A gas turbine engine comprises a fan mounted to rotate about a main longitudinal axis; an engine core, comprising in axial flow series a compressor, a combustor, and a turbine coupled to the compressor through a shaft; a reduction gearbox that receives an input from the shaft and outputs drive to the fan so as to drive the fan at a lower rotational speed than the shaft; wherein the compressor comprises a first stage at an inlet and a second stage, downstream of the first stage, comprising respectively a first rotor with a row of first blades and a second rotor with a row of second blades, the first and second blades comprising respective leading edges, trailing edges and tips, and wherein the ratio of a maximum leading edge radius of the first blades to a maximum leading edge radius of the second blades is greater than 2.8.

A rotor is provided for a gas turbine engine. The rotor includes a rim that extends transverse to the web. The rim has a rotor spacer arm which defines a coating pocket and a stress relief protrusion opposite the coating pocket.

A turbine blade includes a blade body in which a suction side (51) facing one side in a circumferential direction and a pressure side (52) facing the other side in the circumferential direction are connected at a leading edge and a trailing edge; and a shroud provided at a tip which is a radially outer end portion of the blade body. The shroud includes a shroud body having an outer circumferential surface facing radially outward, a front end surface extending to both sides in the circumferential direction with a leading edge side of the blade body as a reference point (P1), a rear end surface extending to both sides in the circumferential direction with a trailing edge side of the blade body as a reference point (P2), and a contact surface provided on both sides in the circumferential direction, and a reinforcing portion which protrudes from the outer circumferential surface.

A system and methods are provided for pre-stressing blade elements for a gas turbine engine. In one embodiment, a method includes rotating a blade element relative to an axis. The method may also include controlling rotational speed of the blade element to generate residual stress in the blade element. The method may also include rotating multiple blade elements and fan blade units to generate residual stress. Blade elements may be rotated to exceed a maximum operating speed of the blade element to 120% of the maximum operating speed of the blade element.

A method of manufacturing an airfoil includes creating a plurality of cavities separated by a plurality of internal ribs in an airfoil forging. At least one hole is drilled in at least one of the plurality of internal ribs with a waterjet drilling tool. At least one hole extends perpendicularly to a wall of the rib.

A gas turbine engine comprises a fan mounted to rotate about a main longitudinal axis; an engine core, comprising in axial flow series a compressor, a combustor, and a turbine coupled to the compressor through a shaft; a reduction gearbox that receives an input from the shaft and outputs drive to the fan so as to drive the fan at a lower rotational speed than the shaft; wherein the compressor comprises a first stage at an inlet and a second stage, downstream of the first stage, comprising respectively a first rotor with a row of first blades and a second rotor with a row of second blades, the first and second blades comprising respective leading edges, trailing edges and tips, and wherein the ratio of a maximum leading edge radius of the first blades to a maximum leading edge radius of the second blades is greater than 2.8.

An integrated bladed rotor of a gas turbine engine is provided. The integrated bladed rotor includes a hub having a rotation axis and a radially outer platform relative to the rotation axis, and a plurality of blades extending radially outwardly from the outer platform of the hub. The blades are integrally formed with the hub to define a monolithic component with the hub. Two or more of the blades each include: an airfoil including a groove formed in an outer surface of the airfoil to mitigate crack propagation, and a root fillet providing a transition between the outer platform of the hub and the airfoil.

An impeller for a centrifugal compressor, the impeller rotatable about a central axis, has: an outer hub body including a first material and extending around the central axis, the outer hub body defining a gaspath face extending from an inlet to an outlet, the gaspath face extending radially away from the central axis from the inlet to the outlet; blades protruding from the gaspath face and circumferentially distributed around the central axis; and an inner hub body extending around the central axis, the inner hub body secured to the outer hub body, the outer hub body axially overlapping and extending around the inner hub body, the inner hub body made of a second material being more cold dwell resistant than the first material.

A method of monitoring a component includes providing the component which includes a body having an exterior surface and a plurality of passive strain indicators configured on the exterior surface. The method includes directly measuring the component with at least one three-dimensional data acquisition device. The direct measurement generates a first point cloud and a plurality of second point clouds. The first point cloud corresponds to the exterior surface and includes a plurality of first data points, each data point having an X-axis coordinate, a Y-axis coordinate, and a Z-axis coordinate. Each second point cloud corresponds to one of the plurality of passive strain indicators and includes a plurality of second data points, each data point having an X-axis coordinate, a Y-axis coordinate, and a Z-axis coordinate. A second data point density of each second point cloud is greater than a first data point density of each first point cloud.

High cycle fatigue (HCF) in a turbine wheel of a sector-divided dual volute turbocharger, particularly a turbocharger where the tongue-to-blade gap is as small as from 1-3% of the wheel diameter, is reduced using a turbine wheel with (blade stiffness/backwall stiffness100) between 41 and 44.