A component is provided and includes a substrate comprising an outer and an inner surface, where the inner surface defines at least one hollow, interior space. The component defines one or more grooves, where each groove extends at least partially along the outer surface of the substrate and has a base and a top. The base is wider than the top, such that each groove comprises a re-entrant shaped groove. One or more access holes are formed through the base of a respective groove, to connect the groove in fluid communication with the respective hollow interior space. Each access hole has an exit diameter D that exceeds the opening width d of the top of the respective groove. The diameter D is an effective diameter based on the area enclosed. The component further includes at least one coating disposed over at least a portion of the surface of the substrate, wherein the groove(s) and the coating together define one or more re-entrant shaped channels for cooling the component. A method for manufacturing the component is also provided. A method for manufacturing a component is also provided, where the groove and the access hole(s) are machined as a single continuous process, such that the groove and the access hole(s) form a continuous cooling passage.

A cooling mechanism includes a bottom wall (22) in contact with a combustion chamber, an upper wall (30), and a cooling passage (40) arranged between the bottom wall (22) and the upper wall (30). The cooling passage (40) includes a first passage (50) extending to a first direction, a second passage (60) extending to the first direction, and a connection section (70) connected with the first passage (50) and the second passage (60). The second passage (60) is arranged to have an offset to the first passage (50) in a second direction perpendicular to the first direction and along the bottom wall (22).

A turbine airfoil apparatus includes: an airfoil including a concave pressure sidewall and a convex suction sidewall joined together at a leading edge and at a trailing edge; an endwall that projects laterally outwardly from the airfoil at one spanwise end thereof, the endwall having an outer surface facing the airfoil and an opposing inner surface; a plenum defined within the endwall between the inner and outer surfaces wherein the plenum is forked in plan view, with at least two branches, each branch terminating at a closed end, each branch having a throat disposed at its upstream end, wherein each throat has a relatively constricted flow area for increasing flow velocity; and at least one film cooling hole passing through the outer surface and communicating with the plenum.

Methods for forming a hole in a coated component are provided. The method may include forming a sacrificial layer over a ceramic barrier coating of a substrate, drilling a hole into the coated component such that any spatter formed during drilling deposits onto the sacrificial layer, and removing the sacrificial layer along with the spatter deposited thereon. The sacrificial layer may include a rare earth oxide (e.g., rare earth oxide particles). Intermediate ceramic matrix composite (CMC) component are also provided. The intermediate CMC may include a CMC body, an environmental barrier coating on the bond coating, and a sacrificial layer on the environmental barrier coating, with the sacrificial layer including particles of a rare earth oxide dispersed in a polymeric matrix.

An airfoil having a wall structure including a plurality of spaced walls for improved cooling and lifetime is disclosed. The airfoil and walls are made by additive manufacturing. The airfoil includes an exterior wall, an intermediate wall, and an interior wall each separated from adjacent walls by a plurality of standoff members; a plurality of outer cooling chambers defined between the exterior and intermediate walls, the chambers partitioned by an outer partition; a plurality of intermediate cooling chambers defined between the intermediate and interior walls, the chambers partitioned by an intermediate partition; a thermal barrier coating on each of the exterior wall and the intermediate wall; a first plurality of impingement openings through the intermediate wall; a second plurality of impingement openings through the interior wall; and a plurality of cooling passages through the exterior wall.

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 turbine blade having a labyrinth of internal channels for circulation of coolant received through an inlet formed in a terminal portion of a blade root. A labyrinth geometry includes: (i) the inlet arranged on an axially upstream face of the terminal portion leading to an upstream duct portion having a first section adjacent the inlet and a second section having a reduced cross-section compared to the first section, (ii) a leading edge passage intersecting with the first section and extending through a blade body towards a tip of the blade, where a proximal end of the leading edge passage is angled towards a direction of incoming air flow, (iii) a main blade passage intersecting with a downstream duct portion arranged in axial alignment with, and separate from, the upstream duct portion, and (iv) a restrictor passage intersecting with a mid-blade passage and extending towards a mid-blade duct portion.

An airfoil for a gas turbine engine is disclosed. The airfoil may include a first portion including a first slot, a second portion including a second slot, and a biscuit disposed within the first slot and the second slot. The first portion and the second portion may be joined by the biscuit. A method for constructing an airfoil is also disclosed. The method may include making a first slot on a sheath, the first slot sized to fit a first part of a biscuit; making a second slot on a body, the second slot sized to fit a second part of the biscuit; and joining the sheath and the body together through a biscuit joint, the biscuit disposed within the first slot and the second slot.

A turbine component includes an airfoil-shaped core having an outer peripheral surface. A plurality of channels is formed in the core, each opening to the outer peripheral surface. The channels extend substantially radially to be elongated in the radial direction. A first platform is attached to the core. The component also includes an airfoil-shaped non-permeable skin having a hollow interior, an inner peripheral surface and an outer peripheral surface. The skin is sized so that the core can be received in the hollow interior of the skin. A second platform is attached to the skin. The core is received in the hollow interior of the skin such that the outer peripheral surface of the core engages the inner peripheral surface of the skin such that a plurality of generally radial cooling channels are formed between the channels in the core and the inner peripheral surface of the skin.

Methods for forming a hole in a coated component are provided. The method may include forming a sacrificial layer over a ceramic barrier coating of a substrate, drilling a hole into the coated component such that any spatter formed during drilling deposits onto the sacrificial layer, and removing the sacrificial layer along with the spatter deposited thereon. The sacrificial layer may include a rare earth oxide (e.g., rare earth oxide particles). Intermediate ceramic matrix composite (CMC) component are also provided. The intermediate CMC may include a CMC body, an environmental barrier coating on the bond coating, and a sacrificial layer on the environmental barrier coating, with the sacrificial layer including particles of a rare earth oxide dispersed in a polymeric matrix.