Abstract: Voltage in a transfer arc power supply of a plasma jet cleaning apparatus employed to induce a cathode workpiece current for cleaning a surface of the workpiece includes apparatus for cyclically varying the applied voltage between at least two negative levels which are effective to induce two levels of workpiece current. The more negative voltage is effective to produce a large workpiece current and to clean dielectric impurities from the surface of the workpiece. The less negative voltage is effective to maintain current flow but to permit enhanced motion of the plasma jet over the workpiece surface so that any tendency for sticking of cathode spots on the workpiece during existence of the more negative voltage is counteracted.

Abstract: A catalytic combustor comprises a pilot zone having means to introduce fuel therein; upstream of said pilot zone and communicating therewith a catalytically supported thermal combustion zone comprising a plurality of catalytically supported thermal combustion sections each comprising a solid oxidation catalyst, means for introducing air into said section and means to introduce fuel into said section; and means to control the rate of fuel flow in each of the means to introduce fuel into a catalytically supported thermal combustion section and the means to introduce fuel into the pilot zone. The combustor is operated by staging the fuel supply in order to maximize the amount of combustion in the catalytically supported thermal combustion zone and minimize NOx emissions under all load conditions.

Abstract: A flow divider is described for distributing a fluid, such as fluid oil, in equal volumes from a source to each of a plurality of fuel nozzles of a gas turbine machine. The flow divider includes a plurality of intermeshing gear sets, two rotatable shafts for connecting the gear sets together for operating in unison, a plurality of particulars axially positioned between adjacent gear sets, first and second partition retainers for immmovably positioning the partitions in the axial direction on the rotatable shafts and a split housing for enclosing the gear sets and shafts. Each of the rotatable shafts is mounted on bearings at each end of the housing with one end of each shaft being fixed and the other end being permitted to slide axially.

Abstract: An improved cooling system utilizes flow resistant devices distributing liquid coolant to air foil coolant channels in a bucket of a turbine. A separate flow resistance device associated with each of the air foil coolant channels resist the flow of liquid coolant into the coolant channels whereby a fluid head is developed in a standpipe upstream of the flow resistance devices. The fluid head, together with the outward radial acceleration meters the flow of fluid through each flow resistance device according to the head. In the disclosed embodiments, the flow resistant devices alternately take the form of a tortuous passage, an orifice and a plurality of vortex flow chambers.

Abstract: A closed-cycle gas turbine chemical processor separates the functions of combustion air and dilution fluid in a gas turbine combustor. The output of the turbine stage of the gas turbine is cooled and recirculated to its compressor from where a proportion is fed to a dilution portion of its combustor and the remainder is fed to a chemical recovery system wherein at least carbon dioxide is recovered therefrom. Fuel and combustion air are fed to a combustion portion of the gas turbine combustor. In a preferred embodiment of the invention, the gas turbine is employed to drive an electric generator. A heat recovery steam generator and a steam turbine may be provided to recover additional energy from the gas turbine exhaust. The steam turbine may be employed to also drive the electric generator. Additional heat may be added to the heat recovery steam generator for enhancing the electricity generated using heat recovery combustors in which the functions of combustion and dilution are separated.

Abstract: A flow control body in the aft end of a hollow core of a turbine vane provides localized increased velocity cooling air flow in a wide portion which is otherwise difficult to cool. The flow control body includes lands and grooves with the cooling air being constrained to flow through the grooves and provide localized cooling while conductive heat transfer through the lands to the flow control body provides substantial temperature uniformity along the length of the vane. Turbulence chambers may be formed in the flow control body to further control cooling and the shape or other parameters of the flow control body may be modified to accommodate uneven end-to-end heating of the vane.

Abstract: A state-of-the-art power plant in which the heat from solid or low quality fuels is utilized to heat indirectly a motive stream composition of a mixture of steam and gases to drive a gas turbine. The thermal energy from the burning of the solid or low quality fuels is also utilized to generate steam which powers a steam turbine. Excess steam may be generated to be utilized as process steam.

Abstract: A high-temperature combustor for burning low-BTU coal gas in a gas turbine is described. The combustor comprises a plurality of individual combustor chambers. Each combustor chamber has a main burning zone and a pilot burning zone. A pipe for the low-BTU coal gas is connected to the upstream end of the pilot burning zone: this pipe surrounds a liquid fuel source and is in turn surrounded by an air supply pipe: swirling means are provided between the liquid fuel source and the coal gas pipe and between the gas pipe and the air pipe. Additional preheated air is provided by counter-current coolant air in passages formed by a double wall arrangement of the walls of the main burning zone communicating with passages of a double wall arrangement of the pilot burning zone: this preheated air is turned at the upstream end of the pilot burning zone through swirlers to mix with the original gas and air input (and the liquid fuel input when used) to provide more efficient combustion.

Abstract: A transition portion adjacent the uncored section at a trailing edge of a cored turbine bucket displaces some of the regions of maximum stress concentration so that the maxima do not superpose and produce radial cracking at the junction of the uncored section with the walls of the cored portion. The transition section includes a curved portion joining a ramp leading to the tip.

Abstract: A sensor probe is affixed at an end of a probe adapter which includes an extended portion which is radially flexible but torsionally stiff. A guideway which passes from an accessible location in a machine to the vicinity or the target surface guides the sensor probe to its operative location. Final positioning of the sensor probe is attained by abutment of a forward shoulder on the probe adapter with an abutment shoulder fixed to the machine a predetermined distance from the target surface to be monitored. This permits removal and replacement of sensor probes without requiring final adjustment of the replacement sensor probe. One embodiment of the invention permits final adjustment and locking of the sensor probe in position after full assembly of the bearing housing by providing a star wheel on an adjustment sleeve which, after adjustment is locked in position by a setscrew.

Abstract: The present invention relates to a gas turbine power plant wherein the gas turbine is driven by gases and steam heated indirectly through a heat exchanger by the burning of corrosive fuels. One of the main improvements in the present invention is to utilize a state-of-the-art gas turbine in the power plant.

Abstract: A gas turbine nozzle guide vane assembly is formed of individual arcuate nozzle segments. The arcuate nozzle segments are elastically joined to each other to form a complete ring, with edges abutted to prevent leakage. The resultant nozzle ring is included within the overall gas turbine stationary structure and secured by a mounting arrangement which permits relative radial movement at both the inner and outer mountings. A spline-type outer mounting provides circumferential retention. A complete rigid nozzle ring with freedom to "float" radially results. Specific structures are disclosed for the inner and outer mounting arrangements. A specific tie-rod structure is also disclosed for elastically joining the individual nozzle segments. Also disclosed is a method of assembling the nozzle ring subassembly-by-subassembly into a gas turbine employing temporary jacks.

Abstract: Systems and methods for synchronizing a gas turbine-driven generator to an AC power system by employing optimal time control theory to directly drive the turbine-generator to a synchronizing point. The fuel commands, synchronization points, and trajectories are selected in view of the need to minimize thermal stress on the turbine hot-gas-path parts, while also minimizing time required for synchronization. Digital computer and analog implementations are disclosed.

Abstract: Apparatus is disclosed for use in the removal of molten particles from a hot gas. The hot gas carrying the molten particles is passed through a granular bed comprising, in succession, a stack of larger and a stack of smaller solids. Gas exiting the stack of smaller solids is substantially free of the molten particles. The vessel provided for housing the granular bed is adapted to allow the differently sized solids to move in their individual stacks. The vessel includes a single gas entry which is free of louvers or other permanent structural obstructions subject to clogging. The apparatus may be integrated into a coal gasification system or a combined cycle plant where a substantial proportion of the original sensible heat of the gas and of the particles is recovered for other uses.

Abstract: A dovetail of a rotor blade is preferentially remove to thereby modify the support given to the root of a rotor blade. The modified support changes the vibrational characteristics of the rotor blade for reducing the tendency toward crack initiation. In one embodiment of the invention, one or more damping masses are fitted into the dovetail slot within the removed portion of the dovetail. The damping masses are loaded outward against the base of the rotor blade by centrifugal force and frictionally damp some of the vibrational energy of the rotor blade.

Abstract: Dovetail spacers containing slots enable final balancing of a turbine or compressor rotor or wheel without employing grooves or drilling holes in the wheel itself. The spacers are installed in the normal fashion and, when final balancing is performed, appropriate weights are inserted into the slots in selected ones of the spacers. Fine tuning can be performed by drilling or grinding the weights. In one embodiment, the spacer is provided with a radial hole which joins an axial hole. After the turbine or compressor rotor is assembled, additional counterweight material can be added through the radial hole and then be held in place by suitable means such as a setscrew. In this embodiment, weights of suitable material can also be removed as necessary.

Abstract: A shaft vibration evaluator employs measured displacement of a shaft in the vicinity of a bearing together with known or measured shaft eccentricity to calculate the dynamic bearing load so that damaging loads can be avoided. Shaft vibration or motion is assumed to be elliptical having major and minor axes which are inclined at angles with respect to the bearing displacement sensors. The magnitude of the major and minor axes and the angular displacement are calculated from the measured parameters and provide one set of inputs to the load calculator. Bearing eccentricity can be calculated from a knowledge of shaft speed, lubricant temperature and known bearing geometry. For a given eccentricity, a set of four damping coefficients and four spring coefficients of the bearing may be derived. These coefficients are the remaining inputs to the dynamic load calculator.

Abstract: A plurality of flow channels permit a controlled flow of compressed air to flow therein in contact with the flange of a gas turbine combustor transition piece to reduce the operational temperature of the flange and to thereby reduce stress creep distortion of the flange. The flow channels may be disposed in a surface of the flange facing a seal member or in a surface of the seal member facing the flange. In one embodiment, a longitudinal slot in the flange permits the entry of a sealing flange or seal plate. The flow channels may be disposed in the surface of the slot or in the surface of the flange or seal plate. In another embodiment of the invention, the seal member embraces the exterior of the flange and the flow channels may be disposed in either of the facing surfaces.

Abstract: A flameholder arrangement for a gas turbine combustor or the like includes a primary flameholder such as an elongated V-gutter extending across a main flow stream of gaseous components within the combustor. Vortices are shed by the trailing edges of the primary V-gutter flameholder and circulate in essentially two-dimension flow fields in planes normal to the elongated V-gutter to produce a downstream wake. In addition, a plurality of winglets are carried by the primary flameholder and are configured so as to shed vortices rotating about axes generally parallel to the main flow stream. More particularly, the winglets are carried by the outer surfaces of the V-gutter elongated walls, and lie in planes normal to the V-gutter walls and angled with respect to the flow stream. The resultant flow in the wake downstream of the V-gutter is three-dimensional for enhanced mixing of the gaseous components.

Abstract: A combined cycle coal gasification power plant includes a coal gasifier which generates low BTU coal gas for consumption by a gas turbine. Before being applied to the gas turbine, the coal gas is passed through a clean-up system which removes undesirable constituents from the coal gas. Efficient operation of the clean-up system requires that a predetermined discharge pressure of clean coal gas leaving the clean-up system must be maintained. A control system controls the coal gasifier according to either one of the discharge pressure of clean coal gas and the turbine power output requirement while maintaining the clean coal gas discharge pressure and power output at predetermined values.