Disclosed is an efficient recycling system for exhaust energy of an internal combustion engine. Firstly, a thermoelectric generation device recycles high-temperature waste heat energy in the exhaust of the internal combustion engine and recycles high-temperature heat that originally radiates into the ambient atmosphere on the surface of the volute (24). Secondly, pressure energy in the exhaust of the internal combustion engine is efficiently recycled by using a turbocharging device, and the efficiency of the turbocharging device is improved through the graphite sealing device. Finally, low-temperature waste heat energy in the exhaust of the internal combustion engine is efficiently recycled by using an organic Rankine cycle device. The risk of decomposition caused by the fact that the working medium used by organic Rankine cycle works in a high-temperature environment is avoided, thereby ensuring the cycle efficiency and the working reliability of the organic Rankine cycle.

The disclosure concerns a waste heat recovery system that is configured to operate as a prime mover in emergency case, when the heat source is down. The waste heat recovery system comprises, in addition to a heater configured to circulate a working fluid in heat exchange relationship with a heating fluid from the heat source to heat the working fluid, an independent auxiliary heat source configured to provide an additional heating fluid in heat exchange relationship with the working fluid, to heat the working fluid. The system is provided with a secondary heater, which is configured to circulate the working fluid in heat exchange relationship with the additional heating fluid from the independent auxiliary heat source and which can be used to replace the heater or in combination with the heater.

The disclosure concerns a waste heat recovery system that is configured to operate as a prime mover in emergency case, when the heat source is down. The waste heat recovery system comprises, in addition to a heater configured to circulate a working fluid in heat exchange relationship with a heating fluid from the heat source to heat the working fluid, an independent auxiliary heat source configured to provide an additional heating fluid in heat exchange relationship with the working fluid, to heat the working fluid. The system is provided with a secondary heater, which is configured to circulate the working fluid in heat exchange relationship with the additional heating fluid from the independent auxiliary heat source and which can be used to replace the heater or in combination with the heater.

An exhaust gas heat recovery system for an internal combustion engine has a pump for conveying an operating fluid, an evaporator for converting the operating fluid from the liquid state to the gaseous state, and a condenser for liquefaction of the operating fluid, and having an expansion engine through which the gaseous operating fluid can flow. A sensor is arranged on the expansion engine with which a function of the expansion engine can be monitored. An exhaust system may have such an exhaust gas heat recovery system, and a method for the diagnosis of such an exhaust heat recovery system.

An exhaust gas heat recovery system for an internal combustion engine has a pump for conveying an operating fluid, an evaporator for converting the operating fluid from the liquid state to the gaseous state, and a condenser for liquefaction of the operating fluid, and having an expansion engine through which the gaseous operating fluid can flow. A sensor is arranged on the expansion engine with which a function of the expansion engine can be monitored. An exhaust system may have such an exhaust gas heat recovery system, and a method for the diagnosis of such an exhaust heat recovery system.

The present invention relates to a control unit for a waste heat recovery system, wherein the waste heat recovery system is operated in a first mode of operation after a first condition is fulfilled and the system is operated in a second mode of operation after a second condition is fulfilled. The invention also relates to a method for starting an expansion device in a waste heat recovery system.

The present invention relates to a control unit for a waste heat recovery system, wherein the waste heat recovery system is operated in a first mode of operation after a first condition is fulfilled and the system is operated in a second mode of operation after a second condition is fulfilled. The invention also relates to a method for starting an expansion device in a waste heat recovery system.

A heat accumulation and dissipation device (1) for an internal combustion engine (2) includes, in a cooling circuit (3) for circulating cooling water used to cool the internal combustion engine (2), a heat accumulator (7) for accumulating the cooling water, and an exhaust heat recovery device (9) for recovering the heat of exhaust gas through the cooling water, wherein when the internal combustion engine (2) is started, heat is dissipated by sending the cooling water of the heat accumulator (7) to the internal combustion engine (2). The cooling circuit (3) includes a heat accumulation and dissipation circuit (8) configured to perform heat accumulation and dissipation while circulating the cooling water between the internal combustion engine (2) and the heat accumulator (7), and the heat accumulator (9) is arranged upstream of the heat accumulator (7) of the heat accumulation and dissipation circuit (8).

Aircraft power plants including combustion engines, and associated methods for recuperating waste heat from such aircraft power plants are described. A method includes transferring the heat rejected by the internal combustion engine to supercritical CO.sub.2 (sCO.sub.2) used as a working fluid in a heat engine. The heat engine converts at least some the heat transferred to the sCO.sub.2 to mechanical energy to perform useful work onboard the aircraft.

Aircraft power plants including combustion engines, and associated methods for recuperating waste heat from such aircraft power plants are described. A method includes transferring the heat rejected by the internal combustion engine to supercritical CO.sub.2 (sCO.sub.2) used as a working fluid in a heat engine. The heat engine converts at least some the heat transferred to the sCO.sub.2 to mechanical energy to perform useful work onboard the aircraft.