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.

The invention described herein provides new devices suitable for effectively converting relatively low temperature differences into useful work (e.g., for generating electrical power), related systems, and methods of using and developing such devices/systems. The devices are characterized in, inter alia, comprising an at least partially enclosed moveable component (e.g., a piston), a closed pressurized gas system comprising sizeable void spaces, and a closed temperature modifying liquid system having portions that obtain temperature characteristics from two sources, which are alternatingly dispensed as droplets into the pressurized gas, creating a pressure/temperature difference in the gas which causes the moveable component to move back and forth along a stroke distance that does not include the void spaces, the pressure of the gas and liquid being at substantially balanced when the device is ready for operation.

The invention described herein provides new devices suitable for effectively converting relatively low temperature differences into useful work (e.g., for generating electrical power), related systems, and methods of using and developing such devices/systems. The devices are characterized in, inter alia, comprising an at least partially enclosed moveable component (e.g., a piston), a closed pressurized gas system comprising sizeable void spaces, and a closed temperature modifying liquid system having portions that obtain temperature characteristics from two sources, which are alternatingly dispensed as droplets into the pressurized gas, creating a pressure/temperature difference in the gas which causes the moveable component to move back and forth along a stroke distance that does not include the void spaces, the pressure of the gas and liquid being at substantially balanced when the device is ready for operation.

A monolithic heater body may include a combustor body, a hot-side heat exchanger body, and an eductor body. The combustor body may define a combustion chamber and a conditioning conduit circumferentially surrounding the combustion chamber. The conditioning conduit may fluidly communicate with the combustion chamber at a distal portion of the combustion chamber. The hot-side heat exchanger body may define a hot-side heat exchanger that includes a heating fluid pathway fluidly communicating with a proximal portion of the combustion chamber. The eductor body may define an eduction pathway fluidly communicating with a downstream portion of the heating fluid pathway and a proximal portion of the conditioning conduit.

A monolithic heater body may include a combustor body, a hot-side heat exchanger body, and an eductor body. The combustor body may define a combustion chamber and a conditioning conduit circumferentially surrounding the combustion chamber. The conditioning conduit may fluidly communicate with the combustion chamber at a distal portion of the combustion chamber. The hot-side heat exchanger body may define a hot-side heat exchanger that includes a heating fluid pathway fluidly communicating with a proximal portion of the combustion chamber. The eductor body may define an eduction pathway fluidly communicating with a downstream portion of the heating fluid pathway and a proximal portion of the conditioning conduit.

An actuator device includes a housing that defines an enclosed volume region, the housing comprising a movable surface such that at least a portion of the housing is expandable between an expanded state to a contracted state, and the enclosed volume region having a characteristic dimension that is defined as a cube root of an average of a volume of the enclosed volume region in the expanded state and in the contracted state, a working fluid within the enclosed volumetric region, the working fluid comprising a substantially transparent compressible fluid and electromagnetic (EM) radiation-absorbing solid elements distributed within the compressible fluid, wherein the solid elements have an absorptivity in a particular range of EM radiation wavelengths, a heating system for directing thermal energy into the working fluid at predetermined times, and wherein the housing includes an EM radiation transmitting portion having a sufficient area and a sufficient transparency such that more than 25% of the thermal energy directed into the working fluid by the heating means is radiative emitted through the EM radiation transmitting portion as black body EM radiation emitted by the solid elements of the working fluid.

An actuator device includes a housing that defines an enclosed volume region, the housing comprising a movable surface such that at least a portion of the housing is expandable between an expanded state to a contracted state, and the enclosed volume region having a characteristic dimension that is defined as a cube root of an average of a volume of the enclosed volume region in the expanded state and in the contracted state, a working fluid within the enclosed volumetric region, the working fluid comprising a substantially transparent compressible fluid and electromagnetic (EM) radiation-absorbing solid elements distributed within the compressible fluid, wherein the solid elements have an absorptivity in a particular range of EM radiation wavelengths, a heating system for directing thermal energy into the working fluid at predetermined times, and wherein the housing includes an EM radiation transmitting portion having a sufficient area and a sufficient transparency such that more than 25% of the thermal energy directed into the working fluid by the heating means is radiative emitted through the EM radiation transmitting portion as black body EM radiation emitted by the solid elements of the working fluid.

A mechanical device includes a working medium, a hot end, a cold end, and first and second volume regulating units. The hot and cold ends are in thermal contact with the working medium during circulation thereof. The first and second volume regulating units are disposed between the hot and cold ends, and are configured to allow passage of the working medium therethrough to perform compression and expansion of the working medium. The volume of the working medium exiting the first volume regulating unit differs from that of the working medium entering the second volume regulating unit. The volume of the working medium entering the first volume regulating unit differs from that of the working medium exiting the second volume regulating unit.

Methods, systems, and devices are provided that may include Stirling cycle configurations and/or linear-to-rotary mechanisms in accordance with various embodiments. Some embodiments include a Stirling cycle device that may include a first hot piston contained within a first hot cylinder and a first cold piston contained within a first cold cylinder. A first single actuator may be configured to couple the first hot piston with the first cold piston such that the first hot piston and the first cold piston are on different thermodynamic circuits. The different thermodynamic circuits may include adjacent thermodynamic circuits. The Stirling cycle configuration may be configured as a single-acting alpha Stirling cycle configuration. Some embodiments include a linear-to-rotary mechanism device. The device may include multiple linkages. The device may include a cam plate coupled with the multiple linkages utilizing a cam and multiple cam followers. The linkages may include Watt linkages.

Methods, systems, and devices are provided that may include Stirling cycle configurations and/or linear-to-rotary mechanisms in accordance with various embodiments. Some embodiments include a Stirling cycle device that may include a first hot piston contained within a first hot cylinder and a first cold piston contained within a first cold cylinder. A first single actuator may be configured to couple the first hot piston with the first cold piston such that the first hot piston and the first cold piston are on different thermodynamic circuits. The different thermodynamic circuits may include adjacent thermodynamic circuits. The Stirling cycle configuration may be configured as a single-acting alpha Stirling cycle configuration. Some embodiments include a linear-to-rotary mechanism device. The device may include multiple linkages. The device may include a cam plate coupled with the multiple linkages utilizing a cam and multiple cam followers. The linkages may include Watt linkages.