Abstract:
Multiple free-piston stirling-cycle machine modules are connected together in double-acting configurations that may be used as engines or heat pumps and scaled to any power level by varying the number of modules. Reciprocating piston assemblies oriented in balanced pairs reduce vibration forces. There are no buffer spaces. Linear motors or generators are packaged inside piston cavities entirely within the module working spaces. The external heat-accepting and heat-rejecting surfaces in one embodiment are directed along inward-facing and outward facing cylinders, and in another embodiment along parallel planes, simplifying thermal connections to the external heat source and sink.
Abstract:
A thermodynamic machine (1) of a Stirling type, the machine comprising an expansion chamber (5), a compression in chamber (6), a regenerator (12) disposed between the expansion and compression chambers; a first heat exchanger (13) in communication with the expansion chamber and the regenerator; a second heat exchanger (14) in communication with the compression chamber and the regenerator; a first bypass conduit (15) connecting the expansion chamber with the regenerator bypassing the first heat exchanger; a second bypass conduit (16) connecting the compression chamber with the regenerator bypassing the second heat exchanger; at least a pair valves (18, 20, 22, 24), one valve (18, 20) provided between the expansion chamber and the first heat exchanger and/or between the regenerator and the first heat exchanger and/or in the first bypass conduit between the expansion chamber and the regenerator; and the other valve (22, 24) provided between the compression chamber and the second heat exchanger and/or between the regenerator and the second heat exchanger and/or in the second bypass conduit between the compression chamber and the regenerator; the valves being controllable.
Abstract:
Aircraft with an emission-free drive and method for emission-free driving of an aircraft. The aircraft includes a drive device structured and arranged to generate thrust, a lift device structured and arranged to generate lift, and a heat engine structured and arranged to convert thermal energy into kinetic energy to drive the drive device. The heat engine includes at least one flat-plate Stirling engine drivable by solar thermal radiation.
Abstract:
A Stirling engine can take advantage of adiabatic compression (which heats working gas leaving the cold cylinder) and adiabatic expansion (which cools working gas leaving the hot cylinder) to increase efficiency. In some implementations, partially-heated gas leaving the cold cylinder and partially-cooled gas leaving the hot cylinder can be routed directly to a regenerator using bypass paths that are opened using one-way valves. The resultant relatively reduced temperature difference across the regenerator, e.g., as compared to a typical Stirling engine, can reduce thermal loss and improve efficiency. In some implementations, the compression ratios of the Stirling engine can be adjusted such that the temperature of the adiabatic heated gas is the same or higher than the temperature of the adiabatic cooled temperatures, thus eliminating the need for a regenerator.
Abstract:
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.
Abstract:
In a method for operating a reciprocating-piston internal combustion engine having internal exhaust gas energy recuperation, a cylinder head recuperator is heated up during an exhaust cycle by hot exhaust gas flowing through the cylinder head recuperator prior to being exhausted from the cylinder via an exhaust valve. During an intake cycle, fresh charge flows into the power chamber of the cylinder by passing around a cylinder head recuperator. During the subsequent compression stroke, the cylinder head recuperator is moved out of a recess formed in the cylinder head such that some of the compressed charge can flow into the recess. Near the end of the compression stroke, the cylinder head recuperator is moved back into the recess so that compressed charge located in the recess is forced to flow through the hot cylinder head recuperator and thereby be heated up immediately before ignition of the compressed charge.
Abstract:
In one embodiment, the invention relates to a heat exchanger suitable for use with a thermodynamic cycle-based machine such as an engine, an energy conversion machine, a cooling machine or other suitable systems and machines. The heat exchanger can include one or more tubes arranged to form a heat exchanger. In one embodiment, a unitary tube is used. The heat exchanger can include a canister that includes a regenerator material. The canister can be in thermal communication with a working material and a containment vessel having a containment chamber in one embodiment.
Abstract:
Aircraft with an emission-free drive and method for emission-free driving of an aircraft. The aircraft includes a drive device structured and arranged to generate thrust, a lift device structured and arranged to generate lift, and a heat engine structured and arranged to convert thermal energy into kinetic energy to drive the drive device. The heat engine includes at least one flat-plate Stirling engine drivable by solar thermal radiation.
Abstract:
A regenerator (100), for a thermal cycle engine with external combustion, according to the invention comprises a network of metal fibers wherein a majority of the fibers at least partially encircles the axis of the regenerator. The fibers were part of a fiber bundle which is coiled and sintered thereby obtaining the regenerator.
Abstract:
A combustor/recuperator assembly for use in an external combustion engine, such as a Stirling engine. The assembly includes a plurality of substantially hemispherical domed members positioned in nested uniaxial spaced relation, the plurality of substantially hemispherical domed members forming at least a first flow chamber and a second flow chamber, the first flow chamber for passing an incoming charge of air therethrough and the second flow chamber for passing an outgoing charge of combustion exhaust gases therethrough, wherein the second chamber is positioned to be effective to heat the incoming charge of air. Also provided is a system for producing power from a source of liquid fuel. The system is capable of producing up to about 5,000 watts of mechanical or electrical power.