A device for utilizing waste heat from an engine, which is provided with a Rankine cycle device having an expander bypass passage and a bypass valve that opens and closes the expander bypass passage, and transmits the output torque Tr of the Rankine cycle device to the engine, estimates the output torque Tr of the Rankine cycle device accurately. An output calculation part includes a torque estimation portion that estimates the torque of an expander. The torque estimation portion has a first torque estimation equation corresponding to an opening position of a bypass valve, and a second torque estimation equation corresponding to a closed position of the bypass valve. The output calculation part calculates an output torque Tr of a Rankine cycle device, based on a torque estimated value by the first or second torque estimation equation.

A parallel motion heat energy power machine and a working method thereof, includes a heat collector, an insulating pipe, a gasification reactor, an atomizer, a cylinder, a piston, a piston ring, an automatic exhaust valve, a cooler, a liquid storage tank, a pressure pump, a push-pull rod, an insulating layer, and a housing. The two cylinders are oppositely arranged on the housing in parallel. The piston is arranged inside the cylinder. The piston is provided with the piston ring. The pistons are arranged on both ends of the push-pull rod. The heat collector is connected to the gasification reactor through the insulating pipe. The atomizer is arranged on the air inlet end of the gasification reactor. The parallel motion heat energy power machine and working method thereof has a high heat-energy conversion efficiency. It is energy-saving, environmentally friendly, and less noisy.

A system for recovering thermal energy from one or more devices of an engine is provided to increase the overall efficiency of the engine. The system comprises an exhaust turbocharger, which is in fluid communication with the engine and driven by a supply of exhaust gas from the engine. The driven exhaust turbocharger is configured to supply compressed air to the engine. A boiler is provided to transfer heat from the exhaust gas to a heat-transfer fluid to generate a heat-transfer vapor. The vapor operates to drive a vapor turbocharger to supply additional compressed air to the engine. The vapor is further used to absorb heat from a coolant fluid used in an engine cooling system before a vapor compressor compresses the vapor back to a semi-saturated state and returns it to the boiler to complete a vapor cycle. A method for implementing the above-mentioned system is also provided.

Systems, methods, and vehicles for use with internal combustion engines comprising combustion chambers that produce exhaust gases that include a Stirling engine having a hot side and a cold side with the hot side being in thermal contact with exhaust gases produced by the internal combustion engine. The Stirling engine is configured to be powered by heat from the exhaust gases during operation of the internal combustion engine, and a compressor powered by the Stirling engine is configured to provide compressed air to combustion chambers of the internal combustion engine.