The present invention relates to an intake system for natural gas engine. An intake system for an engine is provided. A conduit is configured to direct a combustible mixture to a cylinder head. A mixing unit is coupled to the conduit. The mixing unit includes a fuel doser configured to dispense fuel into the conduit and a first mixer positioned downstream of the fuel doser. The first mixer is configured to mix air and the fuel. The mixing unit further includes a exhaust gas doser configured to dispense exhaust gas into the conduit and a second mixer positioned downstream of the exhaust gas doser. The second mixer is configured to mix the exhaust gas with the air and the fuel to make the combustible mixture. An air intake throttle is configured to direct the air into the mixing unit.

The present invention relates to an intake system for natural gas engine. An intake system for an engine is provided. A conduit is configured to direct a combustible mixture to a cylinder head. A mixing unit is coupled to the conduit. The mixing unit includes a fuel doser configured to dispense fuel into the conduit and a first mixer positioned downstream of the fuel doser. The first mixer is configured to mix air and the fuel. The mixing unit further includes a exhaust gas doser configured to dispense exhaust gas into the conduit and a second mixer positioned downstream of the exhaust gas doser. The second mixer is configured to mix the exhaust gas with the air and the fuel to make the combustible mixture. An air intake throttle is configured to direct the air into the mixing unit.

Various methods and systems are provided for venting fuel lines in a dual-fuel engine. In one example, a method may include in response to an engine shut-down request, venting fuel lines to remove hydrogen from the fuel lines.

An internal combustion engine comprising: a main combustion chamber comprising at least one intake valve and at least one exhaust valve, wherein at least one intake port fluidically connected to an intake manifold is configured to supply an air and/or an air-fuel-mixture to the main combustion chamber via the at least one intake valve, and a pre-chamber which is in fluid connection with the main combustion chamber, wherein the pre-chamber is in fluid connection with the intake port and/or the intake manifold through a supply line, wherein at least one fuel injector is configured to enrich the air and/or air-fuel-mixture supplied to the main combustion chamber to have a lower ignition delay than an air-fuel-mixture supplied to the pre-chamber and/or air or air-fuel-mixture can be supplied to the pre-chamber to have a higher ignition delay than an air-fuel-mixture supplied to the main combustion chamber.

An internal combustion engine assembly is provided with a fuel tank for fuel including ethanol, and a reformer for steam reforming of ethanol that is with an outlet connected to a buffer tank. A first reformer supply duct extends from the fuel tank to the reformer via a fuel evaporator that is in heat exchanging contact with the exhaust gases, for supplying ethanol vapor to the reformer. A second reformer supply duct extends from a water reservoir to the reformer via a water evaporator that is in heat exchanging contact with the exhaust gases. The reformer is in heat exchanging contact with the catalytic converter and is adapted for reforming ethanol and water into syngas including carbon monoxide and hydrogen, and for supplying the syngas via the outlet to the buffer tank. The reformer and the catalytic converter may form an integrated unit.

A natural gas fueling system supplies methane gas to an engine and includes a filter assembly. The filter assembly includes a gas inlet configured to receive inlet gas and a methane permeable filter configured to separate methane gas and first contaminant gases from the inlet gas. The natural gas fueling system also includes a reformer apparatus configured to convert the first contaminant gases into a reformed gas stream including methane gas. The reformed gas is supplied to the gas inlet and is recirculated through the filter assembly to extract the methane gas from the reformed gas stream.

A remedial pollution control system for treating volatile organic compounds that may include a vapor concentrator connected to a line that is laden with volatile organic compounds, the concentrator has an organic condensate output line and a vapor output line; a mixing chamber adapted to receive air provided from an air supply line, combustible fuel from an alternate fuel supply line, and a vapor stream from the vapor output line to produce a mixed fuel supplied to an internal combustion engine, a control mixing system with a controller for producing a proper air to fuel ratio in the mixed fuel supply, and power generated to operate other devices used to more efficiently abate volatile organic compounds and reduce greenhouse gas emissions.

A gas injector for injecting a gaseous fuel, in particular directly into a combustion chamber of an internal combustion engine, including: a valve closing element for opening or closing a pass-through opening, a valve body, and a sealing seat between the valve body and the valve closing element, in the case of a maximum lift of the valve closing element a flow cross section between the valve body and the valve closing element being smaller in the flow direction upstream from the sealing seat than a flow cross section between the valve closing element and the sealing seat and being smaller than a flow cross section in the flow direction downstream from the sealing seat.

A method for operating an internal combustion engine including feeding a pilot quantity of gas fuel, into a prechamber before a piston reaches a top dead center position. The method comprises autoignition of the pilot quantity of gas fuel in the prechamber, feeding a main quantity of gas fuel into the prechamber after the autoignition, and ignition of the main quantity of gas fuel by the conditions in the prechamber that are brought about by the autoignited pilot quantity. The method makes it possible to operate an internal combustion engine purely with methane or some other gaseous fuel, by means of compression autoignition of the pilot quantity.

A method for precooling fuel delivery components of a machine having an engine fueled by a cryogenically-stored fuel is described. The fuel delivery components may be configured to operate at an operating temperature at or below a boiling point of the cryogenically-stored fuel. The method may comprise, in a vapor precooling mode, cooling the fuel delivery components to a temperature approaching the operating temperature with a vapor of the fuel taken from a reservoir cryogenically storing the fuel. The method may further comprise, in a liquid precooling mode, further cooling the fuel delivery components to the operating temperature with a liquid of the fuel taken from the reservoir.