Abstract:
The present disclosure is directed to an aircraft power generation system including a reverse Brayton cycle system, a gas turbine engine, and a gearbox. The gas turbine engine includes a compressor section, a turbine section, and an engine shaft. The compressor section is arranged in serial flow arrangement with the turbine section. The engine shaft is rotatable with at least a portion of the compressor section and with at least a portion of the turbine section. The reverse Brayton cycle system includes a compressor, a driveshaft, a turbine, and a first exchanger. The driveshaft is rotatable with the compressor or the turbine, and the compressor, the first heat exchanger, and the turbine are in serial flow arrangement. The gearbox is configured to receive mechanical energy from the engine shaft and transmit mechanical energy to the reverse Brayton cycle system through the driveshaft.
Abstract:
Ein Wärmepumpensystem umfasst folgende Merkmale: eine erste Wärmepumpenanordnung (111), die einen Verdichter (112) mit einem Verdichterausgang (113) aufweist; eine zweite Wärmepumpenanordnung (114), die einen Eingangsabschnitt (114a) und einen Ausgangsabschnitt (114b) aufweist; und einen Koppler (115) zum thermischen Koppeln der ersten Wärmepumpenanordnung (111) und der zweiten Wärmepumpenanordnung (114), wobei der Koppler (115) einen ersten Wärmetauscher (115a) und einen zweiten Wärmetauscher (115b) aufweist, wobei der erste Wärmetauscher (115a) mit dem Eingangsabschnitt (114a) der zweiten Wärmepumpenanordnung (114) verbunden ist, und wobei der zweite Wärmetauscher (115b) mit dem Ausgangsabschnitt (114b) der zweiten Wärmepumpenanordnung (114) verbunden ist.
Abstract:
When cooling a superconducting magnet for use in a magnetic resonance imaging (MRI) device, a two-stage cryocooler (42) employs a first stage cooler (52) to cool a working gas (e.g., Helium, Hydrogen, etc.) to approximately 25 K. The working gas moves through a tubing system by convection until the magnet (20) is at approximately 25K. Once the magnet (20) reaches 25 K, gas flow stops, and a second stage cooler (54) cools the magnet (20) further, to about 4 K.
Abstract:
A cryogenic refrigerator has a refrigeration cylinder and at least two displacers. Each displacer reciprocates in the refrigeration cylinder and moves refrigeration gas through the refrigeration cylinder. A regenerator cools the refrigeration gas, and gas control valves admit high pressure gas into the refrigeration cylinder and exhaust gas from the refrigeration cylinder. The refrigerator also has linear motors operatively connected to displacers, and the linear motors drive the displacers in reciprocating movement. A position sensor is provided to determine a parameter of the displacers during reciprocation. A controller is operatively connected to the linear motors to control the linear motors. The controller controls a parameter of the two displacers during reciprocation. The parameter can be stroke length, stroke speed, stroke phase or another parameter of the displacer for temperature control of the cryogenic refrigerator. The cryogenic refrigerator may also include a device to remove vibration.
Abstract:
The present invention describes a method and apparatus for controlling the operating pressure of a Reverse Brayton type refrigeration device 70 for the purposes of regulating cooling capacity and coolant inventory control.
Abstract:
A cryocooler system having at least one flow straightener (36, 37, 56, 57, 5) which has a system of grooves (3, 4) on its perforated surface for enhancing gas flow uniformity through the system wherein pulsing gas which does not initially pass through the flow straightener through a perforation flows along the surface of the flow straightener within a groove prior to passing through a perforation and is effectively redistributed across the surface of the flow straightener and thus the cross section of the regenerator (30) or thermal buffer tube (50).
Abstract:
A multi-stage cryocooler (100) includes a concentric second-stage pulse tube expander (130) in which a pulse tube (132) is located within a second-stage regenerator (131). In one embodiment, an inner wall of the regenerator also functions as an outer wall of the pulse tube. In another embodiment, there is an annular gap between an inner wall of the regenerator and an outer wall of the pulse tube. The gap may be maintained at a low pressure, approaching a vacuum, by placing the gap in fluid communication with an environment around the cryocooler, such as the low-pressure environment of space. The integrated second-stage structure, with the pulse tube within the annular regenerator, provides several potential advantages over prior multi-stage cryocooler systems.