Abstract: An article includes turbulation material bonded to a surface of a substrate via a bonding agent, such as a braze alloy. In an embodiment, the turbulation material includes a particulate phase of discrete metal alloy particles having an average particle size within a range of about 125 microns to about 4000 microns. Other embodiments include methods for applying turbulation and articles for forming turbulation.

Abstract: Castings for gas turbine parts exposed on one side to a high-temperature fluid medium have cast-in bumps on an opposite cooling surface side to enhance heat transfer. Areas on the cooling surface having defectively cast bumps, i.e., missing or partially formed bumps during casting, are thermally sprayed to provide a metallic cooling enhancement surface layer to salvage the part.

Abstract: A combustor liner is provided on its backside cooling surface with a braze alloy coating and cooling enhancement material, preferably metallic particles to enhance the heat transfer between the liner and the cooling medium. The surface area of the backside coated area is increased substantially by the coating and particles in relation to the uncoated surface areas. Consequently, the life of the liner is extended.

Abstract: Castings for gas turbine parts exposed on one side to a high-temperature fluid medium have cast-in bumps on an opposite cooling surface side to enhance heat transfer. Areas on the cooling surface having defectively cast bumps, i.e., missing or partially formed bumps during casting, are coated with a braze alloy and cooling enhancement material to salvage the part.

Abstract: Castings for gas turbine parts exposed on one side to a high-temperature fluid medium have cast-in bumps on an opposite cooling surface side to enhance heat transfer. Areas on the cooling surface having defectively cast bumps, i.e., missing or partially formed bumps during casting, are coated with a braze alloy and cooling enhancement material to salvage the part.

Abstract: A turbine bucket includes an airfoil extending from a platform, having high and low pressure sides; a wheel mounting portion; a hollow shank portion located radially between the platform and the wheel mounting portion, the platform having an under surface. An impingement cooling plate is located in the hollow shank portion, spaced from the under surface, and the impingement plate is formed with a plurality of impingement cooling holes therein.

Abstract: An annular turbine shroud separates a hot gas path from a cooling plenum containing a cooling medium. Bumps are cast in the surface on the cooling side of the shroud. A surface coating overlies the cooling side surface of the shroud, including the bumps, and contains cooling enhancement material. The surface area ratio of the cooling side of the shroud with the bumps and coating is in excess of a surface area ratio of the cooling side surface with bumps without the coating to afford increased heat transfer across the element relative to the heat transfer across the element without the coating.

Abstract: A surface of an article, for example an external fluid flow surface, includes a plurality of metal wires lengthwise of the wires along the article surface. The article can be in the form of a component of an apparatus, for example a component of a gas turbine engine, the wires being bonded along and modifying surface characteristics of the article. Also, the article can be in the form of a bonding layer, for example a brazing tape, including the metal wires carried along a surface of the layer.

Abstract: A casting includes a heat transfer surface having a plurality of cavities. The plurality of cavities include a density of at least about 25 cavities per square centimeter to about 1,100 cavities per square centimeter resulting in increased surface area and therefore enhanced heat transfer capability. Also disclosed is a mold for forming a pattern for molding the casting. The mold includes a surface defining a portion of a chamber to which are attached a plurality of particles having an average particle size in a range of about 300 microns to about 2,000 microns.

Abstract: A casting includes a heat transfer surface having a plurality of cavities. The plurality of cavities include a density of at least about 25 cavities per square centimeter to about 1,100 cavities per square centimeter resulting in increased surface area and therefore enhanced heat transfer capability. A mold for forming a pattern for molding the casting includes a surface defining a portion of a chamber to which are attached a plurality of particles having an average particle size in a range of about 300 microns to about 2,000 microns.

Abstract: A casting includes a heat transfer surface having a plurality of cavities. The plurality of cavities include a density of at least about 25 cavities per square centimeter to about 1,100 cavities per square centimeter resulting in increased surface area and therefore enhanced heat transfer capability. Also disclosed is a mold for forming a pattern for molding the casting. The mold includes a surface defining a portion of a chamber to which are attached a plurality of particles having an average particle size in a range of about 300 microns to about 2,000 microns.

Abstract: A method for modifying cooling holes in a gas turbine engine film-cooled component by machining cooling hole outlets to enlarge the outlets and remove any portion of the cooling hole walls which might exhibit cracks.

Abstract: A method is described for improving the cooling effectiveness of a fluid which flows through a row of passage holes in a substrate (e.g., a turbine component), out to a high-temperature surface of the substrate. The method involves forming a slot over the holes, within the high temperature surface of the substrate. The slot can be formed within protective coatings applied over the substrate. Alternatively, it can be formed partially within the substrate, and partially within the protective coatings. Movement of a film coolant through the substrate and into the slot results in greater cooling effectiveness. Related articles are also described.

Abstract: An airfoil with a reduced heat load for use in either a turbine or a compressor of a gas turbine engine comprises having at least one heat reducing dimple on the body of the airfoil or on the associated endwall of the airfoil. The body of the airfoil is comprised of a leading edge, a trailing edge, a pressure side and a suction side. The length of the heat reducing dimple in the expected direction of hot gas stream flow is at least equal to or greater than the width transverse to such direction. The heat reducing dimple is located on the airfoil or endwall so as to reduce the heat load as the hot gas stream flow passes from the leading edge to the trailing edge.

Abstract: A first-stage turbine blade includes an airfoil having a profile according to Table I. The airfoil has a plurality of cooling air passages extending linearly from the root portion to the tip portion of the airfoil. The blade includes a shank having a pair of cavities in communication through the blade dovetail with a plenum in the wheel space for supplying cooling air to the passages in the airfoil. The cooling passages in the airfoil terminate in a recess at the tip portion which has an opening adjacent the trailing edge of the airfoil and along the suction side to enable egress of cooling air into the hot gas stream on the low pressure side of the airfoil. The majority of the cooling passages are turbulated. Certain of those passages are arranged in rows lying adjacent to the pressure and suction sides of the airfoil.

Abstract: A combustor liner includes an inner layer for facing combustion gases, and an opposite outer layer for facing a cooling fluid. The outer layer has a greater coefficient of thermal conductivity than the inner layer for reducing temperature gradients in the liner. In a preferred embodiment, the outer layer significantly reduces temperature gradients in the liner which are caused by the varying cooling ability of impingement cooling air jets for more uniformly cooling the combustor liner and reducing the maximum temperature thereof.

Abstract: Methods of making gas turbine structures with cooling channels, such as, for example, combustor/transition pieces for gas turbines having a double wall with a plurality of cooling channels, having axially and/or circumferential cross-flow passages positioned between the structure's inner member and the outer member to provide cooling air thereto, are disclosed.

Abstract: Methods of making cylindrical structures with cooling channels, such as, for example, combustor/transition pieces for gas turbines having a double wall with a plurality of cooling channels, both axially and, in some cases, circumferential cross-flow passages positioned between the structure's inner member and the outer member to provide cooling air thereto, are disclosed. The cooling channels are formed in the area between the inner member of the structure and the outer member thereof. The passages preferably extend both axially and circumferentially with respect to the direction of flow through the structure. The axial passages extend completely from one end to the other and the circumferential passages extend around the circumference of the structure.

Abstract: A combustor liner includes an inner layer for facing combustion gases, and an opposite outer layer for facing a cooling fluid. The outer layer has a greater coefficient of thermal conductivity than the inner layer for reducing temperature gradients in the liner. In a preferred embodiment, the outer layer significantly reduces temperature gradients in the liner which are caused by the varying cooling ability of impingement cooling air jets for more uniformly cooling the combustor liner and reducing the maximum temperature thereof.

Abstract: A combustor/transition piece for a gas turbine including a double walled structure having a plurality of cooling channels, both axially and, in some cases, circumferential cross-flow passages positioned between the structure's inner member and the outer member to provide cooling air thereto, are formed in the area between the inner member of the combustor and the outer member thereof. The passages preferably extend both axially and circumferentially with respect to the direction of flow through the combustor/transition piece. The axial passages extend completely from one end to the other and the circumferential passages extend around the circumference of the combustor/transition piece. The addition of a circumferential cross-flow passage connecting axial flow coolant passages in double wall turbine components can prevent combustor/transition piece part failure due to axial passage inlet blockage without affecting normal, unblocked cooling.