A compressor with negative coefficient of thermal expansion case material comprising a rotor having blades with tips, the case including an inner case comprising a negative coefficient of thermal expansion material, and a tip clearance located between the tips and the inner case; wherein the tip clearance is maintained responsive to a flow of air over the negative coefficient of thermal expansion material.

A compressor with negative coefficient of thermal expansion case material comprising a rotor having blades with tips, the case including an inner case comprising a negative coefficient of thermal expansion material, and a tip clearance located between the tips and the inner case; wherein the tip clearance is maintained responsive to a flow of air over the negative coefficient of thermal expansion material.

A gas turbine provided with: an air cooler that subjects compressed air extracted from a compressor to heat exchange and supplies the cooled compressed air to a cooling system of a rotor system in a turbine; an air cooler bypass line that bypasses the compressed air introduced into the air cooler; an electric valve provided in the air cooler bypass line; and a control unit that controls opening and closing of the electric valve such that, during activation of a gas turbine, a degree of opening of the electric valve is set at or below a low-level degree of opening and such that, after the load of the gas turbine has been increased, the degree of opening of the electric valve is set to be larger than the low-level degree of opening.

A turbine case cooling system including a turbine assembly having an inlet and an outlet and surrounded by a turbine casing. The turbine case cooling system is arranged to selectively impingement cool at least part of the turbine casing. The system includes an annular structure that is radially spaced from the turbine casing and includes a downstream end. The system includes an annular duct that is spaced radially outwardly from the turbine casing and radially inwardly from the annular structure. The duct is sealingly coupled to the turbine casing at a first end towards the turbine inlet, and a second end extends axially towards the downstream end of the annular structure and the turbine outlet.

A turbine case cooling system including a turbine assembly having an inlet and an outlet and surrounded by a turbine casing. The turbine case cooling system is arranged to selectively impingement cool at least part of the turbine casing. The system includes an annular structure that is radially spaced from the turbine casing and includes a downstream end. The system includes an annular duct that is spaced radially outwardly from the turbine casing and radially inwardly from the annular structure. The duct is sealingly coupled to the turbine casing at a first end towards the turbine inlet, and a second end extends axially towards the downstream end of the annular structure and the turbine outlet.

A passive transpirational flow acoustic liner assembly for a gas turbine engine includes a guide vane assembly and a conduit configured to deliver airflow received from the guide vane. The guide vane assembly includes an airfoil having a transpirational flow acoustic liner. The acoustic liner includes a face sheet defining a portion of an outer surface of the airfoil and having a plurality of first apertures, a segmented member coupled to the face sheet and having a plurality of chambers in fluid communication with the outer surface via the plurality of first apertures, a backing sheet having a plurality of apertures and being coupled to the segmented member such that the segmented member is positioned between the face sheet and the backing sheet, and a plenum coupled to the backing sheet opposite the segmented member and fluidly connected to the conduit.

A shroud for a gas turbine is provided. The shroud can include an outer box having a first wall and a second wall circumferentially spaced apart from the first wall. An inner box is positioned within the outer box. The inner box defines one or more passageways extending therethrough and a first chamber. The inner box and the outer box collectively define a second chamber. The one or more passageways defined by the inner box fluidly couple the first chamber and the second chamber. The first wall of the outer box defines a first boss and first notch, and the second wall of the outer box defines a second boss and notch. A gas turbine is also provided that can include a plurality of such turbine shrouds.

A gas turbine engine clearance control system includes a cooling air passage extending from a cooling air inlet port to a cooling air outlet port. The cooling air inlet port and outlet port are formed within an external surface of a compressor casing of a compressor and are also axially spaced on the external surface of the compressor casing. The cooling air passage extends from the cooling air inlet port radially inwardly to at least one of a flange joint, a radially outer surface of a compressor casing ring, and a radially outer surface of a connector case. The cooling air passage further extends aftward along the radially outer surfaces of the connector case and the compressor casing ring. The cooling air passage further extends radially outward to the cooling air outlet port. Selectively supplying cooling air to the cooling air passage controls a rotor tip clearance between a rotor tip of a rotor blade of the compressor and an inner surface of the compressor casing ring and further controls an interstage seal clearance between an inner band and a rotor spool of the compressor.

A gas turbine engine clearance control system includes a cooling air passage extending from a cooling air inlet port to a cooling air outlet port. The cooling air inlet port and outlet port are formed within an external surface of a compressor casing of a compressor and are also axially spaced on the external surface of the compressor casing. The cooling air passage extends from the cooling air inlet port radially inwardly to at least one of a flange joint, a radially outer surface of a compressor casing ring, and a radially outer surface of a connector case. The cooling air passage further extends aftward along the radially outer surfaces of the connector case and the compressor casing ring. The cooling air passage further extends radially outward to the cooling air outlet port. Selectively supplying cooling air to the cooling air passage controls a rotor tip clearance between a rotor tip of a rotor blade of the compressor and an inner surface of the compressor casing ring and further controls an interstage seal clearance between an inner band and a rotor spool of the compressor.

The invention relates to a method for measuring the flow rate of cooling air in a cooling air circuit (13) of a casing (121) of a high-pressure turbine (9) of a turbomachine (1). The invention is characterized in that sensors (21, 22, 24, 26, 28) are used to measure a total pressure at the fan inlet, a static pressure at the outlet of the high-pressure compressor (6), a rotational speed of the low-pressure shaft (101), a rotational speed of the high-pressure shaft (91) and a degree of valve opening of the cooling air circuit (13), a calculation unit is used to calculate the flow rate of cooling air on the basis of at least the measurement of these.