Sealing ring (36, 38) for a wheel (26) of an aircraft turbomachine turbine, said ring comprising an annular body (51) extending around an axis of revolution (A) and comprising an outer surface (51a) and an inner surface (51b) which is coated with an annular layer (53) of an abradable material, the ring further comprising an annular wall (52) extending around the annular body and at a radial distance from said body, said annular wall comprising openings (54) through which cooling air flows by impact on the outer surface, characterised in that the body and the wall are integrally formed.

Sealing ring (36, 38) for a wheel (26) of an aircraft turbomachine turbine, said ring comprising an annular body (51) extending around an axis of revolution (A) and comprising an outer surface (51a) and an inner surface (51b) which is coated with an annular layer (53) of an abradable material, the ring further comprising an annular wall (52) extending around the annular body and at a radial distance from said body, said annular wall comprising openings (54) through which cooling air flows by impact on the outer surface, characterised in that the body and the wall are integrally formed.

A component for a gas turbine engine. The component includes a body. The body has an exterior surface abutting a flowpath for the flow of a hot combustion gas through the gas turbine engine. Further, the body defines a cooling passageway within the body to supply cool air to the component. The component includes a leading face and a trailing face defining a trench therebetween on the exterior surface. The body defines a plurality of cooling holes extending between the cooling passageway and a plurality of outlets defined in the trench such that the trench is fluidly coupled to the cooling passageway. Additionally, the leading face and trailing face are each tangent to at least one of the plurality of outlets. The trench directs the cool air along a contour of the component.

A component for a gas turbine engine. The component includes a body. The body has an exterior surface abutting a flowpath for the flow of a hot combustion gas through the gas turbine engine. Further, the body defines a cooling passageway within the body to supply cool air to the component. The component includes a leading face and a trailing face defining a trench therebetween on the exterior surface. The body defines a plurality of cooling holes extending between the cooling passageway and a plurality of outlets defined in the trench such that the trench is fluidly coupled to the cooling passageway. Additionally, the leading face and trailing face are each tangent to at least one of the plurality of outlets. The trench directs the cool air along a contour of the component.

A gas turbine engine has: a first component and a second component defining a respective first gaspath surface and a second gaspath surface of an annular gaspath, the first and second gaspath surfaces axially spaced apart from one another by an annular recess in the first component; a bushing ring disposed within the annular recess and defining stem pockets therein; variable guide vanes pivotable about respective vane axes extending between first and second stems; and a biasing member received within the annular recess and disposed axially between the bushing ring and one of the first component and the second component, the biasing member exerting a force against the bushing ring in an axial direction relative to the central axis and towards the other of the first component and the second component.

A gas turbine engine has: a first component and a second component defining a respective first gaspath surface and a second gaspath surface of an annular gaspath, the first and second gaspath surfaces axially spaced apart from one another by an annular recess in the first component; a bushing ring disposed within the annular recess and defining stem pockets therein; variable guide vanes pivotable about respective vane axes extending between first and second stems; and a biasing member received within the annular recess and disposed axially between the bushing ring and one of the first component and the second component, the biasing member exerting a force against the bushing ring in an axial direction relative to the central axis and towards the other of the first component and the second component.

A gas turbine engine for an aircraft includes an engine core including a first, lower pressure, turbine, a first compressor, and a first core shaft connecting the first turbine to the first compressor; and a second, higher pressure, turbine, a second compressor, and a second core shaft connecting the second turbine to the second compressor, and a fan located upstream of the engine core and including a plurality of fan blades extending from a hub. A turbine to fan tip temperature change ratio of a low pressure turbine temperature change to a fan tip temperature rise is in the range from 1.46 to 2.0.

A gas turbine engine for an aircraft includes an engine core including a first, lower pressure, turbine, a first compressor, and a first core shaft connecting the first turbine to the first compressor; and a second, higher pressure, turbine, a second compressor, and a second core shaft connecting the second turbine to the second compressor, and a fan located upstream of the engine core and including a plurality of fan blades extending from a hub. A turbine to fan tip temperature change ratio of a low pressure turbine temperature change to a fan tip temperature rise is in the range from 1.46 to 2.0.

A blade tip measurement system includes a case and a blade that rotates within the case, the blade having an outer blade tip surface that has a clearance distance from an inner surface of the case. A light source emits light along an optical path that is directed toward the outer blade tip surface by a lens, and the outer blade tip surface reflects the light back along the optical path. An optical interferometer generates an interference pattern using the reflected light, and a photoreceiver receives the interference pattern. A complex logic device determines the clearance distance of the blade tip surface from the inner surface of the case based on the interference pattern. The interferometer may be a Fabry-Perot optical interferometer formed using a window positioned between the lens and the blade tip surface, or a Michelson interferometer formed using a reference optical path. The system may alternatively include an optical time of flight measurement of the blade tip clearance. The system further may include an abradable substrate having an optical fiber array of optical fibers at different depths, whereby the blade tip clearance is determinable based on which of the optical fibers are abraded as the blade tip rotates.

A method for reducing an engine core speed is disclosed, which includes determining a condition of an engine during operation of the engine, and controlling an engine turbine clearance based on the condition of the engine so as to influence the engine core speed. An engine system comprising an engine core speed reducing system is also disclosed.