A method for operating an exhaust gas burner that is situated in an exhaust gas system downstream from an internal combustion engine of a motor vehicle during a start phase of the exhaust gas burner, in which the internal combustion engine is not fired. The method includes an incremental increasing of the air mass flow supplied to the exhaust gas burner and an incremental varying of a fuel mass flow supplied to the exhaust gas burner.

An exhaust gas system is provided for a transport refrigeration unit (TRU) engine. The exhaust gas system includes an exhaust system. The exhaust system includes a catalyst operable in a temperature range to catalyze exhaust gas produced in the TRU engine and flown through the exhaust system. The exhaust gas system further includes temperature sensors respectively disposed to sense exhaust gas temperatures upstream of and downstream from the catalyst, at least one of first, second and third valves which are proportionally controllable to moderate amounts of air provided to the TRU engine, fuel provided to the TRU engine and air provided to the catalyst, respectively, and a controller. The controller is configured to compare sensed exhaust gas temperatures with the temperature range and issue a proportional signal to the at least one of the first, second and third valves in accordance with results of the comparison.

The invention relates to a method involving the treatment of the pollutants emitted by a vehicle having a heat engine, in which catalyst means (3) are heated, characterised in that the amount of oxygen (OS) in the catalyst means (3) is controlled to be over a minimum amount of oxygen (OS1) by injecting air upstream of said catalyst means (3).

The invention relates to a method involving the treatment of the pollutants emitted by a vehicle having a heat engine, in which catalyst means (3) are heated, characterised in that the amount of oxygen (OS) in the catalyst means (3) is controlled to be over a minimum amount of oxygen (OS1) by injecting air upstream of said catalyst means (3).

An engine assembly and a method of control thereof is provided. The engine assembly comprises: an exhaust gas aftertreatment device having an inlet for receiving exhaust gases leaving an engine; a heater for selectively heating gases at or upstream of the exhaust gas aftertreatment device; an air moving device for driving a flow of gases into the inlet of the exhaust gas aftertreatment device when the engine is in a non-running condition; and a controller configured to, prior to the engine being started: operate the heater to heat gases at or upstream of the inlet; and operate the air moving device to drive a flow of gases into the inlet to thereby heat the exhaust gas treatment device.

An engine assembly and a method of control thereof is provided. The engine assembly comprises: an exhaust gas aftertreatment device having an inlet for receiving exhaust gases leaving an engine; a heater for selectively heating gases at or upstream of the exhaust gas aftertreatment device; an air moving device for driving a flow of gases into the inlet of the exhaust gas aftertreatment device when the engine is in a non-running condition; and a controller configured to, prior to the engine being started: operate the heater to heat gases at or upstream of the inlet; and operate the air moving device to drive a flow of gases into the inlet to thereby heat the exhaust gas treatment device.

Methods and systems are provided for expediting exhaust catalyst light-off prior to an anticipated engine cold-start event. In one example, a method may include, in anticipation of an engine cold-start, preemptively operating an electric booster and routing compressed air to the catalyst to increase a temperature of the exhaust catalyst while maintaining the engine inactive.

Engine systems use a three-way catalyst followed by air injection and mixing to convert all hydrocarbons and carbon monoxide under various load conditions when exhaust gas temperature is above 500 degrees Celsius. A three-way catalytic converter is disposed in the exhaust system. A nozzle is configured to inject air into the exhaust system downstream from the three-way catalytic converter. A mixing plate with or without catalyst coatings is disposed in the exhaust system downstream from the nozzle. The mixing plate is bow shaped with a concave shaped side facing the nozzle to enhance carbon monoxide conversion. Optional two way catalytic converters are added downstream from the mixing plate to further reduce tailpipe hydrocarbon and carbon monoxide emissions.

An engine system includes an internal combustion engine having an engine block with one or more piston-cylinder arrangements communicating with an intake manifold and an exhaust manifold, a charge air passageway to the intake manifold, and an exhaust gas passageway that receives exhaust gas from the exhaust manifold. The engine system also includes one or more turbochargers each including a compressor to compress charge air and output the compressed charge air to the charge air passageway and a turbine that receives exhaust gas from the exhaust gas passageway and drives the compressor in response to the exhaust gas passing through the turbine. An air pump is positioned downstream of the compressor that supplies a portion of the compressed charge air into the exhaust gas passageway upstream of the turbine, such that the turbine receives both exhaust gas and compressed charge air.

An engine system includes an internal combustion engine having an engine block with one or more piston-cylinder arrangements communicating with an intake manifold and an exhaust manifold, a charge air passageway to the intake manifold, and an exhaust gas passageway that receives exhaust gas from the exhaust manifold. The engine system also includes one or more turbochargers each including a compressor to compress charge air and output the compressed charge air to the charge air passageway and a turbine that receives exhaust gas from the exhaust gas passageway and drives the compressor in response to the exhaust gas passing through the turbine. An air pump is positioned downstream of the compressor that supplies a portion of the compressed charge air into the exhaust gas passageway upstream of the turbine, such that the turbine receives both exhaust gas and compressed charge air.