Abstract: The present disclosure provides systems and methods wherein power production can be achieved with combustion of a fuel utilizing flameless combustion. A fuel may be combusted in a combustor/turbine in a substantially flameless operation to produce a combustion product stream that can be expanded for power generation. After expansion, the output stream can be treated to generate a recycle CO2 stream into which an oxidant can be input. The recycle CO2 stream including the oxidant can be injected into the combustor/turbine to effect combustion in a substantially flameless state. Various control schemes can be implemented to automatically control the concentration of oxygen present in the recycle CO2 stream that is injected into the combustor/turbine in order to achieve and/or maintain substantially flameless combustion.

Abstract: A Stirling engine comprising: a crank case (1) with a crank shaft (2) arranged therein, a displacer cylinder (3) with a reciprocatingly arranged displacer piston (4) therein, said displacer piston (4) being connected to said crank shaft (2) via a connecting rod (5) extending through a first end of said displacer cylinder (3), and wherein the displacer cylinder (3) defines a hot chamber (6) and a cool chamber (7) separated by the displacer piston (4), a working cylinder (8) defining a working cylinder chamber (11) with a reciprocatingly arranged working piston (9) therein, said working piston (9) being connected to said crank shaft (2) via a connecting rod (10) extending through a first end of the working cylinder (8), a heater device (14), arranged at a second end of said displacer cylinder (3) opposite to said first end and configured to heat a working gas which is present in the hot chamber (6) of the displacer cylinder (3) and in fluid communication with the working cylinder chamber (11) through a worki

Abstract: An engine apparatus, in which each piston assembly includes a piston attached to a connection member at a first end and a second end. Each piston of the piston assembly defines a first chamber and a second chamber separated by the piston. The first chamber and the second chamber are each defined at the first end and at the second end. Each first chamber of one piston assembly is fluidly connected to the second chamber at a different piston assembly. At least one first chamber at the first end is fluidly connected to a respective second chamber at the second end. At least one first chamber at the second end is fluidly connected to a respective second chamber at the first end.

Abstract: A method for actuating a semi-commanded valve that acts in synchronism with the compression cycles of an alternative compressor, and a system for actuating a multi-suction alternative compressor semi-commanded valve. The method for actuating the semi-controlled valve may involve detecting at least one compression peak in the course of at least one mechanical cycle of the alternative compressor and switching the functional status of at least an alternative compressor semi-commanded valve based on detecting at least one compression peak in the course of at least one mechanical cycle of the alternative compressor.

Abstract: A method for actuating a semi-controlled valve that acts in synchronism with the compression cycles of an alternative compressor, and a system for actuating a multi-suction alternative compressor semi-controlled valve. The method for actuating the semi-controlled valve involves detecting at least one compression peak in the course of at least one mechanical cycle of the alternative compressor and switching the functional status of at least an alternative compressor semi-controlled valve based on the detection.

Abstract: A thermoelectric vehicle system which provides a cost-effective and sustainable means of transportation for long operation range with zero emission using an onboard low energy nuclear reaction thermal generator. The present invention generally includes a thermal generator within a thermal enclosure case, an energy conversion system linked with the thermal generator, an energy storage system linked with the energy conversion system, a cooling system and a central control system. The thermal generator reacts nickel powder with hydrogen within a reactor chamber to produce heat. The heat is then transferred to the energy conversion system to be converted into electricity for storage in the energy storage system. The cooling system provides cooling for the various components of the present invention and the control system regulates its overall operation. The present invention may be utilized to power a vehicle in an efficient, sustainable and cost-effective manner.

Abstract: A monitoring system for a gas turbine includes a processor configured to receive an operating signal indicating an operating parameter of the gas turbine. The processor is configured to predict an occurrence of a lean blowout (LBO) event based on the operating parameter and an entropy ratio of combustion dynamics associated with a combustor of the gas turbine, wherein the LBO event corresponds to when the combustor stops firing. The processor is configured to send an alarm signal indicating the predicted LBO event to an electronic device prior to the occurrence of the LBO event.

Abstract: A Stirling engine includes a base member that connects a housing portion with a heater that heats a working fluid using exhaust heat of a main engine, and a support member that supports the Stirling engine at the base member is provided.

Abstract: An external-combustion, closed-cycle thermal engine is provided with: a gas chamber, a heater, and a cooler which are closed; flow paths for connecting the gas chamber and the inlet and outlet sides of the heater; flow paths for connecting the gas chamber and the inlet and outlet sides of the cooler; on-off valves respectively provided to the flow paths on the inlet and outlet sides of the heater and of the cooler; and a means for moving a working gas. The switching of the destination of the working gas between the heater and the cooler is performed by the on-off valves, and an operation body is driven. As a result of the configuration, the volume of the heater or the cooler does not affect the efficiency of the engine, and the engine operates under various conditions.

Abstract: A method and arrangement are for heat exchanging in and work exchanging with a working fluid in a heat engine, or a heat pump if the method and its sub-processes are substantially reversed.

Abstract: Systems and methods for operating a hydraulically actuated device/system are described herein. For example, systems and methods for the compression and/or expansion of gas can include at least one pressure vessel defining an interior region for retaining at least one of a volume of liquid or a volume of gas and an actuator coupled to and in fluid communication with the pressure vessel. The actuator can have a first mode of operation in which a volume of liquid disposed within the pressure vessel is moved to compress and move gas out of the pressure vessel. The actuator can have a second mode of operation in which a volume of liquid disposed within the pressure vessel is moved by an expanding gas entering the pressure vessel. The system can further include a heat transfer device configured to transfer heat to or from the at least one of a volume of liquid or a volume of gas retained by the pressure vessel.

Abstract: A thermoacoustic engine includes first and second stacks disposed in parallel in a looped tube and a heat storage unit disposed in the looped tube. A circuit length between a center of the first stack and a center of the heat storage unit is equal to a circuit length between a center of the second stack and the center of the heat storage unit. A first acoustic circuit including the first stack and the heat storage unit has a circuit length which is equal to a circuit length of a second acoustic circuit including the second stack and the heat storage unit.

Abstract: A control valve for a double acting type Stirling engine of the type having two or more piston assemblies reciprocating in bores with each of the piston assemblies separating isolated volumes of a working gas. The control valve provides the functions of a check valve which allows an internally defined volume within the engine to be held at a low pressure near the minimum pressure of the cycle volumes. The valve may further be actuated to unload the engine to provide low starting torque and to unload the engine in case of an engine or load malfunction. The control valve further provides a controlled leakage path for working fluid flowing between the cycle volumes and the minimum pressure volume which acts as part of a pressure balancing system for the Stirling engine which maintains the volume or mass of a working fluid in a balanced condition between the cycle volumes.

Abstract: A Stirling engine is provided with a fluid passage that connects a low temperature-side actuating fluid space and a crankcase inner space, and a passage opening/closing valve that is provided in the fluid passage and that opens and closes the fluid passage. Upon stopping of the Stirling engine, the passage opening/closing valve enables communication through the fluid passage, at a region at which the piston floats in the cylinder. This region is determined based on the pressure of an actuating fluid in the actuating fluid space and the rotational speed of a crankshaft of the Stirling engine.

Abstract: A thermoacoustic apparatus capable of reducing the time elapsed until an acoustic wave is generated and improving the energy conversion efficiency significantly is provided. In order to solve the above-described issues, in a thermoacoustic apparatus 1 including a pair of heat exchangers 41 and 43 separately set on the high temperature side and on the low temperature side, a second stack 42 which is sandwiched between the heat exchangers 41 and 43 and which has a plurality of transmission paths in the inside, and a loop tube 2 provided with the heat exchangers 41 and 43 and the stack 42, the thermoacoustic apparatus converting acoustic energy generated in the loop tube 2 with an acoustic wave generator 3 to thermal energy by using the heat exchangers 41 and 43 and the stack 42, a narrow portion 21 in which the inner diameter is relatively reduced is disposed at a position at which the particle velocity of a standing wave generated in the loop tube 2 is in the vicinity of a maximum.

Abstract: An annular burner assembly having an annular burner mesh. An annular gas/air supply duct supplies a combustible gas/air mixture to the burner mesh in a substantially axial direction. A flow modifier is provided in the vicinity of the burner and has a plurality of fins each extending in a substantially radial plane to define a plurality of passages arranged circumferentially around the supply duct to substantially laminarise the gas/air mixture. The fins provide a thermal link from the burner to a location radially away from the burner. The burner assembly is particularly suited to a Stirling engine.

Abstract: A thermodynamic cycle heat engine including a regenerator; a chamber in fluid communication with the regenerator; first and second rotors within the chamber, forming at least a pair of spaces within the chamber; and at least one actuator. The regenerator and the chamber form a portion of a closed space for a working fluid, the actuator is arranged to displace the rotors about an axis of rotation for the rotors, and at least a portion of the actuator is fixedly secured to the rotors. In some aspects, the actuator is arranged to receive energy from the rotors and operate as a generator, or a sensor is arranged to detect a condition associated with operation of the chamber and a controller is arranged to control the actuator responsive to the detected condition. In some aspects, the engine includes a heat exchanger in fluid communication between the regenerator and the chamber.

Abstract: In a Stirling engine, a casing houses therein component elements of the Stirling engine, including a high-temperature-side cylinder, a high-temperature-side piston, a connecting rod, a crankshaft, etc. A pressure control device determines whether the pressure of the gas charged in the casing has declined. If the pressure of the gas has declined, the pressure control device drives a pump to pressurize the gas charged in the casing.

Abstract: Systems and methods for operating a thermodynamic engine are disclosed. The systems and methods may effect cyclic motion of a working fluid between hot and cold regions of a thermodynamic engine and inject a dispersible material into the working fluid at the hot or cold region during a heat-addition or heat-rejection process. The system and methods may also evacuate the dispersible material from the hot or cold region.

Abstract: An external combustion engine having an exhaust flow diverter for directing the flow of an exhaust gas. The external combustion engine has a heater head having a plurality of heater tubes through which a working fluid is heated by conduction. The exhaust flow diverter is a cylinder disposed around the outside of the plurality of heater tubes and includes a plurality of openings through which the flow of exhaust gas may pas. The exhaust flow diverter directs the exhaust gas past the plurality of heater tubes. The external combustion engine may also include a plurality of flow diverter fins coupled to the plurality of heater tubes to direct the flow of the exhaust gas. The heater tubes may be U-shaped or helical coupled shaped.

Abstract: A stirling engine includes a flow path that communicates a working space of the stirling engine and outside of the stirling engine. A working gas is supplied from the outside of the stirling engine to the working space via the flow path based on a differential pressure of the working space and the outside of the stirling engine.

Abstract: Embodiments for an apparatus and associated method for reducing the residence time in a gas turbine combustor are disclosed. The embodiments of the present invention comprise a fuel nozzle that extends to a downstream plane of an end cap for a combustion liner where the axial distance of the premixer is reduced, however the swirl for mixing the fuel and air, is increased. As a result, the mixing of the fuel and air is essentially unchanged, thereby allowing higher air pressures and operating temperatures within the premixer without inducing auto-ignition.

Abstract: This invention relates to a method of operating an engine and, particularly to a method of determining the pressure of a working gas within a Stirling engine of a domestic combined heat and power unit relative to a pre-defined pressure. The present invention provides a method of determining the pressure of a gas within an engine relative to a pre-defined pressure of the gas, comprising measuring the power factor of electricity generated by the engine, comparing the measured power factor with a power factor determined to correspond to the power factor of electricity generated by the engine when operating at the pre-defined pressure and determining whether the measured power factor is less than the determined power factor. Variations in measured power factors may also be used to indicate faults in the engine.

Abstract: An external combustion engine having an exhaust flow diverter for directing the flow of an exhaust gas. The external combustion engine has a heater head having a plurality of heater tubes through which a working fluid is heated by conduction. The exhaust flow diverter is a cylinder disposed around the outside of the plurality of heater tubes and includes a plurality of openings through which the flow of exhaust gas may pas. The exhaust flow diverter directs the exhaust gas past the plurality of heater tubes. The external combustion engine may also include a plurality of flow diverter fins coupled to the plurality of heater tubes to direct the flow of the exhaust gas. The heater tubes may be U-shaped or helical coiled shaped.

Abstract: A channelized stratified regenerator with integrated heat exchangers are disclosed using micromachining to precisely construct structural geometries, such as fins and axial stratification of material to be used in a Stirling cycle based system. In operation, a working fluid passes through the regenerator when traveling between two heat exchangers. In some implementations, the regenerator and the heat exchangers are formed as a single construction. In other implementations, the regenerator and heat exchangers are formed separately, but are constructed to integrate efficiently with one another.

Abstract: A channelized stratified regenerator with integrated heat exchangers are disclosed using micromachining to precisely construct structural geometries, such as fins and axial stratification of material to be used in a Stirling cycle based system. In operation, a working fluid passes through the regenerator when traveling between two heat exchangers. In some implementations, the regenerator and the heat exchangers are formed as a single construction. In other implementations, the regenerator and heat exchangers are formed separately, but are constructed to integrate efficiently with one another.

Abstract: An electromechanical compression release valve for compressors, engines with rotary or reciprocating mechanisms and external combustion engines, such as, a Stirling cycle engine, reduces the engine starting power by reducing the compression pressure in the cylinder head space area. The valve reduces the compression pressure by passing the working fluid from the cylinder head space to another compartment. The valve comprises a housing, a valve member, a valve-driving member, a valve position sensor, and a ratchet pawl. In the open position, and while starting the engine, the inlet of the rotatable valve member is aligned with the opening in a chamber connected to the engine work space, thus, the working fluid passes through the valve member into the crankcase. After the engine starts, the valve position sensor directs the valve-driving member to rotate the valve member to the closed position. When closed, the engine working fluid can now achieve the operating compression pressures.

Abstract: A rotary Stirling-type engine (100) having a heat chamber (105) with a compressing turbine (107) at one end and a valve assembly (108) through which gas enters the heat chamber (105). At the order end is a nozzle housing (109) for gas exit. A shaft (110) extends from the turbine (107) and is mounted in a bearing (111). Another shaft (112) extends from the nozzle housing (109), mounted in bearing (113). A rotor flywheel (114) is also mounted on shaft (110) and fixed in place by socket pin (115). The engine also contains insulating jacket (120), regenerating a housing (122) and a heat sink (126). In the engine, gas is compressed by the turbine (107) until it opens valve (108). The passes through and expands in the heat chamber where it receives heat radiation (eg. Solar) through a glass window (121). The gas cannot escape back through the valve (108) but rather through two circumferentially mounted nozzle adjusters, spinning the whole central assembly, including the compressing turbine (107), as it escapes.

Abstract: A DCHP unit with a Stirling engine (1), a burner (3) and a supplementary burner (11). Water is heated by exhaust gas from the Stirling engine and from the supplementary burner. If a sensor (18) detects that the water temperature has risen indicating that there is insufficient demand for the heat in the exhaust gas, a fan (15), (20) which normally provides the flow of air to the supplementary burner is operated without firing the burner to generate a flow of cool air to cool the water.

Abstract: An external combustion engine having an exhaust flow diverter for directing the flow of an exhaust gas. The external combustion engine has a heater head having a plurality of heater tubes through which a working fluid is heated by conduction. The exhaust flow diverter is a cylinder disposed around the outside of the plurality of heater tubes and includes a plurality of openings through which the flow of exhaust gas may pas. The exhaust flow diverter directs the exhaust gas past the plurality of heater tubes. The external combustion engine may also include a plurality of flow diverter fins coupled to the plurality of heater tubes to direct the flow of the exhaust gas. The heater tubes may be U-shaped or helical coiled shaped.

Abstract: A hydrogen production system for use in connection with Stirling engines. The production system generates hydrogen working gas and periodically supplies it to the Stirling engine as its working fluid in instances where loss of such working fluid occurs through usage through operation of the associated Stirling engine. The hydrogen gas may be generated by various techniques including electrolysis and stored by various means including the use of a metal hydride absorbing material. By controlling the temperature of the absorbing material, the stored hydrogen gas may be provided to the Stirling engine as needed.

Abstract: A hydrogen production system for use in connection with Stirling engines. The production system generates hydrogen working gas and periodically supplies it to the Stirling engine as its working fluid in instances where loss of such working fluid occurs through usage through operation of the associated Stirling engine. The hydrogen gas may be generated by various techniques including electrolysis and stored by various means including the use of a metal hydride absorbing material. By controlling the temperature of the absorbing material, the stored hydrogen gas may be provided to the Stirling engine as needed.

Abstract: A method for controlling the fuel-air ratio of a burner having a blower responsive to a blower drive signal for injecting air into the burner. The method is based at least on the concentration of a gas in an exhaust gas product of a combustion chamber of the burner and includes measuring the gas concentration in the exhaust gas product, deriving a gas concentration signal from the measured gas concentration, determining the fuel-air ratio from the gas concentration signal and the sign of the derivative of the gas concentration signal with respect to the blower drive signal, and controlling the fuel-air ratio by adjusting the air flow rate into the burner. The burner may be, for example, in a Stirling cycle engine.

Abstract: A heat pumping machine, such as used for home heating and cooling, has a free piston Stirling engine driving a vapor compression heat pump. The engine is mechanically linked to the compressor inside a common hermetically sealed enclosure. A fluid conducting passage connects the refrigerant flow path in communication with a working gas space in the Stirling engine. Although carbon dioxide may be used in both as the refrigerant and the engine working gas, preferably both helium and carbon dioxide are used and separated by a phase separator so that helium rich gas is directed into the Stirling engine and carbon dioxide rich fluid is directed through the heat pump.

Abstract: An external combustion engine having an exhaust flow diverter for directing the flow of an exhaust gas. The external combustion engine has a heater head having a plurality of heater tubes through which a working fluid is heated by conduction. The exhaust flow diverter is a cylinder disposed around the outside of the plurality of heater tubes and includes a plurality of openings through which the flow of exhaust gas may pas. The exhaust flow diverter directs the exhaust gas past the plurality of heater tubes. The external combustion engine may also include a plurality of flow diverter fins coupled to the plurality of heater tubes to direct the flow of the exhaust gas. The heater tubes may be U-shaped or helical coiled shaped.

Abstract: A heating and refrigerating machine, especially a Vuilleumier heat pump or Stirling engine, in which a gas-air mixture is combusted in a combustion chamber and the exhaust gas radiates thermal energy to a heater head, which functions as a housing for the hot piston of the machine, part of the outer surface of the heater head forming a portion of the combustion chamber. By using a porous-medium burner and by virtue of its adaptation to the heater head, the transmission of heat by convection and radiation is improved and a compact machine design is attained which transmits heat in a highly efficient manner with low emissions over a broad output modulation range.

Abstract: A method of combusting fuel and air in a burner of an external combustion engine having a heater head. The fuel and air are combined to form a fuel-air mixture which is characterized by a fuel-air ratio. An exhaust gas product is produced when the fuel-air mixture is combusted in the burner of the external combustion engine. A flame is formed by igniting the fuel-air mixture at a first fuel-air ratio produced by a first air flow rate and a fuel flow rate. The air flow rate is then increased to produce a second fuel-air ratio. The fuel flow rate is also controlled based upon a temperature of the heater head of the external combustion engine. The flame is maintained at the second fuel-air ratio by adjusting the air flow rate based on the fuel flow rate. The external combustion engine may be, for example, a Stirling cycle engine.

Abstract: A traveling-wave device is provided with the conventional moving pistons eliminated. Acoustic energy circulates in a direction through a fluid within a torus. A side branch may be connected to the torus for transferring acoustic energy into or out of the torus. A regenerator is located in the torus with a first heat exchanger located on a first side of the regenerator downstream of the regenerator relative to the direction of the circulating acoustic energy; and a second heat exchanger located on an upstream side of the regenerator. The improvement is a mass flux suppressor located in the torus to minimize time-averaged mass flux of the fluid. In one embodiment, the device further includes a thermal buffer column in the torus to thermally isolate the heat exchanger that is at the operating temperature of the device.

Abstract: A hermetically sealed Stirling engine driven generator system with a rotating generator, self lubricated bearings using PTFE filled polyimide, a fibrous ceramic piston dome, and flame sprayed ceramic and PTFE coating on the pistons, which allow an oil free system. A brushless self starting system is also used as an alternator. A simple working gas pressure control system uses the housing for the generator and the crankcase as a reservoir for working gas allowing a single valve working in conjunction with a small compressor to regulate the pressure of the working gas.

Abstract: An improved pressure control apparatus for a stirling module capable of controlling a pressure between compression space and a bounce space by providing an improved pressure control apparatus, so that a high speed operation of a stirling module can be obtained, which includes a piston including a plurality of pressure control hole groups vertically extended within the piston for connecting between the compression space and the bounce space, each of groups consists of at least one hole; a pressure control member supporting section having a diameter smaller than that of the piston and upwardly extended from the top of the piston; a support member engaging section having a diameter smaller than that of the pressure control member supporting section and upwardly extended from the top of the support member engaging section; and a pressure control member including an engaging section threadly engaged to the pressure control member supporting section and an opening/closing section having a plurality of wings.

Abstract: A Stirling engine generating system comprises a Stirling engine driven by solar heat which is used as a heat input source for the engine, a generator driven by the Stirling engine, a temperature sensor detecting the temperature of an operational gas enclosed in an operational space of the engine, an operational gas tank communicated with the operational space via a pair of conduits, one way valves interposed in the corresponding conduits so as to invert the flow direction of the operational gas in each conduit, opening and closing valves each of which is interposed in the respective conduit between the one way valve and the operational gas tank, a field magnet control device for adjusting the rotational speed of the generator and a temperature regulation device for controlling the opening and closing action of the opening and closing valves to vary the operational gas pressure in the operational space in response to a detected signal of the temperature sensor and for controlling the field magnet control devic

Abstract: There is disclosed an apparatus for controlling the rotational speed of a Stirling engine in such a way that effective use is made of dump power produced when the speed of the engine is maintained constant. The apparatus comprises a tank in which a working medium is stored, a first valve mechanism, a second valve mechanism, a dynamo for producing alternating current during operation of the engine, a load to which the alternating current is applied, an accessary receiving the alternating current via a distributor, and a control unit. When a change in the electric power consumed by the load is detected, the control unit actuates the first or second valve mechanism to force the working medium out of the tank into the working space in the engine or vice versa such that the speed of the engine corresponds to the change in the electric power. When the engine speed increases, the resulting increase in the electric power is consumed for the accessary such as a cooling fan or a battery that powers the starter.

Abstract: The invention relates to an apparatus for mean pressure control of a Stirling engine without the need for a compressor. The invention includes a multi-tank system in which there is at least one high pressure level tank and one low pressure level tank wherein gas flows through a maximum pressure and supply line from the engine to the high pressure tank when a first valve is opened until the maximum pressure of the engine drops below that of the high pressure tank opening an inlet regulator to permit gas flow from the engine to the low pressure tank. When gas flows toward the engine it flows through the minimum pressure supply line 2 when a second valve is opened from the low pressure tank until the tank reaches the engine's minimum pressure level at which time the outlet regulator opens permitting gas to be supplied from the high pressure tank to the engine. Check valves between the two tanks prevent any backflow of gas from occurring.

Abstract: A Stirling engine includes a heater device for collecting solar radiation energy, a heater tube disposed in the heater device and connecting the expansion space and the compression space of cylinder containing a piston, and a transparent partition located in the heater device for defining a closed space. A heat storage material is positioned in the closed space and a temperature detecting apparatus is provided for detecting the temperature of the heat storage material. A pressure regulating arrangement regulates the pressure of a working gas in a working space located between the expansion space and the compression space of the cylinder. A control device controls the pressure regulating arrangement in response to a signal from the temperature detecting apparatus.

Abstract: A Stirling engine in which a working space is communicated with a working gas tank through a minimum cycle pressure line having an accelerating valve and a one-way valve and a maximum cycle pressure line having a decelerating valve and a one-way valve is provided with a starting apparatus including a bypass valve provided between the two pressure lines. When the engine is to be started, the bypass valve is opened and a starting motor is set into operation. The bypass valve is closed immediately after the Stirling engine starts, thus enabling the engine to quickly begin operating in a self-supporting manner.

Abstract: A Stirling engine control apparatus includes a pressure reducing valve provided in a maximum cycle pressure line connecting a working space to a working gas compressor via a first check valve, a pressure boost valve provided in a minimum cycle pressure line connecting the working space to the working gas compressor via a second check valve, an operating lever pivotable about a movable fulcrum for controlling opening and closing of the pressure reducing valve and the pressure boost valve, an electronic control circuit for driving a motor adapted to move the pivot point, and an unload valve provided in a line shorting intake and discharge sides of the compressor.

Abstract: Described is a working gas pressure control apparatus for a Stirling engine including a pressure boost valve provided in a minimum cycle pressure line connected to a working space by a first unidirectional valve, a pressure reducing valve provided in a maximum cycle pressure line connected to the working space by a second unidirectional valve, an operating lever for controlling the opening and closing of the pressure boost and pressure reducing valves, a compressor connected by the pressure reducing and the pressure boost valve to the cycle pressure lines, an unloading valve arranged in a circuit short-circuiting suction and discharge lines of the compressor, and a control unit for opening the unloading valve when engine rpm falls to a value lower than a preset rpm for engine idling, when the pressure boost valve is open and when the engine is operating in the steady state, thereby minimizing compressor load.

Abstract: A Stirling engine control apparatus includes a pressure reducing valve provided in a maximum cycle pressure line connecting a working space to a working gas compressor and a working gas tank via a first check valve, a pressure boost valve provided in a minimum cycle pressure line connecting the working space to the working gas storage tank via a second check valve, an operating lever pivotable about a movable fulcrum for controlling opening and closing of the pressure reducing valve and the pressure boost valve, a movable member on which the movable fulcrum of the operating lever is provided, and control means for positionally shifting the movable member upon comparing a target pressure corresponding to displacement of the operating lever and pressure within the minimum cycle pressure line.

Abstract: A two-tank working gas supply and pump-down system is coupled to a hot gas engine, such as a Stirling engine. The system has a power control valve for admitting the working gas to the engine when increased power is needed, and for releasing the working gas from the engine when engine power is to be decreased. A compressor pumps the working gas that is released from the engine. Two storage vessels or tanks are provided, one for storing the working gas at a modest pressure (i.e., half maximum pressure), and another for storing the working gas at a higher pressure (i.e., about full engine pressure). Solenoid valves are associated with the gas line to each of the storage vessels, and are selectively actuated to couple the vessels one at a time to the compressor during pumpdown to fill the high-pressure vessel with working gas at high pressure and then to fill the low-pressure vessel with the gas at low pressure.

Abstract: The invention relates to a power control system for a hot gas engine in which the power depends on the mean working gas pressure in the engine. Said engine is of the type having an even number of working gas charges separated by pistons each having two axially displaced piston rings. Said piston rings and their piston ring grooves are shaped to act as check valves and so that in each other piston the space between the piston rings will contain gas of maximum working cycle pressure whereas in the remaining pistons it will be minimum working cycle pressure.