A steam turbine has a diffuser that is configured to guide steam to an outside of a casing. The diffuser has an outer guide that gradually expands to an outer side in a radial direction and an inner guide that is disposed at intervals to an inner side in the radial direction with respect to the outer guide. The inner guide has an inner curved diameter-expanded portion that gradually expands to the outer side in the radial direction while being curved from the first side to the second side in the axial direction. The outer guide has a first diameter-expanded portion that gradually expands to the outer side in the radial direction with a first radius of curvature, and a second diameter-expanded portion that gradually expands to the outer side in the radial direction with a second radius of curvature larger than the first radius of curvature.

An airfoil assembly includes first and second fiber-reinforced composite airfoil rings that each have inner and outer platform sections, a suction side wall extending between the inner and outer platforms, a pressure side wall extending between the inner and outer platforms, and suction and pressure side mate faces along, respectively, edges of the suction and pressure side walls. The suction side mate face of the first fiber-reinforced composite airfoil ring and the pressure side mate face of the second fiber-reinforced composite airfoil ring mate at an interface to form an airfoil that circumscribes an internal cavity. A least one of the suction or pressure side mate faces includes protrusions along a trailing edge of the airfoil. The protrusions define a toothed exit slot for emitting cooling air from the internal cavity.

A gas turbine engine includes: a fan rotating about an engine main axis; a core duct; an engine core; an Engine Section Stator (ESS) including a plurality of ESS vanes and arranged in the core duct downstream of the fan; and a plurality of variable inlet guide vanes (VIGV) adapted to rotate about a pivot axis and arranged in the core duct downstream of the ESS. The VIGV vanes are arranged angularly rotated with respect to the ESS vanes such that the VIGVs are shielded by the ESS, thereby protecting the VIGVs from icing and from ice shedding from the ESS vanes.

A gas turbine engine includes: a fan rotating about an engine main axis; a core duct; an engine core; an Engine Section Stator (ESS) including a plurality of ESS vanes and arranged in the core duct downstream of the fan; and a plurality of variable inlet guide vanes (VIGV) adapted to rotate about a pivot axis and arranged in the core duct downstream of the ESS. The VIGV vanes are arranged angularly rotated with respect to the ESS vanes such that the VIGVs are shielded by the ESS, thereby protecting the VIGVs from icing and from ice shedding from the ESS vanes.

A gas turbine engine includes a fan rotor driven by a fan drive turbine about an axis through a gear reduction. An inner core engine has an inner core engine housing surrounding a compressor section, including a low pressure compressor. A rigid connection between a fan case and the inner core engine includes A-frames rigidly connected at a connection point to the fan case. Fan exit guide vanes rigidly connect to the fan case, and to the inner core engine. A fan intermediate case is positioned forward of a first rotor stage in the low pressure compressor. A rigid structure is connected to the inner core engine and to the fan exit guide vanes. The rigid structure defines a structure moment stiffness. The fan intermediate case defines an intermediate case moment stiffness. A ratio of the structure moment stiffness to the intermediate case moment stiffness is between 5 and 15.

A gas turbine has blades. A blade may have a leading edge; a trailing edge; a pressure side and a suction side, which extend between the leading edge and the trailing edge. The blade has, along the leading edge, a leading edge profile with profile portions, each of which, along its profile portion length, transitioning, proceeding from a depression, into an elevation via a first transition portion and back into a next depression via a second transition portion. An apex of the elevation of a profile portion is arranged in an asymmetric manner in relation to the profile portion length, in such a way that the first transition portion has a first transition length and the second transition portion has a second transition length. The first transition length and the second transition length are different lengths.

A gas turbine has blades. A blade may have a leading edge; a trailing edge; a pressure side and a suction side, which extend between the leading edge and the trailing edge. The blade has, along the leading edge, a leading edge profile with profile portions, each of which, along its profile portion length, transitioning, proceeding from a depression, into an elevation via a first transition portion and back into a next depression via a second transition portion. An apex of the elevation of a profile portion is arranged in an asymmetric manner in relation to the profile portion length, in such a way that the first transition portion has a first transition length and the second transition portion has a second transition length. The first transition length and the second transition length are different lengths.

A gas turbine has blades. A blade may have a leading edge; a trailing edge; a pressure side and a suction side, which extend between the leading edge and the trailing edge. The blade has, along the leading edge, a leading edge profile with profile portions, each of which, along its profile portion length, transitioning, proceeding from a depression, into an elevation via a first transition portion and back into a next depression via a second transition portion. An apex of the elevation of a profile portion is arranged in an asymmetric manner in relation to the profile portion length, in such a way that the first transition portion has a first transition length and the second transition portion has a second transition length. The first transition length and the second transition length are different lengths.

A variable capacity turbocharger includes: a nozzle flow path which allows a gas to pass from a scroll flow path toward a turbine impeller; a shroud side ring and a hub side ring which face each other in a rotation axis direction of the turbine impeller and form a nozzle flow path therebetween; a bearing hole which is provided in the shroud side ring; a bearing hole which is provided in the hub side ring; and a nozzle vane which is disposed in the nozzle flow path and is supported by both bearing holes, wherein a center axis line of the bearing hole is located on the inside in a radial direction in relation to a center axis line of the bearing hole at a room temperature and the center axis line is located on the outside in the radial direction in relation to the center axis line when a predetermined temperature difference is generated between the shroud side ring and the hub side ring during operation.

A turbine for a turbo-machine is proposed in which, at a gas inlet for a turbine wheel, vanes extend from a nozzle ring though slots in a shroud. The nozzle ring and shroud are relatively rotatable about a rotational axis of the turbine by at least 0.1 degrees. In use, the nozzle ring and shroud are relatively rotated to bring one side of the vane into close contact with one surface of the slot, to inhibit leakage of gas between the vane and the slot surface. For this purpose the respective surfaces of the nozzle and slot can be configured to closely conform to each other. If there is differential thermal expansion of the shroud and nozzle ring, the nozzle ring and shroud can relatively rotate, to withdraw the vane from the edge of the slot to relieve the pressure between them.