A two-stage combustor having as constituent parts: a partial oxidation reactor, which catalytically converts a hydrocarbon fuel and a first supply of oxidant into a gaseous partial oxidation product; and a deep oxidation reactor having a premixer plenum fluidly connected to a porous heat spreader, which converts the gaseous partial oxidation product to deep oxidation products. In one embodiment, the premixer plenum provides an empty space wherein combustion occurs in flame mode. In a second embodiment, the premixer plenum contains a high pore density foam matrix, absent catalyst, which facilitates holding a flameless combustion downstream within the porous heat spreader. In both embodiments heat produced during combustion is transmitted from the heat spreader to an associated heat acceptor, such as a heater head of a Stirling engine.

A two-stage combustor having as constituent parts: a partial oxidation reactor, which catalytically converts a hydrocarbon fuel and a first supply of oxidant into a gaseous partial oxidation product; and a deep oxidation reactor having a premixer plenum fluidly connected to a porous heat spreader, which converts the gaseous partial oxidation product to deep oxidation products. In one embodiment, the premixer plenum provides an empty space wherein combustion occurs in flame mode. In a second embodiment, the premixer plenum contains a high pore density foam matrix, absent catalyst, which facilitates holding a flameless combustion downstream within the porous heat spreader. In both embodiments heat produced during combustion is transmitted from the heat spreader to an associated heat acceptor, such as a heater head of a Stirling engine.

A method for controlling an internal combustion engine system, the engine system including a combustor arranged to receive air and fuel, and combust the received air and fuel, an expander arranged to expand exhaust gases from the combustion in the combustor and to extract energy from the expanded exhaust gases, and a communication valve arranged to control a communication between the combustor and the expander, including determining during operation of the engine system whether there is a pressure difference across said communication valve.

A method for controlling an internal combustion engine system, the engine system including a combustor arranged to receive air and fuel, and combust the received air and fuel, an expander arranged to expand exhaust gases from the combustion in the combustor and to extract energy from the expanded exhaust gases, and a communication valve arranged to control a communication between the combustor and the expander, including determining during operation of the engine system whether there is a pressure difference across said communication valve.

The regenerative cooling system (100) is provided for a regenerative heat engine (1) and comprises a cooling chamber (79) which surrounds a gas expander (78), leaving open a gas circulation space (80) between said chamber (79) and said expander (78), a working gas (81) expelled from the gas expander (78) circulating in said space (80) before returning to a regenerative heat exchanger (5) where it is cooled, a large portion of the heat of said gas (81) being reintroduced into the thermodynamic cycle of the regenerative heat engine (1).

The regenerative cooling system (100) is provided for a regenerative heat engine (1) and comprises a cooling chamber (79) which surrounds a gas expander (78), leaving open a gas circulation space (80) between said chamber (79) and said expander (78), a working gas (81) expelled from the gas expander (78) circulating in said space (80) before returning to a regenerative heat exchanger (5) where it is cooled, a large portion of the heat of said gas (81) being reintroduced into the thermodynamic cycle of the regenerative heat engine (1).

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 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.

A method for controlling an internal combustion engine system, the engine system including a combustor arranged to receive air and fuel, and combust the received air and fuel, an expander arranged to expand exhaust gases from the combustion in the combustor and to extract energy from the expanded exhaust gases, and a communication valve arranged to control a communication between the combustor and the expander, including determining during operation of the engine system whether there is a pressure difference across said communication valve.

A method for controlling an internal combustion engine system, the engine system including a combustor arranged to receive air and fuel, and combust the received air and fuel, an expander arranged to expand exhaust gases from the combustion in the combustor and to extract energy from the expanded exhaust gases, and a communication valve arranged to control a communication between the combustor and the expander, including determining during operation of the engine system whether there is a pressure difference across said communication valve.