A method for pressurisation of a working gas in a Stirling engine assembly for use in a thermal energy plant, the Stirling engine assembly including: a Stirling engine including an expansion cylinder and a compression cylinder, wherein the expansion and compression cylinders are configured in a V-arrangement; a regenerator; a cooler and a heater; an accumulator, the accumulator being in fluidic connection with the expansion and/or compression cylinders of the Stirling engine; and a low pressure receptacle including the working gas. The method includes: providing working gas to the accumulator from the low pressure receptacle; providing a pressurisation fluid to the accumulator to reduce the volume for the working gas in the accumulator, thereby increasing the pressure of the working gas in the accumulator; and displacing the pressurised working gas from the accumulator to the expansion and/or compression cylinder.

Disclosed is a thermoacoustic engine having: resonance pipes including a working gas; motors; and a branch pipe, where each of the motors has a regenerator, a heater, and a cooler, a temperature gradient is given between both ends of the regenerator to generate self-excited oscillation of the working gas, a channel cross-sectional area of the resonance pipe that is coupled to the heater is expanded by a same amplification factor of a work flow based on the self-excited oscillation or by an amplification factor within a range of ±30% of the amplification factor of the work flow to a channel cross-sectional area of a resonance pipe that is coupled to the cooler, and a channel cross-sectional area of the regenerator is set by 4 to 36 times of the channel cross-sectional area of the resonance pipe that is coupled to the cooler.

Disclosed is a thermoacoustic engine having: resonance pipes including a working gas; motors; and a branch pipe, where each of the motors has a regenerator, a heater, and a cooler, a temperature gradient is given between both ends of the regenerator to generate self-excited oscillation of the working gas, a channel cross-sectional area of the resonance pipe that is coupled to the heater is expanded by a same amplification factor of a work flow based on the self-excited oscillation or by an amplification factor within a range of ±30% of the amplification factor of the work flow to a channel cross-sectional area of a resonance pipe that is coupled to the cooler, and a channel cross-sectional area of the regenerator is set by 4 to 36 times of the channel cross-sectional area of the resonance pipe that is coupled to the cooler.

A floating coil configuration for a compressor of a closed cycle cryogenic cooler, the coil configuration comprises a coil having a positive end and a negative end and first and second springs concentrically located within the coil, each spring having a first end and a second end. The positive end of the coil is coupled to the first end of the first spring and the negative end of the coil is coupled to the second end of the second spring. The second end of the first spring is electrically coupled to the first end of the second spring such that the first and second springs define an electrical path across the coil.

An engine body may include a piston body comprising a piston chamber and a regenerator body comprising a regenerator conduit. An engine body may include a working-fluid heat exchanger body comprising a plurality of working-fluid pathways fluidly communicating between the piston chamber and the regenerator conduit. Additionally, or alternatively, an engine body may include a heater body comprising a plurality of heating fluid pathways and the plurality of working-fluid pathways. The heating fluid pathways may have a heat transfer relationship with the working fluid pathways. The working-fluid pathways may fluidly communicate between the piston chamber and the regenerator conduit. The engine body may include a monolithic body defined at least in part by the piston body, the regenerator body, and the working-fluid heat exchanger body, and/or defined at least in part by the piston body, the regenerator body, and the heater body.

Method and system for efficient energy recovery from heat source with external combustion engine. Invention include sequentially operating drive mechanism for power pistons and displacement pistons of gamma type Stirling engine, providing nearly ideal pistons operation sequence. Stirling engine is supplemented with working flow fluid control and separation member between working fluid reheater and rest of the engine during high pressure stage. Working fluid is circulated in flow control via one or more consecutive displacement cylinder/power cylinder stages before reheating. Control system is directing working fluid from inlet port to the first displacement cylinder, further to the first power cylinder and after expansion either to reheating or to the next displacement cylinder. Low temperature working fluid is finally directed back to the counter flow type reheater.

The present invention is characterized in that the linear reciprocating motion of a displacer piston and a rod is converted into the rotating motion of a wheel body in accordance with a thermal change, which is generated by supplying waste heat from equipment to a portion of a displacer cylinder of a Stirling engine, in that magnets mounted to the wheel body, which is linked to the cylinder rod, are rotated in a circumferential direction to form a magnetic field and to consequently generate electric power in conjunction with power line coils provided around the magnets, in that the centrifugal force generated by the rotation of the wheel body enables the cylinder rod to more powerfully perform a linear motion, and in that a bottom plate, which is coupled to the lower portion of the cylinder body, is provided with heat conduction fins to increase the heat transfer area.

The present invention is characterized in that the linear reciprocating motion of a displacer piston and a rod is converted into the rotating motion of a wheel body in accordance with a thermal change, which is generated by supplying waste heat from equipment to a portion of a displacer cylinder of a Stirling engine, in that magnets mounted to the wheel body, which is linked to the cylinder rod, are rotated in a circumferential direction to form a magnetic field and to consequently generate electric power in conjunction with power line coils provided around the magnets, in that the centrifugal force generated by the rotation of the wheel body enables the cylinder rod to more powerfully perform a linear motion, and in that a bottom plate, which is coupled to the lower portion of the cylinder body, is provided with heat conduction fins to increase the heat transfer area.

Systems and methods for converting energy are provided. In one aspect, the system includes a closed cycle engine defining a cold side. The system also includes a bottoming-cycle loop. A pump is operable to move a working fluid along the bottoming-cycle loop. A cold side heat exchanger is positioned along the bottoming-cycle loop in a heat exchange relationship with the cold side of the closed cycle engine. A constant density heat exchanger is positioned along the bottoming-cycle loop downstream of the cold side heat exchanger and upstream of an expansion device. The constant density heat exchanger is operable to hold a volume of the working fluid flowing therethrough at constant density while increasing, via a heat source, the temperature and pressure of the working fluid. The expansion device receives the working fluid at elevated temperature and pressure and extracts thermal energy from the working fluid to produce work.

Systems and methods for converting energy are provided. In one aspect, the system includes a closed cycle engine defining a cold side. The system also includes a bottoming-cycle loop. A pump is operable to move a working fluid along the bottoming-cycle loop. A cold side heat exchanger is positioned along the bottoming-cycle loop in a heat exchange relationship with the cold side of the closed cycle engine. A constant density heat exchanger is positioned along the bottoming-cycle loop downstream of the cold side heat exchanger and upstream of an expansion device. The constant density heat exchanger is operable to hold a volume of the working fluid flowing therethrough at constant density while increasing, via a heat source, the temperature and pressure of the working fluid. The expansion device receives the working fluid at elevated temperature and pressure and extracts thermal energy from the working fluid to produce work.