A thermal regenerator apparatus is disclosed including a regenerator medium having a plurality of flow passages extending between first and second ports, the flow passages facilitating back and forth fluid flow in a generally transverse direction between the first and second ports while the medium alternatively receives thermal energy from and delivers thermal energy to the fluid. The regenerator medium includes a plurality of overlying foils, each foil having a plurality of channels extending through the foil, the channels having beveled sidewalls. The channels have a width and spacing in the transverse direction and channels in each adjacent overlying foil are transversely offset such that each channel spans between and is in fluid communication with a pair of channels in the adjacent foils and the beveled sidewalls of the channels redirect fluid flow between channels in adjacent foils to form the flow passages. The channels are elongated along the foil in a longitudinal direction orthogonal to the transverse direction and divided by foil bridges extending transversely, the foil bridges being sized to reduce thermal conduction through the medium in the transverse direction.

A thermal regenerator apparatus is disclosed including a regenerator medium having a plurality of flow passages extending between first and second ports, the flow passages facilitating back and forth fluid flow in a generally transverse direction between the first and second ports while the medium alternatively receives thermal energy from and delivers thermal energy to the fluid. The regenerator medium includes a plurality of overlying foils, each foil having a plurality of channels extending through the foil, the channels having beveled sidewalls. The channels have a width and spacing in the transverse direction and channels in each adjacent overlying foil are transversely offset such that each channel spans between and is in fluid communication with a pair of channels in the adjacent foils and the beveled sidewalls of the channels redirect fluid flow between channels in adjacent foils to form the flow passages. The channels are elongated along the foil in a longitudinal direction orthogonal to the transverse direction and divided by foil bridges extending transversely, the foil bridges being sized to reduce thermal conduction through the medium in the transverse direction.

A monolithic heat exchanger body for inputting heat to a closed-cycle engine may include a plurality of heating walls and heat sink, such as a plurality of heat transfer regions. The plurality of heating walls may be configured and arranged in an array of spirals or spiral arcs relative to a longitudinal axis of an inlet plenum. Adjacent portions of the plurality of heating walls may respectively define a corresponding plurality of heating fluid pathways therebetween, for example, fluidly communicating with the inlet plenum. At least a portion of the heat sink may be disposed about at least a portion of the monolithic heat exchanger body. The heat sink may include a plurality of working-fluid bodies, for example, including a plurality of working-fluid pathways that have a heat transfer relationship with the plurality of heating fluid pathways. Respective ones of the plurality of heat transfer regions may have a heat transfer relationship with a corresponding semiannular portion of the plurality of heating fluid pathways. Respective ones of the plurality of heat transfer regions may include a plurality of working-fluid pathways fluidly communicating between a heat input region and a heat extraction region.

A monolithic heat exchanger body for inputting heat to a closed-cycle engine may include a plurality of heating walls and heat sink, such as a plurality of heat transfer regions. The plurality of heating walls may be configured and arranged in an array of spirals or spiral arcs relative to a longitudinal axis of an inlet plenum. Adjacent portions of the plurality of heating walls may respectively define a corresponding plurality of heating fluid pathways therebetween, for example, fluidly communicating with the inlet plenum. At least a portion of the heat sink may be disposed about at least a portion of the monolithic heat exchanger body. The heat sink may include a plurality of working-fluid bodies, for example, including a plurality of working-fluid pathways that have a heat transfer relationship with the plurality of heating fluid pathways. Respective ones of the plurality of heat transfer regions may have a heat transfer relationship with a corresponding semiannular portion of the plurality of heating fluid pathways. Respective ones of the plurality of heat transfer regions may include a plurality of working-fluid pathways fluidly communicating between a heat input region and a heat extraction region.

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.

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.

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.

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.

The articulated plenum (1) forms an intake pipe (3) which is ended with tight ball joint links (16) held by restraining means (17), said plenum (1) connecting a heat source (39) to an expansion cylinder (32) and including a plenum inlet orifice (4), a plenum outlet orifice (6) which receives a valve seat (9), and an actuator orifice (8) which receives an intake valve actuator (50) which controls a valve (10), the latter engaging with the valve seat (9) to close the intake pipe (3).

The articulated plenum (1) forms an intake pipe (3) which is ended with tight ball joint links (16) held by restraining means (17), said plenum (1) connecting a heat source (39) to an expansion cylinder (32) and including a plenum inlet orifice (4), a plenum outlet orifice (6) which receives a valve seat (9), and an actuator orifice (8) which receives an intake valve actuator (50) which controls a valve (10), the latter engaging with the valve seat (9) to close the intake pipe (3).