An assembly with a piston reciprocated with the aid of a floating head in fluid communication with the piston. The assembly may utilize a floating head that is shifted in position to promote reciprocation of the piston through the aid of pressure supplied to the floating head from a pressure volume regulator. Alternatively, the floating head may be in fluid communication with the piston at one side of the head and isolated at the other side. In this manner changing volume and pressure at this other side of the head during reciprocation may ultimately lead to floating head movement toward the piston, thereby promoting the continued reciprocation. Additional efficiencies may also be realized through unique hydraulic layouts for both operating and working fluid circulations.

An apparatus, system and method for generating power, utilising a novel mono-block reciprocating piston engine with reduced or zero harmful emissions. The mono-block comprises a composite internal combustion IC section and Organic Rankine Cycle ORC section. The mono-block engine comprises two or more cylinders each having a piston housed therein; a composite internal combustion IC section controlling the displacement of at least one of the pistons and; an Organic Rankine Cycle ORC section controlling the displacement of at least one of the pistons; wherein the IC and ORC pistons connect to and drive a common crankshaft of the mono-block engine power plant; and wherein the Organic Rankine Cycle operates by the heat generated by the combustion in the internal combustion section, and the displacement of the pistons in the ORC section is achieved by injecting heated and pressurised ORC fluid.

An expander system for recovering waste heat, a waste heat recovery system including such an expander system, a vehicle including such a waste heat recovery system and a method for manufacturing such an expander system. The expander system includes a shaft and a coupling portion including a first sealing unit and a second sealing unit. The shaft is inserted through the coupling portion to an expanding unit. The first sealing unit and the second sealing unit are arranged facing one another along the shaft. The first sealing unit and the second sealing unit are configured to seal the shaft in an axial direction relative to the shaft.

A waste heat recovery system, based on a Brayton cycle, comprises a heater configured to circulate carbon dioxide vapor in heat exchange relationship with a hot fluid to heat the carbon dioxide vapor. An expander is coupled to the heater and configured to expand the carbon dioxide vapor. A compressor is configured to compress the carbon dioxide vapor fed through a cooler and a heat exchanger is adapted to circulate the carbon dioxide vapor from the expander to the cooler in heat exchange relationship with the carbon dioxide vapor from the compressor to the heater, wherein the expander and the compressor are mechanically coupled volumetric machines.

A waste heat recovery system, based on a Brayton cycle, comprises a heater configured to circulate carbon dioxide vapor in heat exchange relationship with a hot fluid to heat the carbon dioxide vapor. An expander is coupled to the heater and configured to expand the carbon dioxide vapor. A compressor is configured to compress the carbon dioxide vapor fed through a cooler and a heat exchanger is adapted to circulate the carbon dioxide vapor from the expander to the cooler in heat exchange relationship with the carbon dioxide vapor from the compressor to the heater, wherein the expander and the compressor are mechanically coupled volumetric machines.

Disclosed is a thermodynamic cycle process, performing transfer between mechanical and heat energies, by changing a state of a fluid, including: an expansion of the fluid, an energy retrieval from the fluid expansion, a step of powering a liquid pump or a gas compressor with the retrieved energy, using a cyclic free piston expander which alternatively changes direction of the free piston sliding: by alternatively: closing the fluidic communication between the both opposite sides of the free piston, to make different from each other the pressures applied respectively thereon, so the free piston slides in a first direction, opening a fluidic communication between both opposite sides of the free piston, to make equal to each other the pressures applied respectively thereon, so the free piston slides in a second direction opposite to the first direction, the free piston sliding, directly and mechanically, opening and closing, the fluidic communication.

An expander system for recovering waste heat, a waste heat recovery system including such an expander system, a vehicle including such a waste heat recovery system and a method for manufacturing such an expander system. The expander system includes a shaft and a coupling portion including a first sealing unit and a second sealing unit. The shaft is inserted through the coupling portion to an expanding unit. The first sealing unit and the second sealing unit are arranged facing one another along the shaft. The first sealing unit and the second sealing unit are configured to seal the shaft in an axial direction relative to the shaft.

A power system is configured to generate mechanical energy from supercritical carbon dioxide in a closed loop. The power system includes a compressor that yields a high pressure supercritical carbon dioxide. A heat exchanger is operatively connected to the compressor and yields a high enthalpy supercritical carbon dioxide. A rotary engine is operatively connected to the heat exchanger and configured to convert thermal energy from the high enthalpy supercritical carbon dioxide into mechanical energy and an output supercritical carbon dioxide. A pressure differential orifice is operatively coupled to the rotary engine and to the heat exchanger and configured to decrease the temperature and the pressure of the output supercritical carbon dioxide resulting in a low pressure low temperature supercritical carbon dioxide. The low pressure low temperature supercritical carbon dioxide is heated in the heat exchanger and the renters the compressor completing the closed loop.

A power system is configured to generate mechanical energy from supercritical carbon dioxide in a closed loop. The power system includes a compressor that yields a high pressure supercritical carbon dioxide. A heat exchanger is operatively connected to the compressor and yields a high enthalpy supercritical carbon dioxide. A rotary engine is operatively connected to the heat exchanger and configured to convert thermal energy from the high enthalpy supercritical carbon dioxide into mechanical energy and an output supercritical carbon dioxide. A pressure differential orifice is operatively coupled to the rotary engine and to the heat exchanger and configured to decrease the temperature and the pressure of the output supercritical carbon dioxide resulting in a low pressure low temperature supercritical carbon dioxide. The low pressure low temperature supercritical carbon dioxide is heated in the heat exchanger and the renters the compressor completing the closed loop.

A system for recovery of energy in residue gases, comprising at least two energy conversion units (1), including a combustion chamber (2) having a fuel inlet (9), and a Sterling engine (4) having a heat exchanger (3) with a set of tubes containing working fluid, a portion of the heat exchanger extending into the combustion chamber (2). The system further comprises a pressure control system including a high-pressure reservoir (21) of working fluid, a low-pressure reservoir (22) of working fluid, a pressure pump (23) configured to maintain a pressure difference between the reservoirs, and a control arrangement (31, 32, 33) to regulate a pressure in the fluid circuit.