An air turbine starter having a housing, a turbine, a drive shaft, and at least one vane. The housing having an inlet, an outlet and a curvilinear flow path extending between the inlet and the outlet. The at last one vane is located within a portion of the curvilinear flow path, and includes an outer wall extending between a root and a tip in a span-wise direction and between a leading edge and a trailing edge in a chord-wise direction. In one aspect, the vane is arranged to define an acute axial angle that is non-constant in the chord-wise or span-wise direction. In another aspect, the vane is arranged to define an acute tangential angle that is non-constant in the chord-wise or span-wise direction.

An impeller includes Z blades, where Z is an integer equal to 5 or more, arranged in a circumferential direction of the impeller and extending radially, pitch angles between adjacent blades being all different. In terms of an arbitrary pitch angle θ, when a pitch angle α1 adjacent to the pitch angle θ, and a pitch angle α2 adjacent to the pitch angle θ, different from the pitch angle α1, satisfy a relation, α1<α2, a pitch angle β1 different from the pitch angle θ adjacent to the pitch angle α1 and a pitch angle β2 adjacent to the pitch angle β2, different from the pitch angle θ, satisfy a relation, β2<β1.

A part or an assembly of parts of a splitter stage of a turbofan, including a plurality of obstacles including at least one a blade and at least one arm, and a platform from which the obstacles extend, wherein the arm is defined by a skeleton angle having a trailing value on the trailing edge of between 3° and 15°.

A guide vane airfoil for placement in a flow path portion of a turbomachine is provided, which, relative to a flow pattern in flow path portion, has a leading edge and, downstream thereof, a trailing edge, as well as a suction side and a pressure side; relative to a longitudinal axis of the turbomachine, viewed in the axial direction, in a radially inner portion, forming a first angle α with a circular arc about the longitudinal axis, and, in a radially outer portion, a second angle γ with a circular arc about the longitudinal axis. The guide vane airfoil is inclined in the outer portion, thus γ−90°, in terms of absolute value, being >0° (|γ−90°|>0°), and the guide vane airfoil being more highly inclined in the outer portion than in the inner portion, thus γ−90°, in terms of absolute value, being >α−90° (|γ−90°|>α−90°).

A blade wheel of a turbomachine, which blade wheel has a multiplicity of blades which are suitable and provided for extending radially in a flow path of the turbomachine, wherein the blades form a blade entry angle and a blade exit angle. Provision is made whereby the blade wheel forms N blocks of blades, where N≥2, wherein the blades of a block have in each case the same blade entry angle and the same blade exit angle, and the blades of at least two mutually adjacent blocks have a different blade entry angle and/or a different blade exit angle. According to a further aspect of the invention, partial gaps that the blades form in relation to an adjacent flow path boundary are varied in mutually adjacent blocks.

A steam turbine including a rotor shaft, a plurality of moving blade rows, a casing, and fixed blade rows disposed on a first side in the axial direction, relative to each of the plurality of moving blade rows. The last fixed blade row, disposed furthest on a second side in the axial direction among the plurality of moving blade rows, includes a plurality of fixed blades disposed at intervals in the circumferential direction and each extending in the radial direction; an outside ring having an annular shape and being disposed on the outside, in the radial direction, of the plurality of fixed blades; and an inside ring having an annular shape and being disposed on the inside, in the radial direction, of the plurality of fixed blades.

A gas turbine engine has a first spool having a low pressure compressor section disposed forward of an air inlet along a direction of travel of the engine, and a low pressure turbine section disposed forward of the low pressure compressor section and drivingly engaged thereto. A second spool has a high pressure compressor section disposed forward of the low pressure compressor section, and a high pressure turbine section disposed forward of the high pressure compressor section and drivingly engaged thereto. The high pressure turbine section is disposed aft of the low pressure turbine section. An output drive shaft drivingly engages the low pressure turbine section and extends forwardly therefrom to drive a rotatable load. A method of operating a gas turbine engine is also discussed.

A bearing compartment seal for a gas turbine engine includes a seal ring that defines an axis and has a radially inward facing sealing surface. A seal runner is configured to rotate relative to the seal ring. The seal runner has a runner surface facing the radially inward facing sealing surface. A plurality of grooves are spaced circumferentially along the runner surface. The plurality of grooves have a length in an axial direction that is at least 50% of an axial length of the runner surface.

Variable bleed valves with inner wall controlled-flow circuits are disclosed. An example apparatus disclosed herein includes a casing segment defining a first flow path, a variable bleed valve port defining a second flow path, and a channel formed in the casing segment, the channel including a first opening into the first flow path, and a second opening into the second flow path, the channel defining a third flow path between the first opening and the second opening.

A gas turbine engine has a first spool having a low pressure compressor section disposed forward of an air inlet along a direction of travel of the engine, and a low pressure turbine section disposed forward of the low pressure compressor section and drivingly engaged thereto. A second spool has a high pressure compressor section disposed forward of the low pressure compressor section, and a high pressure turbine section disposed forward of the high pressure compressor section and drivingly engaged thereto. The high pressure turbine section is disposed aft of the low pressure turbine section. An output drive shaft drivingly engages the low pressure turbine section and extends forwardly therefrom to drive a rotatable load. A method of operating a gas turbine engine is also discussed.