The present disclosure provides methods, assemblies, and systems for power production that can allow for increased efficiency and lower cost components arising from the control, reduction, or elimination of turbine blade mechanical erosion by particulates or chemical erosion by gases in a combustion product flow. The methods, assemblies, and systems can include the use of turbine blades that operate with a blade velocity that is significantly reduced in relation to conventional turbines used in typical power production systems. The methods and systems also can make use of a recycled circulating fluid for transpiration protection of the turbine and/or other components. Further, recycled circulating fluid may be employed to provide cleaning materials to the turbine.

A method for providing CAM manufacturing instructions for the powder-bed-based additive manufacturing of a component wherein a geometry of the component, with a solid material region, a transition region, and a porous component region, is defined on the basis of CAD data. Irradiation parameters for the manufacturing of the component, including an irradiation power, a scanning speed, a scanning pitch, and a layer thickness, are varied within the transition region in such a way as to form a porosity gradient of the structure of the component between the solid material region of the component and the porous component region.

An apparatus and method for flowing cooling air through an outer wall of an engine component such as an airfoil. The airfoil having the outer wall can include an opening. A framework can be disposed in the opening adapted to reduce the required flow through the opening to increase the efficiency of the engine and improve cooling.

An airfoil for a gas turbine engine is provided that includes a first portion formed from a first plurality of plies of a ceramic matrix composite material and defining an inner surface of the airfoil, as well as a second portion formed from a second plurality of plies of a ceramic matrix composite material and defining an outer surface of the airfoil. The first portion and the second portion define a non-line of sight cooling aperture extending from the inner surface to the outer surface of the airfoil. In one embodiment, a surface angle that is less than 45 is defined between a second aperture and the outer surface. A method for forming an airfoil for a gas turbine engine also is provided.

An apparatus for a gas turbine engine can include an airfoil having an interior. The interior can be separated into one or more cooling air channels extending in a span-wise direction. An accelerator insert can be placed in one or more cooling air channels to define a reduced cross-sectional area within the cooling air channel to accelerate an airflow passing through the cooling air channel.

A gas turbine engine has a converging duct that has combustion products flow at low mach speeds through a first portion and a high mach speeds through a second portion. The converging duct has two types of cooling schemes formed. One type of cooling scheme is beneficial for the low mach speed combustion product flow and one type of cooling scheme is beneficial for the high mach speed combustion product flow. The two cooling schemes are blended together in order increase the efficiency of the cooling of the converging duct.

A tip cooling apparatus for a turbine airfoil includes: a tip cap; a pair of spaced-apart tip walls connected to, extending around, and projecting outwardly from the tip cap so as to surround a central portion of the tip cap; a pocket defined by the tip walls; at least one feed hole passing through the tip cap or tip walls, communicating with the pocket; and a cooling matrix disposed in the pocket, the cooling matrix being an organized structure including an inlet surface having a plurality of inlets communicating with the pocket, and an outlet surface having a plurality of outlets, and further comprising a plurality of interior passages interconnecting the inlets to the outlets, with no line-of-sight therebetween.

A rocket engine section includes a combustion chamber body having an inner wall and a channel carrying a cooling medium extending outside and along the inner wall. The rocket engine section further comprises a porous portion integrally formed with the inner wall and integral with the inner wall and adapted to allow the cooling medium carried in the channel to pass from the channel to the interior of the combustion chamber body. A porosity of the porous portion determines a volume flow rate and/or mass flow rate of the cooling medium let through into the interior of the combustion chamber body.

A heat shield for a gas turbine engine having a combustor includes an annular configuration extending substantially 360 degrees about the combustor for protecting a dome portion thereof, which is formed by radially extending flanges of inner and outer liners of the combustor. The heat shield fixedly secures the radially extending flanges of the inner and outer liners together in a sealing relationship such as to structurally form the dome portion of the combustor. The heat shield is disposed internally within the combustor and substantially entirely overlying the dome portion. The heat shield includes at least two separate heat shield segments cooperating to provide the annular heat shield, each heat shield segment being sheet metal and including at least two circumferentially spaced apart openings therein for receiving fuel nozzles therethrough. Each of the heat shield segments has a circumferential span not exceeding 180 degrees.

An engine comprises an airfoil having at least one internal cooling circuit extending radially from the longitudinal axis of the engine. The cooling circuit is defined by at least one rib extending across an interior of the airfoil and at least one internal wall defining an internal passage. The internal wall further defines one or more near wall cooling passages. A thermal stress reduction structure is provided between the rib and the internal wall, providing efficient cooling at a junction between the rib and the internal wall.