Abstract: Techniques are disclosed for systems and methods to reduce mechanical vibrations within a cryocooler/refrigeration system configured to provide cryogenic and/or general cooling of a device or sensor system. A cryocooler includes a motor driver controller configured to receive operational parameters and generate motor driver control signals and/or balancer system control signals based, at least in part, on the received operational parameters, and a motor driver configured to receive the control signals and generate drive signals to drive a motor and/or a balancer system of the cryocooler. The cryocooler includes a motorized and/or actively balanced expander configured to drive and/or balance motion of a displacer of the expander. The expander includes a magnet ring fixed to the displacer and a motor coil disposed within a cylinder head of the motorized and/or actively balanced expander.

Abstract: A pneumatic cryocooler using a pneumatic motor for use in cryogenically cooling superconductors, which pneumatic cryocooler is capable of operation in strong magnetic fields.

Abstract: Process and plant for the production of liquid hydrogen with a liquefier that has a variable cooling power dependent on the electrical power consumed. The liquefier is supplied with electricity by a first source of electricity at least one additional source of electricity that provides an intermittent or variable amount of electricity over time. Liquid hydrogen is produced at first thermodynamic conditions when the liquefier is supplied with a predetermined nominal electrical energy level and produced at subcooled conditions, with respect to the first thermodynamic conditions, when electricity supplied to the liquefier exceeds the nominal level.

Abstract: A Stirling refrigerator serves as a reciprocating motion engine and has: a casing; a cylinder arranged within the casing; a piston capable of being reciprocated within the cylinder in a reciprocating direction as being uniaxial; a control circuit electrically controlling movement of the piston; a damping unit provided at one end side of the casing in the reciprocating direction via a first connection part and a second connection part serving as connection parts; and a vibration detection board arranged via an attachment body on the second connection part, said vibration detection board serving as a vibration detector to detect a vibration in the reciprocating direction, caused by the reciprocating movement of the piston, to transmit it to the control circuit.

Abstract: A method and apparatus for detecting the displacement amplitude of an armature of a linear motor or alternator that is drivingly coupled to a load or prime mover. The method and apparatus require only three inputs all derived from the input terminals of the linear motor or alternator: (1) the voltage measured across the linear motor terminals; (2) the current consumed by the linear motor; and (3) the phase between the voltage and current. The three inputs are sensed at the terminals of the linear motor or alternator and used to perform mathematical calculations in the microcomputer of a control system or controller. The mathematical calculations are based on equivalent circuits that are modifications of the equivalent circuit for the linear motor or alternator. The detected displacement amplitude can be used by a controller to limit the displacement amplitude of the armature to prevent collisions.

Abstract: A heat pump is disclosed that has a hot displacer section and a cold displacer section with a linear actuator section disposed between the hot and cold displacer sections. By providing the linear actuator section between the displacers, the shafts that couple the actuators in the linear actuator section to their respective displacer is shorter than if the linear actuator section were located at the bottom of the cold displacer. The shorter shaft can be less stiff to avoid buckling. Due to a lesser propensity to cock, there is less friction of the shaft when reciprocating.

Abstract: A GM cryocooler includes a compressor having a compressor discharge port and a compressor suction port, a displacer capable of reciprocating in an axial direction, a displacer cylinder accommodating the displacer, a drive piston connected to the displacer so as to drive the displacer in the axial direction, a drive chamber in which the drive piston is driven, a main pressure switching valve configured to alternately connect the displacer cylinder to the compressor discharge port and the compressor suction port, an auxiliary pressure switching valve configured to alternately connect the drive chamber to the compressor discharge port and the compressor suction port, and a buffer volume connected between the auxiliary pressure switching valve and the compressor.

Abstract: There is provided a cryocooler including a cryocooler cylinder, a pressure switching valve that generates a periodic pressure fluctuation inside the cryocooler cylinder, and a sensor that measures a periodic deformation of the cryocooler cylinder, which is caused by the periodic pressure fluctuation inside the cryocooler cylinder.

Abstract: Provided is an apparatus and method for transferring or exchanging thermal energy between two thermal reservoirs, for converting energy from thermal energy into another form of energy, or for converting energy from another form of energy into thermal energy. A body force per unit mass generating apparatus can be employed to modify a specific heat capacity of a working material. A work exchange apparatus, such as a compressor expander, can be employed to do work on the working material, or allow the working material to do work on the work exchange apparatus.

Abstract: A thermodynamic apparatus that includes a displacer within a cylinder is disclosed. The displacer reciprocates within the cylinder by a linear actuator that includes electrical coils, an armature, and a coil spring system. The spring system includes collinear first and second coil springs of opposite sense. First ends of the springs are captured in a first plate; second ends of the springs are captured in a second plate. Without constraint, the springs can compensate to forces by bending, rotating, increasing in diameter, and combinations thereof. In certain applications, such as the heat pump, bending should be minimized. By selecting the points of capture of the hooks at the ends of the springs in the plates, bending force of the first spring counteracts the bending force of the second spring.

Abstract: The present invention features a hot air engine system designed to improve the overall efficiency of the engine. The engine features a mechanism for oscillating a piston cylinder such that the pivot point is at the bottom of the cylinder. This mechanism improves the overall efficiency of the engine by reducing the side forces that are produced when the back and forth motion of a piston is converted into rotational movement. To achieve this mechanism, a set of arms is attached to the piston cylinder and extend into the displacer chamber and are attached to the displacer. When the displacer oscillates during operation of the engine, the arms swing, and the cylinder rod swings in line with the arms, causing the cylinder rod to pivot at the bottom of the cylinder. This engine system runs on almost boiling water and can use industrial wastewater as a fuel source.

Abstract: The various embodiments described herein include methods for testing low temperature components. In some embodiments, a cryogenic testing system includes: (1) a cryostat chamber configured to maintain a sample at temperatures below a threshold temperature, where the sample includes a two-dimensional array of components to be tested, the two-dimensional array comprising a first number (n) of columns and a second number (m) of rows; (2) a probe card including: (a) a set of n column connectors configured to couple to respective columns of the two-dimensional array; and (b) a set of m row connectors configured to couple to respective rows of the two-dimensional array; and (3) a cryogenic connector for communicatively coupling the probe card to a processing unit outside of the cryostat chamber.

Abstract: The inventor claims a heat engine that follows a modification of the Stirling thermodynamic heat engine cycle; the monatomic working fluid is a saturated gas at the beginning of the isothermal compression stage, and ends up a mixed-phase fluid at the end of the compression. A proximate piston compresses and expands surrounding ideal gas helium, to function as a regeneration mechanism of this Stirling cycle and minimize the temperature difference during heat transfer. This cycle takes advantage of the temperature-dependent attractive intermolecular forces of the working fluid to assist in compressing the working fluid partially into a liquid, reducing the input compression work and increasing the overall heat engine efficiency.

Abstract: A pulse tube cryocooler is furnished with a second-stage cooling stage and an insert. The second-stage cooling stage has a lateral-surface opening, and a first heat-exchange surface extending in a sideways direction from the lateral-surface opening into the second-stage cooling stage. The insert includes a base-end portion fixedly fitted into the second-stage cooling stage to plug the lateral-surface opening, and a second heat-exchange surface that extends in the sideways direction from the base-end portion and is disposed inside the second-stage cooling stage, opposing the first heat-exchange surface. Between the first heat-exchange surface and the second heat-exchange surface the insert forms a clearance that flows a working gas, bringing both the first heat-exchange surface and the second heat-exchange surface into contact with the working gas.

Abstract: A cryocooler includes: a housing furnished with a housing bottom surface; a displacer furnished with a displacer upper surface between the housing bottom surface and which an upper gas chamber is formed, and being enabled to reciprocate axially with respect to the housing; a housing gas flow path formed in the housing and opening onto the upper gas chamber; a displacer upper gas flow path formed in the displacer and opening onto the upper gas chamber; and a gas-guiding flow channel formed in at least either the housing bottom surface or the displacer upper surface constituting a portion of the upper gas chamber, and interconnecting the housing gas flow path and the displacer upper gas flow path when the displacer is positioned at top-dead center in its axial reciprocation.

Abstract: A method for limiting the amplitude of reciprocation of a piston reciprocating in a cylinder of a free-piston Stirling engine. The method is the combination of both at least partially covering the heat rejecter cylinder port by the piston sidewall during a peak part of the inward reciprocation of the piston and at least partially covering the heat rejecter cylinder port by the displacer sidewall during a peak part of the outward reciprocation of the displacer. The piston and the displacer, at times during their reciprocation, fully cover the effective heat rejecter cylinder port when the piston amplitude of reciprocation is large and approaches the physical limit of the amplitude of reciprocation in order to avoid internal collisions by a reciprocating component.

Abstract: A liquid piston Stirling engine electrical generator, the generator being a linearly reciprocating electrical generator that is powered by a Stirling engine having a liquid piston that is displaced by the cyclic contraction and expansion of a gas resulting from increases and decreases in temperature. The liquid piston and dynamic components of the linear generator are retained within a U-shaped tube or chamber, the tube being oriented in use to consist of a two upwardly extending, first and second vertical segments joining a horizontal segment. A liquid, such as oil or hydraulic fluid, is present in sufficient quantity to fill the horizontal segment and extend upward into the vertical segments.

Abstract: A reduction in a permeability of refrigerant gas is suppressed while increasing a filling factor of regenerator material particles with respect to a stage of a cold head. A cold head includes a stage including regenerator material particle groups, and a metal mesh material partitioning the regenerator material particle groups. The metal mesh material has quadrangular mesh holes each having a length of a long side of 1/10 or more and ½ or less of each of average particle sizes of the regenerator material particle groups.

Abstract: 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.

Abstract: Magnetic refrigerating device improves refrigerating capacity and efficiency by improving the heat exchanging method between a magnetic material and a heat exchanging fluid and devising a magnetic field applying method. The magnetic refrigerating device comprises: a cylindrical active magnetic regenerator (AMR) bed accommodating refrigerant therein; two magnetic materials disposed in the AMR bed in the axial direction, configured to be movable in the axial direction of the AMR bed, and made of material having a magnetocaloric effect; at least two permanent magnets positioned to face the two magnetic materials; a rotary shaft positioned between the two magnetic materials in the AMR bed and positioned between the at least two permanent magnets; and a magnetic rotary movement unit that rotationally moves the permanent magnets about the rotary shaft and that repeatedly moves the permanent magnets and the two magnetic materials closer together and farther apart in association with the rotational movement.

Abstract: A mechanical system, such as cryogenic refrigerator system, is described. The system comprises two or more axial moving elements generating two or more cyclic forces along parallel axes and a vibration attenuation unit. The cyclic forces are provided with common frequency and certain phase difference between them. The vibration attenuation unit is configured for attenuating vibrations corresponding to two or more modes of vibrations characterized by a frequency corresponding to operation frequency of said two or more cyclic forces.

Abstract: An active gas regenerative refrigerator includes a plurality of compressor-expander units, each having a hermetic cylinder with a drive piston configured to be driven reciprocally therein, and a quantity of working fluid in each end of the cylinder. A piston seal in a central portion of the cylinder prevents passage of the working fluid between ends of the cylinder. Movement of the piston to a first extreme results in radial compression of one of the quantities of working fluid in a cylindrical gap formed between one end of the piston and an inner surface of the cylinder, while the other quantity is expanded in the opposite end of the cylinder. The piston includes a plurality of magnets arranged in pairs, with magnets of each pair positioned with like-poles facing each other. A piston drive is configured to couple with transverse magnetic flux regions formed by the magnets.

Abstract: A cooling system includes a first dewar configured to house a first optical imaging device, a second dewar configured to house a second optical imaging device, and a Stirling cycle refrigerator. The Stirling cycle refrigerator can include a compressor, a first expander in fluid communication with the compressor and in thermal communication with the first dewar, and a second expander in fluid communication with the compressor and in thermal communication with the second dewar.

Abstract: A method of using a thermoelectric generator for warming a transmission on a vehicle having an internal combustion engine is provided. The method includes starting the internal combustion engine, thereby generating a hot exhaust gas; circulating coolant through a heating loop in fluid communication with the internal combustion engine and the thermoelectric generator; passing the hot exhaust gas through a hot-side of the thermoelectric generator and circulating the coolant through the cold-side of the thermoelectric generator, thereby transferring heat from the hot exhaust gas to the coolant and generating an electric current; and selectively powering an electric heating element with the electric current. The electric heating element is in thermal communication with a transmission fluid of the transmission.

Abstract: A Stirling cryocooler includes a displacer having a displacer base portion disposed on a center axis and a displacer tip portion aligned along the center axis, extending from the displacer base portion to a working-gas expansion space, and a regenerator disposed surrounding the displacer tip portion such as to guide reciprocating travel of the displacer along the center axis. The displacer tip portion includes a plurality of platelike components arranged along the center axis, with each of the plurality of platelike components being furnished with a component side surface defining a portion of the outer surface of the displacer tip portion. The plurality of platelike components form working gas layers between pairs of adjoining components, and/or are formed of a synthetic resin material.

Abstract: A free-piston Stirling engine that limits piston amplitude and reduces engine power as the piston amplitude increases beyond its maximum power. The inward edge of the heat rejecter cylinder port is located outward of the most inward excursion of the inward end of the piston sidewall during a part of the piston's reciprocation cycle so that the heat rejecter cylinder port is entirely covered by the piston sidewall during an inward portion of the piston reciprocation when the engine is operating at the selected maximum engine power. A leaker port extends from a gas bearing cavity through the piston sidewall and is positioned axially outward from the gas bearing pads of the engine's gas bearing system and vents working gas to the engine's back space at a piston amplitude of reciprocation that exceeds the piston's amplitude of reciprocation at maximum engine power. A resilient damping bumper is attached to the outward end of the piston and a displacer gas cushion is disclosed.

Abstract: A free-piston Stirling engine that limits piston amplitude and reduces engine power as the piston amplitude increases beyond its maximum power. The inward edge of the heat rejecter cylinder port is located outward of the most inward excursion of the inward end of the piston sidewall during a part of the piston's reciprocation cycle so that the heat rejecter cylinder port is entirely covered by the piston sidewall during an inward portion of the piston reciprocation when the engine is operating at the selected maximum engine power. A leaker port extends from a gas bearing cavity through the piston sidewall and is positioned axially outward from the gas bearing pads of the engine's gas bearing system and vents working gas to the engine's back space at a piston amplitude of reciprocation that exceeds the piston's amplitude of reciprocation at maximum engine power. A resilient damping bumper is attached to the outward end of the piston and a displacer gas cushion is disclosed.

Abstract: In a cryogenic refrigerator, a valve switches between a flow passage of a low-pressure refrigerant gas and a flow passage of a high-pressure refrigerant gas. A motor drives the valve. The motor includes a rotor and a stator, the rotor located radially inward of the stator. A casing hermetically houses the rotor and the stator. The stator includes a back yoke and a magnetic member that acts as a magnetic path of an external magnetic field generated outside of the casing, the magnetic member located radially outward of and spaced apart from the back yoke. The magnetic member is hermetically housed in the casing.

Abstract: A method of controlling facility power requirements using a thermoacoustic power device is provided that includes determining energy assets in a facility, controlling the energy assets using an appropriately programmed controller across a network having a security system protocol, monitoring outside temperatures and weather, measuring usage of the energy assets using a temperature sensor or an electrical usage sensor to a load-response signal of an on/off operation and usage of the energy assets to identify a specific energy asset by the controller to determine aggregate energy needs of the energy assets, and using a thermoacoustic power device controlled by the controller to generate electricity and heat according to the monitored temperature, weather and energy assets.

Abstract: The invention relates to a power unit, in particular for a hybrid vehicle, comprising a reciprocating piston engine and comprising a generator which can be in driving engagement therewith, wherein the reciprocating piston engine has at least two pistons, which are guided in at least two cylinders in tandem arrangement, and two counter-rotating crankshafts, which are connected to the pistons by connecting rods and which are mechanically coupled so as to be in phase, wherein a first generator can be driven by the first crankshaft and a second generator can be driven by the second crankshaft.

Abstract: 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.

Abstract: A cryogenic refrigerator includes a cylinder, a displacer accommodated in the cylinder so as to reciprocate inside the cylinder with a gap formed between the periphery of the displacer and the interior surface of the cylinder, and a depressed part formed on at least one of the periphery of the displacer and the interior surface of the cylinder. The ratio of the volume of the depressed part to the volume of the gap satisfies a condition of 8?Vd/Vg?75, where Vd is the volume of the depressed part and Vg is the volume of the gap.

Abstract: The present invention refers to the technical field of thermodynamic engines, and more specifically to a heat engine that operates with gas in closed loop in differential configuration which is characterized by performing a thermodynamic cycle eight transformations or otherwise explain, it performs two thermodynamic cycles simultaneously, each with four interdependent, additional transformations, two of these transformations “isothermal” and two “adiabatic” in mass transfer in phases of adiabatic processing to provide a new performance curve no longer dependent solely on temperature but the mass transfer rate which allows the construction of machines with high yields and low thermal differentials.

Abstract: A cryogenic refrigerator includes a compressor that compresses a working gas; an expansion chamber where the working gas compressed by the compressor expands and generates cooling; a valve mechanism including a stator valve and a rotor valve, which rotates with respect to the stator valve; and a forcing mechanism that applies a force to one of the rotor valve or the stator valve toward the other one of the rotor valve or the stator valve. The valve mechanism is configured to switch a flow of the working gas between the compressor and the expansion chamber as the rotor valve rotates. The forcing mechanism is arranged such that the center of the force applied by the forcing mechanism deviates from the center of the valve mechanism.

Abstract: In a Stirling refrigerator, a displacer has an internal space. An expander body houses the displacer so that the displacer can be reciprocated. A temperature sensor is arranged in the internal space of the displacer. A displacer rod, having an internal space, may connect to the displacer. A wiring may provide an electrical connection to the temperature sensor, the wiring arranged through the internal space of the displacer rod to outside of the expander body.

Abstract: A pulse tube refrigerator/cryocooler apparatus including: an inlet for receiving a cyclically moving volume of gas; a regenerator device fluidly connected to the inlet for storing and recovering thermal energy from the gas; a pulse tube fluidly connected to the regenerator; and a conduit fluidly connected at one end to the pulse tube and fluidly connected at its opposite end to a container, said container providing a storage volume for gas, wherein apparatus is configured such that the cyclically moving gas enters the regenerator in a direction parallel to its elongate axis.

Abstract: An apparatus includes an exhaust system, a cooling system, and two or more thermoacoustic devices. A first thermoacoustic device is configured to convert heat energy from the exhaust system to amplify an acoustic wave. A second thermoacoustic device configured to convert energy in the amplified acoustic wave to an input for the cooling system. The apparatus may be incorporated or in communication with an engine or a generator.

Abstract: Systems and methods for forming near net-shape metal parts from binderless metal powder are disclosed. Systems include a mold die that defines a die cavity and may include one or more ultrasonic transducers operatively coupled to the mold die. Systems may be configured to introduce binderless metal powder into a die cavity and/or to compact the binderless metal powder within the die cavity. Methods include introducing binderless metal powder into a die cavity of a mold die and compacting the binderless metal powder within the die cavity to form a green part within the die cavity. The binderless metal powder may include spheroidal metal particles and angular metal particles. The methods may further include separating the green part from the mold die and sintering the green part, after separating, to form a sintered near net-shape metal part.

Abstract: An electromagnetic motor includes a stator and an armature arranged to move substantially linearly relative to the stator in an intended direction during operation of the motor. A first and second flexure are connected to a first end of the armature. Each flexure has a longest portion which lies substantially in a plane that intersects a plane in which the armature lies at a substantially right angle. The flexures allow motion of the armature in the intended direction while resisting motion of the armature in one or more other degrees of freedom.

Abstract: [Object] To provide a hybrid system of which overall efficiency is improved. [Solution] A hybrid system of the invention includes: a fuel cell device; and a thermoacoustic cooler. The thermoacoustic cooler 14 includes: a thermoacoustic energy generating section 20 in which thermoacoustic energy is generated by a temperature gradient between a high-temperature side and a low-temperature side; and a cooling section 21 in which a function of cooling is performed in the low-temperature side using the temperature gradient between the high-temperature side and the low-temperature side which is produced when the thermoacoustic energy transmitted from the thermoacoustic energy generating section 20 is converted into energy. The system is configured to cause exhaust gas emitted from the fuel cell device to flow through the high-temperature side of the thermoacoustic energy generating section 20. Therefore, it is possible to achieve the hybrid system of which overall efficiency is improved.

Abstract: A permanent current switch device of a refrigerator cooling-type superconducting magnet includes a superconducting coil cooled by solid thermal conduction and a permanent current switch. A heat transfer member is thermally connected to a cooling stage and is structured to be inserted into and removable from a former of the permanent current switch. Due to differences in thermal expansion between the heat transfer member and the former, a permanent current mode can be stably maintained.

Abstract: A system includes a pulse tube, a compressor configured to create pulses of fluid in the pulse tube, and a surge tank. The surge tank includes a housing that defines a surge volume configured to receive the fluid from the pulse tube. An inertance channel defines a passageway through which the fluid flows to and from the surge volume. At least part of the inertance channel has an open side to the surge volume. The surge tank also includes an adjustable seal configured to block at least part of the open side of the inertance channel and to move in order to change a functional length of the inertance channel. The housing may include a material having a high coefficient of thermal expansion, and the adjustable seal may include a material having a low coefficient of thermal expansion.

Abstract: An apparatus and method is shown for determining the pumpability limit, freeze point and/or pour point of liquids, particularly fuels, at sub-ambient temperatures. A sample is placed in a viscometer which viscometer is rapidly cooled by a chiller. During cooling, after some measurements of temperature and viscosity, further temperatures and viscosity are approximated using the least squares method, which temperature and viscosity are subsequently measured to determine the pumpability limit. Continuation of the method will also give the freeze point and pour point of the sample being tested.

Abstract: The present invention relates to apparatus, systems, and methods of managing large quantities of low-grade waste heat energy by 1) generating excess electric power via an ORC process driven by the removal and recovery of waste heat under favorable operating conditions, and 2) utilizing the same apparatus to provide waste heat removal via a refrigeration process that consumes electric power when environmental conditions do not permit operation in the ORC mode. The mode of operation of the system is principally determined by the thermal energy of the waste heat stream and the availability, or lack thereof, of adequate cooling resources. Such resources are often subject to local environmental conditions, particularly ambient temperature which varies on a diurnal and annual basis.

Abstract: A disclosed cryogenic refrigerator includes a first stage displacer; a first stage cylinder configured to form a first expansion between the first stage cylinder and the first stage displacer; a second stage displacer connected to the first stage displacer; and a second stage cylinder configured to form a second expansion space between the second stage cylinder and the second stage displacer, wherein a helical groove is formed on an outer peripheral surface of the second stage displacer so as to helically extend from a side of the second expansion space toward the first stage displacer, the helical groove communicates with the first expansion space, and a cross-sectional area of the helical groove becomes smaller from a side of the second expansion space to a side of the first expansion space.

Abstract: An overvoltage protection element with a housing, an overvoltage-limiting component arranged in the housing, and with two connection elements for electrically connecting the overvoltage protection element to the current or signal path to be protected, wherein, normally, the connection elements are each in electrically conductive contact with a pole of the overvoltage-limiting component.

Abstract: A heat engine comprising compressor and expander displacement elements (210, 211) reciprocating in respective compression and expansion chambers (111, 111?, 102, 102?) and arranged in a linear, free piston configuration, a combustor (116) separate from the compression and expansion chambers (111, 111?, 102, 102?), and a linear energy conversion device (212, 213) providing conversion of solid, liquid, or gaseous fuel into hydraulic, electric, or pneumatic energy by means of subjecting a working fluid to a thermodynamic cycle with substantially constant pressure combustion. The inlet and outlet valves of the compression chamber (102, 102?) and the rate of fuel injection to the combustor (116) are actively controlled by an electronic controller to avoid engine damage, and to maintain thermodynamic efficiency over a wide range of loads.

Abstract: 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

Abstract: A heat exchanger and associated method are provided that may eliminate or reduce the need for an external mechanical or electrical power source to drive the fan by utilization, instead, of a Stirling engine. A heat exchanger includes a plurality of coils configured to carry a primary fluid. The heat exchanger also includes a fan including a plurality of fan blades configured to force a secondary fluid across the plurality of coils to facilitate heat transfer between the primary and secondary fluids. The heat exchanger also includes a Stirling engine operably connected to the fan and configured to cause rotation of the fan blades. A corresponding method is also provided.

Abstract: The present invention provides a Stirling engine capable of effectively recovering heat from exhaust gas flowing through a flue, and connecting a heating portion 10 and a regeneration portion 5 with each other through an operation gas tube without providing a flow passage separating portion 110, and the heating portion 10 includes a heating portion head 10a and a heat-transfer tube group, the heating portion head 10a includes first through holes 30R and second through holes 30S, the first through holes 30R are formed closer to a center region of the heating portion head 10a as compared with the second through holes 30S, one ends of U-shaped tubes are mounted in the first through holes 30R and the other ends of them are mounted in the second through holes 30S, and parallel exhaust gas flow passages is formed between the U-shaped tubes.