Abstract: An improved sealing device for use between a transition duct aft frame and turbine inlet is disclosed. The improved sealing device includes a plurality of corrugated metal seals that are secured to the transition duct aft frame along the arc-like sections of the aft frame. The corrugated seals contact both the transition duct aft frame and turbine inlet to provide a more effective seal and to control the amount of compressor discharge air introduced to cool the turbine vane platforms. In the preferred embodiment, the corrugated seals are coated to reduce wear, fretting, and galling and are used in conjunction with a transition duct thermally free aft frame and pivot bearing mounting system. An alternate embodiment of the seal is also disclosed that utilizes an alternate cooling hole pattern for providing additional cooling air to the turbine vane platform. A further alternate embodiment of the seal incorporates a group of wear reduction coatings from which to select.

Abstract: A method for providing cooling air to the venturi and the combustion chamber in a low NOx emission combustor as used in a gas turbine engine that includes the steps of providing an annular air passage surrounding said combustion chamber and venturi where said cooling air under pressure enters the combustion chamber/venturi near the aft portion of the combustion chamber, passing the air along the combustion chamber, past the venturi where the air exits near the front portion of the convergent area of the venturi. The method prevents any channel/passage cooling air from being received into the combustion chamber, and at the same time, introduces the outlet of the cooling air, after the air has passed over the combustion chamber of the venturi and has been heated, back into the premix chamber thereby improving the efficiency of the combustor while reducing and lowering NOx emission in the combustion process.

Abstract: A turbine blade including an airfoil having a profile in accordance with Table 1 is disclosed. The turbine blade has a plurality of cooling passages extending radially outward through the airfoil. The aerodynamic profile of the airfoil has been reconfigured to further reduce overall heat load to the airfoil while paying particular attention to the leading edge region. Specifically, the airfoil leading edge, which is the life-limiting location of the turbine blade has been reconfigured to lower heat load and allow for increased cooling, thereby increasing turbine blade life.

Abstract: A gas turbine blade having an airfoil to platform interface configured to minimize thermal and vibratory stresses is disclosed. This configuration minimizes exposure to the conditions that are known to cause high cycle fatigue and low cycle fatigue cracks. The turbine blade incorporates a channel in the platform trailing edge that extends from the platform concave face to the platform convex face and has a portion having a constant radius. The channel extends a sufficient distance into a stress field created by the aerodynamic loading of the turbine blade airfoil in order to redirect the mechanical stresses away from the blade trailing edge while allowing the platform trailing edge region to be more responsive to thermal fluctuations.

Abstract: A removable instrumentation assembly and probe for use in simultaneously measuring dynamic pressure, at least one static pressure, and temperature for a gas turbine combustor. The instrumentation assembly allows combustor performance analysis as well as monitoring of component integrity through dynamic pressure fluctuations. The instrumentation assembly includes a probe having a plurality of passages, each connected to tubular conduits for measuring and recording respective pressures. In the preferred embodiment, dynamic pressures from within a combustion chamber are measured and recorded along with static pressures within the combustion chamber and outside of the combustion chamber, along with external air temperature.

Abstract: A dual fuel premix nozzle and method of operation for use in a gas turbine combustor is disclosed. The dual fuel premix nozzle utilizes a fin assembly comprising a plurality of radially extending fins for injection of gas fuel and compressed air in order to provide a more uniform injection pattern and homogeneous mixture. The premix fuel nozzle includes a plurality of coaxial passages, which provide gaseous fuel and compressed air to the fin assembly. When in liquid fuel operation, the gas circuits are purged with compressed air and liquid fuel and water pass through coaxial passages to the tip of the dual fuel premix fuel nozzle, where they inject liquid fuel and water into the secondary combustion chamber. An alternate embodiment includes an additional gas fuel injection region located along a conically tapered portion of the premixed fuel nozzle, downstream of the fin assembly.

Abstract: A crossfire tube assembly with telescoping inner and outer crossfire tubes with an enhanced cooling mechanism for connecting adjacent combustors in a gas turbine is disclosed. The enhanced cooling configuration includes a plurality of channels formed in the telescoping region of the inner and outer crossfire tubes of the assembly to improve heat transfer and reduce local operating temperatures such that component life is extended.

Abstract: A premix fuel nozzle and method of operation for use in a gas turbine combustor is disclosed. The premix fuel nozzle utilizes a fin assembly comprising a plurality of radially extending fins for injection of fuel and compressed air in order to provide a more uniform injection pattern. The fuel and compressed air mixes upstream of the combustion chamber and flows into the combustion chamber as a homogeneous mixture. The premix fuel nozzle includes a plurality of coaxial passages, which provide fuel and compressed air to the fin assembly, as well as compressed air to cool the nozzle cap assembly. An alternate embodiment includes an additional fuel injection region located along a conically tapered portion of the premixed fuel nozzle, downstream of the fin assembly.

Abstract: A premix fuel nozzle and method of operation for use in a gas turbine combustor is disclosed. The premix fuel nozzle utilizes a fin assembly comprising a plurality of radially extending fins for injection of fuel and compressed air in order to provide a more uniform injection pattern. The fuel and compressed air mixes upstream of the combustion chamber and flows into the combustion chamber as a homogeneous mixture. The premix fuel nozzle includes a plurality of coaxial passages, which provide fuel and compressed air to the fin assembly, as well as compressed air to cool the nozzle cap assembly.

Abstract: An improved sealing device for use between a transition duct aft frame and turbine inlet is disclosed. The improved sealing device includes a plurality of corrugated metal seals that are secured to the transition duct aft frame along the arc-like sections of the aft frame. The corrugated seals contact both the transition duct aft frame and turbine inlet to provide a more effective seal and to control the amount of compressor discharge air introduced to cool the turbine vane platforms. In the preferred embodiment, the corrugated seals are coated to reduce wear, fretting, and galling and are used in conjunction with a transition duct thermally free aft frame and pivot bearing mounting system. An alternate embodiment of the seal is also disclosed that utilizes an alternate cooling hole pattern for providing additional cooling air to the turbine vane platform.

Abstract: A transition duct having a panel assembly with an inlet end of generally circular cross section and an outlet end having a generally rectangular arc-like cross section is disclosed. The panel assembly has an uncoated internal profile substantially in accordance with coordinate values X, Y, and Z as set forth in Table 1 carried only to three decimal places wherein the coordinates are taken at a sweep angle &thgr; wherein &thgr; is an angle measured from said inlet end and X, Y, and Z are coordinates defining the panel assembly profile at each angle &thgr; from the inlet end. An alternate embodiment is also disclosed defining an envelope for the uncoated internal profile of the panel assembly.

Abstract: An effusion cooled transition duct for transferring hot gases from a combustor to a turbine is disclosed. The transition duct includes a panel assembly with a generally cylindrical inlet end and a generally rectangular exit end with an increased first and second radius of curvature, a generally cylindrical inlet flange, and a generally rectangular end frame. Cooling of the transition duct is accomplished by a plurality of holes angled towards the end frame of the transition duct and drilled at an acute angle relative to the outer wall of the transition duct. The combination of the increase in radii of curvature of the panel assembly with the effusion cooling holes reduces component stresses and increases component life. An alternate embodiment of the present invention is shown which discloses shaped angled holes for improving the film cooling effectiveness of effusion holes on a transition duct while reducing film blow off.

Abstract: A transition duct with a thermally free aft frame for use in a gas turbine engine is disclosed. The transition duct includes an aft frame that is thermally free through the use of a plurality of retention lugs, bushings, and bulkhead assemblies. The aft frame is allowed to adjust from thermal changes as a result of relative sizing between the bushings and retention lugs of the aft frame. An additional feature of this invention is the use of radially extending ribs along the sidewalls of the aft frame, to form an interlocking sealing means with adjacent transition ducts to reduce the amount compressor air leakage into the turbine inlet.

Abstract: Interaction between mating gas turbine combustor components due to vibrations and assembly tolerances can cause excessive wear and premature replacement. Typically, wear reduction features, such as hardened materials, are used to minimize the amount of wear or direct such wear to a specific component. The present invention discloses an improved wear reduction device for the interface between a gas turbine combustor transition duct end frame and the turbine inlet. The improved wear reduction device incorporates “L-shaped” wear strip inserts, constructed of a hardened material, and fixed along the sidewalls of the end frame to protect it from wear by the mating turbine inlet seal. The improved wear strip insert provides a cost savings by not requiring costly manufacturing tooling to form the wear strip inserts, unlike previous wear reduction techniques for the same component interface.

Abstract: An effusion cooled transition duct for transferring hot gases from a combustor to a turbine is disclosed. The transition duct includes a panel assembly with a generally cylindrical inlet end and a generally rectangular exit end with an increased first and second radius of curvature, a generally cylindrical inlet sleeve, and a generally rectangular end frame. Cooling of the transition duct is accomplished by a plurality of holes angled towards the end frame of the transition duct and drilled at an acute angle relative to the outer wall of the transition duct. Effusion cooling geometry, including coverage area, hole size, and surface angle will be optimized in the transition duct to tailor the temperature levels and gradients in order to minimize thermally induced stresses. The combination of the increase in radii of curvature of the panel assembly with the effusion cooling holes reduces component stresses and increases component life.

Abstract: An improved gas turbine blade is disclosed that utilizes a blade tip shroud with tapered shroud pockets to remove excess weight from the shroud while not compromising shroud bending stresses. Excess shroud weight removed by the tapered pockets reduces overall blade pull while maintaining material necessary to increase shroud stiffness. The resulting rib created between the tapered pockets provides a surface, away from possible areas of stress concentration, for drilling radial cooling holes.

Abstract: A wear reduction means for a fuel nozzle interface of an industrial gas turbine combustor is disclosed. The wear reduction means includes a replaceable insert welded into the engagement location of the fuel nozzle tip. The fuel nozzle tip is coated with a material harder than the replaceable insert, such that any wear due to mechanical contact of the mating components is directed to the replaceable insert.

Abstract: A combustion liner assembly for reducing nitric oxide (NOx) emissions is disclosed. This combustion liner utilizes an annular plenum outside the liner shell for the purpose of containing cooling air that has been heated and reintroducing it into the combustion process. The air plenum can be enlarged to increase the amount of cooling air contained within and still allow for installation of the liner assembly into the combustor by utilizing recesses that locally reduce the diameter of the air plenum to allow it to pass by liner mounting pegs within the combustor assembly.