels to using only the other fuel as power demand changes. The output of the mixer is provided to the engine as a primary fuel. A controller opens and closes throttle valves to adjust the relative concentrations of a first fuel (e.g., diesel) and a second fuel (e.g., methanol) that enter the mixer. In some examples, rather than removing the desired performance and/or environmental benefits achieved by using the second fuel at power demand levels greater than the maximum achievable by only using the second fuel, the systems described herein allow the use of at least a portion of the second fuel in the primary fuel at those power demand levels.

Abstract: An internal combustion engine system is described herein. The system uses compressed air from a compressor to purge at least a portion of a fuel from an internal combustion engine. During a purge operation, a controller opens and closes an injector of the fuel to be purged to allow the compressed air from the compressor to push at least a portion of the fuel back into a fuel tank through the injector. The controller deenergizes a fuel pump that pumps the fuel to be purged, allowing the pressure of the fuel that is to be purged to reduce to a pressure that allows the compressed air to flow into the injector.

Abstract: An internal combustion engine system is described herein. The system uses compressed air from a compressor to purge at least a portion of a fuel from an internal combustion engine. During a purge operation, a controller opens and closes an injector of the fuel to be purged to allow the compressed air from the compressor to push at least a portion of the fuel back into a fuel tank through the injector. The controller deenergizes a fuel pump that pumps the fuel to be purged, allowing the pressure of the fuel that is to be purged to reduce to a pressure that allows the compressed air to flow into the injector.

Abstract: A fuel delivery system for an internal combustion engine system is described herein. The fuel delivery system uses one or more bidirectional purge components to provide for bidirectional purging of a fuel from at least a portion of the fuel delivery system. The bidirectional purge components provide for a fuel delivered using the fuel delivery system to be purged into the directional purge component in more than one fluid flow direction. When a differential pressure is applied across the bidirectional purge component, the fuel is purged into an inlet and an outlet of the bidirectional purge component, leaving the component through a purge outlet and into a tank. The differential pressure can be generated using a pressured fluid such as nitrogen or a pump downstream of the purge outlet.

Abstract: An internal combustion engine system is described herein. The internal combustion engine system uses one or more fuels that may be hydrophilic. The system uses a water measuring sensor to determine the concentration of water in the hydrophilic fuel. To meet power demands, the system uses the measured water concentration to modify data stored in a fuel map. The fuel map provides a controller the pump speeds and mixing ratio of the fuels for a given power level. The system receives that data and modifies it based on the measured concentration of water.

Abstract: A flow limiter and filter assembly for a fuel system of an engine includes a flow limiting valve attached to a filter element. The filter element has a large area inlet and a screen of small area outlets. Each of a plurality of quills for the fuel system includes a flow limiter and filter assembly positioned in a quill passage in contact with a limiter seat of a quill body, and the filter element is out of contact with the quill body.

Abstract: A passive hydraulically actuated non-electric shutdown pressure relief valve relieves pressure in the high pressure volume of a low static leak common rail fuel system after shutdown. When the common rail fuel system is in operation, a transfer pump provides medium pressure to hold the shutdown pressure relief valve closed. At shutdown, the residual medium pressure downstream from the transfer pump decays back to tank, and the residual high pressure trapped in the common rail and fuel injectors pushes open the shutdown pressure relief valve to release the high pressure after back to tank.

Abstract: A passive hydraulically actuated non-electric shutdown pressure relief valve relieves pressure in the high pressure volume of a low static leak common rail fuel system after shutdown. When the common rail fuel system is in operation, a transfer pump provides medium pressure to hold the shutdown pressure relief valve closed. At shutdown, the residual medium pressure downstream from the transfer pump decays back to tank, and the residual high pressure trapped in the common rail and fuel injectors pushes open the shutdown pressure relief valve to release the high pressure after back to tank.

Abstract: A common rail fuel system includes a reverse flow check valve fluidly positioned between each of a plurality of common rail fuel injectors and an outlet of a high pressure pump. The reverse flow check valves divide the overall system fluid volume into an upstream common volume and a plurality of separate downstream volumes. The upstream common volume is greater than the sum of the separate downstream volumes. The reverse flow check valve is movable between a first configuration with a large flow area and a second configuration with a small flow area. The reverse flow check valve associated with each of the individual fuel injectors may be housed in a quill that fluidly connects the fuel injectors to the high pressure common rail.