A method and apparatus that reduces the dead volume in a heat engine or heat pump, such as a duplex Stirling or Vuilleumier cycle device, by nesting the components of the displacer and regenerator such that nearly all working fluid is purged from the interstices of the regenerator elements and all other working fluid spaces that are not involved in doing useful work at each portion of the cycle. Particularly, a more scalable and efficient method and apparatus for providing solar air conditioning or refrigeration by means of a heated cylinder that alternately pressurizes and depressurizes a separate cooling cylinder by directly transferring thermally induced pressure changes to that cooling cylinder at optimized times in the cycle, under the control of a numerically controlled actuation system that can cycle at a much lower rate than mechanically coupled or harmonically phased systems.

A method and apparatus that reduces the dead volume in a heat engine or heat pump, such as a duplex Stirling or Vuilleumier cycle device, by nesting the components of the displacer and regenerator such that nearly all working fluid is purged from the interstices of the regenerator elements and all other working fluid spaces that are not involved in doing useful work at each portion of the cycle. Particularly, a more scalable and efficient method and apparatus for providing solar air conditioning or refrigeration by means of a heated cylinder that alternately pressurizes and depressurizes a separate cooling cylinder by directly transferring thermally induced pressure changes to that cooling cylinder at optimized times in the cycle, under the control of a numerically controlled actuation system that can cycle at a much lower rate than mechanically coupled or harmonically phased systems.

In a Stirling refrigerator, a regenerator has a low-temperature end and a high-temperature end. A plurality of protrusions, which thermally contact with the low-temperature end of the regenerator, are formed on a low-temperature heat exchanger. The low-temperature heat exchanger has a recess between the protrusions, and the recess forms a flowing groove through which a working gas flows. The regenerator may contain a mesh regenerator material.

A thermoacoustic engine is provided that uses acoustic energy to operate a piston in a double-acting action. The acoustic energy is amplified as a sound wave travels through the thermoacoustic engine. The amplified acoustic energy is extracted and converted into usable electrical energy.

A thermoacoustic engine is provided that uses acoustic energy to operate a piston in a double-acting action. The acoustic energy is amplified as a sound wave travels through the thermoacoustic engine. The amplified acoustic energy is extracted and converted into usable electrical energy.

A combined power generation system based on geothermal energy and solar energy and a power generation method thereof are provided. The system includes: at least three injection wells; at least three production wells; at least three connected paths in a reservoir connected with gas outlets of the at least three injection wells and gas inlets of the at least three production wells; at least three geothermal turbines having gas inlets connected with gas outlets of the at least three production wells; a gas cooler; a first regenerator having a high-pressure gas inlet connected with a gas outlet of the upmost production well; a second regenerator having a high-pressure gas inlet connected with one geothermal turbine; a solar receiver having a gas inlet connected with the second regenerator; and a solar turbine having a gas inlet connected with the solar receiver and a gas outlet connected with the second regenerator.

A combined power generation system based on geothermal energy and solar energy and a power generation method thereof are provided. The system includes: at least three injection wells; at least three production wells; at least three connected paths in a reservoir connected with gas outlets of the at least three injection wells and gas inlets of the at least three production wells; at least three geothermal turbines having gas inlets connected with gas outlets of the at least three production wells; a gas cooler; a first regenerator having a high-pressure gas inlet connected with a gas outlet of the upmost production well; a second regenerator having a high-pressure gas inlet connected with one geothermal turbine; a solar receiver having a gas inlet connected with the second regenerator; and a solar turbine having a gas inlet connected with the solar receiver and a gas outlet connected with the second regenerator.

An efficient stirling engine comprises an expansion chamber with a heater and a compression chamber with a cooler, wherein the two chambers are connected through a regenerator. A passage between the heater and the expansion chamber is provided with a first valve system, a passage between the cooler and the compression chamber is provided with a second valve system, the first valve system can close or open the passage between the heater and the expansion chamber, and the second valve system can close or open the passage between the cooler and the compression chamber. After adopting the structure above, when a heating end is heated to expand, a cooling end at the other end is closed, and on the contrary, when the cooling end is cooled to shrink, the heating end at the other end is closed, so that the heating energy is fully used, so as to increase the efficiency of the stirling engine.

An efficient stirling engine comprises an expansion chamber with a heater and a compression chamber with a cooler, wherein the two chambers are connected through a regenerator. A passage between the heater and the expansion chamber is provided with a first valve system, a passage between the cooler and the compression chamber is provided with a second valve system, the first valve system can close or open the passage between the heater and the expansion chamber, and the second valve system can close or open the passage between the cooler and the compression chamber. After adopting the structure above, when a heating end is heated to expand, a cooling end at the other end is closed, and on the contrary, when the cooling end is cooled to shrink, the heating end at the other end is closed, so that the heating energy is fully used, so as to increase the efficiency of the stirling engine.

A rotating machine is disclosed and includes a stator defining a circumference, a plurality of first magnet arrays, a rotor, and a first piston. The first magnet arrays are comprised of a plurality of discrete magnets arranged around the circumference of the stator in a first magnetic pattern. The rotor is rotatable about an axis of rotation and defines a main body. The main body defines a first passageway. The first piston includes a plurality of first magnetic elements and is actuated within the first passageway of the rotor. The plurality of discrete magnets are arranged in the first magnetic pattern and are positioned to interact with the magnetic elements of the first piston to create a first magnetic force as the rotor rotates about the axis of rotation. The first magnetic force represents a first amount of force required to actuate the first piston.