A constant density heat exchanger is provided. The constant density heat exchanger includes a housing extending between a first end and a second end and defining a chamber having an inlet and an outlet. A first flow control device is positioned at the inlet of the chamber and movable between an open position in which a working fluid is permitted into the chamber and a closed position in which the working fluid is prevented from entering the chamber. A second flow control device is positioned at the outlet of the chamber and movable between an open position in which the working fluid is permitted to exit the chamber and a closed position in which the working fluid is prevented from exiting the chamber. A heat exchange fluid imparts thermal energy to the volume of working fluid held at constant density within the chamber by the first and second control devices.

A constant density heat exchanger is provided. The constant density heat exchanger includes a housing extending between a first end and a second end and defining a chamber having an inlet and an outlet. A first flow control device is positioned at the inlet of the chamber and movable between an open position in which a working fluid is permitted into the chamber and a closed position in which the working fluid is prevented from entering the chamber. A second flow control device is positioned at the outlet of the chamber and movable between an open position in which the working fluid is permitted to exit the chamber and a closed position in which the working fluid is prevented from exiting the chamber. A heat exchange fluid imparts thermal energy to the volume of working fluid held at constant density within the chamber by the first and second control devices.

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.

An energy conversion apparatus may include an engine assembly, such as a monolithic engine assembly. The engine assembly may include a first monolithic body segment and a plurality of second monolithic body segments directly coupled or directly couplable to the first monolithic body segment. The first monolithic body segment may define a combustion chamber and a recirculation pathway in fluid communication with the combustion chamber. The recirculation pathway may be configured to recirculate combustion gas through the combustion chamber. The plurality of second monolithic body segments may respectively define at least a portion of a piston chamber and a plurality of working-fluid pathways fluidly communicating with the piston chamber.

An energy conversion apparatus may include an engine assembly, such as a monolithic engine assembly. The engine assembly may include a first monolithic body segment and a plurality of second monolithic body segments directly coupled or directly couplable to the first monolithic body segment. The first monolithic body segment may define a combustion chamber and a recirculation pathway in fluid communication with the combustion chamber. The recirculation pathway may be configured to recirculate combustion gas through the combustion chamber. The plurality of second monolithic body segments may respectively define at least a portion of a piston chamber and a plurality of working-fluid pathways fluidly communicating with the piston chamber.

Exemplary embodiments are directed to a heat engine. The heat engine includes a pipe that defines a continuous internal path. The pipe includes a first pipe section and a second pipe section. The heat engine includes a first piston disposed within the first pipe section. The heat engine includes a second piston disposed within the second pipe section. The first and second pistons are magnetically linked to travel along the continuous internal path of the pipe.

A thermoacoustic device includes a process volume which is filled with a working fluid through which the acoustic wave propagates. The thermoacoustic device further includes an acoustic network comprising a tubular loop configured with a passage providing an opening in the loop and configured as acoustic circuit provided with a compliance volume, a thermo-acoustic core and an inertance volume. Within the loop, the thermoacoustic core is at a first side thereof adjacent to the passage at a first path length through the loop, and at its second side, opposite to the first side, the thermoacoustic core is at a second path length from the passage. The thermoacoustic device includes within the loop a spring-type partitioning element that is configured to close off the cross-section of the tube and to be impermeable for the working fluid while allowing transmission of pressure waves in the working fluid through the spring-type partitioning element.

A thermoacoustic device includes a process volume which is filled with a working fluid through which the acoustic wave propagates. The thermoacoustic device further includes an acoustic network comprising a tubular loop configured with a passage providing an opening in the loop and configured as acoustic circuit provided with a compliance volume, a thermo-acoustic core and an inertance volume. Within the loop, the thermoacoustic core is at a first side thereof adjacent to the passage at a first path length through the loop, and at its second side, opposite to the first side, the thermoacoustic core is at a second path length from the passage. The thermoacoustic device includes within the loop a spring-type partitioning element that is configured to close off the cross-section of the tube and to be impermeable for the working fluid while allowing transmission of pressure waves in the working fluid through the spring-type partitioning element.

An integrated wind and solar solution is provided, including a solar energy collection assembly (100) and a vertical axis wind turbine (400), combined to provide an integrated power output. In preferred embodiments, the vertical axis wind turbine is positioned above the solar energy collection assembly. Concentrating solar mirror collectors (116) are used to direct sunlight to a heat engine (250), which converts the collected heat energy into rotary motion. Rotary motion from the heat engine and from the vertical axis wind turbine preferably are on the same rotating axis (600), to facilitate load sharing between these two sources. A dual axis azimuth-altitude solar panel alignment tracking system is used in order to boost the energy conversion capability of the solar energy collectors.

A working cylinder is provided, comprising at least one disc-like displacer (120) rotatably supported in a cylindrical block (114), which displacer (120) is arranged between two annular flanges (110) extending radially inwards from said block (114) on each sides of said displacer (120) such that said displacer (120) will be arranged in parallel with said flanges (110) upon rotation, wherein at least one of said flanges (110) comprises a plurality of sections including a first section (112a) having a first temperature, a second section (112b) having a second temperature being lower than said first temperature, and two insulating sections (112c, 112d) completely preventing contact between said first section (112a) and said second section (112b), and wherein said displacer (120) comprises a cutout (122) for rotating a volume of working fluid across the sections (112), which cutout is dimensioned such that for every rotational position it does not overlap the first section (112a) and the second section (112b) at the same time.