A device for controlling clearance between the tips of rotating blades of an aircraft turbomachine and a casing. An air circulation path allows air to be blown onto the casing in order to change its temperature. In addition, heating means heat the circulating air.

A steam turbine includes an outer casing (19) that is provided with a first steam outlet port (54), through which exhaust steam flowing through the entire length of a flow path (21) defined between an inner casing main body (45) and an outer casing main body (51) in a direction along an axis (O.sub.1) is discharged to the outside of the outer casing (19), and a second steam outlet port (55), which is provided in the outer casing main body (51) and through which the exhaust steam passing through a portion of the flow path (21) or the exhaust steam not passing through the flow path (21) is discharged to the outside of the outer casing (19); a first valve (28) that adjusts opening of the first steam outlet port (54); and a second valve (32) that adjusts opening of the second steam outlet port (55).

There are provided a throttle mechanism and the like that are capable of easily changing a cross-sectional area of a flow path according to an operating state. The throttle mechanism in an embodiment is a throttle mechanism that controls a flow rate of a fluid flowing through a flow path, and is configured to make a cross-sectional area of the flow path change autonomously according to temperature.

There are provided a throttle mechanism and the like that are capable of easily changing a cross-sectional area of a flow path according to an operating state. The throttle mechanism in an embodiment is a throttle mechanism that controls a flow rate of a fluid flowing through a flow path, and is configured to make a cross-sectional area of the flow path change autonomously according to temperature.

A gas turbine engine including a first turbine rotor assembly having a plurality of first turbine rotor blades extended within a gas flowpath, and a second turbine rotor assembly positioned aft along the gas flowpath of the first turbine rotor assembly. The second turbine rotor assembly is rotatably separate from the first turbine rotor assembly. A casing surrounds the first turbine rotor assembly. The casing has a unitary, integral outer casing wall extended forward of the first turbine rotor assembly and aft of the first turbine rotor assembly. The casing includes a plurality of vanes extended from the outer casing wall and through the gas flowpath aft of the first turbine rotor assembly and forward of the second turbine rotor assembly. The casing includes a plurality of walls forming thermal control rings extended outward along the radial direction from the outer casing wall. The outer casing wall and the thermal control rings is a unitary, integral structure.

An active clearance control valve (ACC Valve) includes a valve housing with a thermal shield provided externally to said housing, wherein said valve housing and said thermal shield have been integrally formed as one component. This may be achieved using additive manufacturing methods. Cooling channels and/or ribs may also be provided on or in the thermal shield.

There is provided an axial flow turbine capable of realizing a reduction in gland leakage amount. The axial flow turbine in an embodiment is of a single flow type and includes an upstream-side gland part located on an upstream side of a working medium in an axial direction of a turbine rotor and a downstream-side gland part located on a downstream side of the working medium in the axial direction of the turbine rotor. The axial flow turbine is configured such that a cooling medium lower in temperature and higher in pressure than the working medium is extracted in a middle of flowing from the inside to the outside of the turbine casing in the upstream-side gland part, and the extracted cooling medium is introduced into the stationary blade.

There is provided an axial flow turbine capable of realizing a reduction in gland leakage amount. The axial flow turbine in an embodiment is of a single flow type and includes an upstream-side gland part located on an upstream side of a working medium in an axial direction of a turbine rotor and a downstream-side gland part located on a downstream side of the working medium in the axial direction of the turbine rotor. The axial flow turbine is configured such that a cooling medium lower in temperature and higher in pressure than the working medium is extracted in a middle of flowing from the inside to the outside of the turbine casing in the upstream-side gland part, and the extracted cooling medium is introduced into the stationary blade.

A small gas turbine engine, such as is used to power a UAV, that includes at least one centrifugal compressor having an impeller with blades that form a gap between the blade tips and stationary shroud of the gas turbine engine, and where a resistance heating element is secured to or bonded to a compressor casing of the gas turbine engine in order to use heat to control the gap between the impeller blades and the stationary shroud. The resistance heating element is activated at cruise mode to move the shroud toward the impeller. Additionally or alternatively, the compressor casing is heated with bled-off compressed air to move the shroud toward the impeller. A capacitance tip clearance sensor can be mounted on the impeller shroud to monitor and control tip clearance in real time.

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 heat 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.