The engines include compression cylinders, combustion cylinders, an air rail, and a heat exchanger. The methods of operating a compression ignition engine include taking air into a compression cylinder of the engine, compressing the air in the compression cylinder to raise the pressure and temperature of the air, passing the compressed air through a heat exchanger, and from the heat exchanger into a combustion cylinder, further compressing the compressed air during a compression stroke of the combustion cylinder, igniting fuel in the combustion cylinder at or near the end of the compression stroke by compression ignition, followed by a power stroke, and opening an exhaust valve at the end of the power stroke and passing at least some of the exhaust in the combustion cylinder through the heat exchanger to heat air that has been compressed in the compression cylinder and is then passing through the heat exchanger.

The disclosure relates to a method for operating a supercharged internal combustion engine having at least one cylinder group with a number n of combustion chambers, wherein, during a first operating state, all n combustion chambers are supplied with combustion air via a primary charge air path and, during a second operating state, only a portion of the n combustion chambers are supplied with combustion air from the primary charge air path and another portion of the n combustion chambers are supplied with combustion air from a separate compressed air reservoir.

A method for cold start pre-warming of a pressure-charged internal combustion engine and/or of an exhaust gas aftertreatment device of a internal combustion engine, includes arranging a cold-starting aid in the intake duct for warming the charge air while the engine is stationary. The internal combustion engine has at least one working cylinder with at least one inlet valve and at least one outlet valve and further includes a device for setting a valve position. The internal combustion engine can be pressure-charged by a pressure-charging device operable by an electric motor. In the method, after detection of a cold start of the internal combustion engine: the cold-starting aid is activated while the engine is stationary; electric-motor operation of the pressure-charging device is activated; and a valve overlap between at least one inlet valve and at least one outlet valve is set.

A method for warming an aftertreatment system of an engine system while an engine of the engine system is not running comprising starting at least one of an electric compressor and an electric heater using stored electrical energy and passing air through the engine system to at least a portion of the aftertreatment system when the engine of the engine system is not running.

A method for warming an aftertreatment system of an engine system while an engine of the engine system is not running comprising starting at least one of an electric compressor and an electric heater using stored electrical energy and passing air through the engine system to at least a portion of the aftertreatment system when the engine of the engine system is not running.

A method for warming an aftertreatment system of an engine system while an engine of the engine system is not running comprising starting at least one of an electric compressor and an electric heater using stored electrical energy and passing air through the engine system to at least a portion of the aftertreatment system when the engine of the engine system is not running.

An internal combustion engine system includes a compressor arranged to compress air, at least one combustor, at least one of the at least one combustor being arranged to receive the compressed air, and an exhaust treatment device arranged to process exhaust gases produced by at least one of the at least one combustor, a heat exchanger arranged to receive the compressed air from the compressor before it reaches the at least one of the at least one combustor, and wherein the heat exchanger is arranged to transfer heat from the compressed air to the exhaust treatment device.

An enhanced pressure-wave supercharger for a combustion engine utilizes a superior pressure wave process cycle design. The design utilizes a select final portion of the compressed gas stream exiting the rotor, and supplies it to a subsequent inlet port ahead of and prior to the introduction into the rotor of the aspirated air to be compressed. Work is extracted within the rotor from this gas stream and transferred into rotational energy of the rotor through using a portion the available momentum of the compressed gas via incidence on the rotor webs to turn the rotor by means of conventional turbomachinery principles.

An internal combustion engine system includes at least one combustor, a compressor arranged to compress air, an air guide arranged to guide compressed air from the compressor to at least one of the at least one combustor, an expander arranged to expand exhaust gases from at least one of the at least one combustor and to extract energy from the expanded exhaust gases, and an exhaust guide arranged to guide exhaust gases from at least one of the at least one combustor to the expander, wherein the exhaust guide is at least partly integrated with the air guide.

An internal combustion engine system includes a compressor arranged to compress air, at least one combustor, at least one of the at least one combustor being arranged to receive the compressed air, and an exhaust treatment device arranged to process exhaust gases produced by at least one of the at least one combustor, a heat exchanger arranged to receive the compressed air from the compressor before it reaches the at least one of the at least one combustor, and wherein the heat exchanger is arranged to transfer heat from the compressed air to the exhaust treatment device.