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: 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: 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: 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: A gas turbine engine wash process that facilitates reducing a formation of particulate matter within a gas turbine engine is described. The engine wash process includes injecting a first liquid into the engine to remove particulate matter formed within the engine and adversely affecting engine operation and performance. A second liquid is then injected into the engine to facilitate reducing a rate of formation of particulate matter within the gas turbine engine as the engine is operated in the future. More specifically, the second liquid is an anti-static liquid that coats compressor blades within the gas turbine engine.

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: 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 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: The back side recessed cooling surface of a shroud defining in part the hot gas path of a turbine is electrochemically machined to provide surface roughness elements and spaces therebetween to increase the heat transfer coefficient. To accomplish this, an electrode with insulating dielectric portions and non-insulating portions is disposed in opposition to the cooling surface. By passing an electrolyte between the cooling surface and electrode and applying an electrical current between the electrode and a shroud, roughness elements and spaces therebetween are formed in the cooling surface in opposition to the insulating and non-insulating portions of the electrode, hence increasing the surface area and heat transfer coefficient of the shroud.

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: An engine, according to an exemplary embodiment of the invention, comprises a compressor which compresses inlet air; a combustor in which a mixture of fuel and air is combusted; a turbine which is driven by gases from the combustor; and a dielectric coating applied to a surface of at least one of: the compressor and the turbine, the dielectric coating having a dielectric constant of at least 3.0 and a loss tangent of at most 0.1, wherein the dielectric coating reduces the magnitude of an electrostatic force which attracts particles flowing through the engine to the surface of the engine. In operation, only a thin layer of particles typically accumulates on the dielectric coating. While the dielectric coating reduces the magnitude of the electric field which attracts particles, the repulsive force produced by the accumulated particles repels additional particles of the same charge.