Abstract: A flow diverter for an air separator of a gas turbine includes a cylindrical body configured to fit within a cooling hole of the air separator. One or more air flow vents are defined through and around a partial circumference of the cylindrical body. A bottom panel closes the cylindrical body at one end. A mounting flange surrounds the cylindrical body at an open end and extends radially outward from the cylindrical body. When the flow diverter is installed, air flows through the open end in a radial direction and exits through the air flow vents in an axial direction. The cylindrical body may include a collapsible region that collapses to engage the air separator and prevent the flow diverter from being dislodged. The air separator may additionally or alternately include supplemental cooling holes in a recessed area proximate to its mounting flange.

Abstract: A flow diverter for an air separator of a gas turbine includes a cylindrical body configured to fit within a cooling hole of the air separator. One or more air flow vents are defined through and around a partial circumference of the cylindrical body. A bottom panel closes the cylindrical body at one end. A mounting flange surrounds the cylindrical body at an open end and extends radially outward from the cylindrical body. When the flow diverter is installed, air flows through the open end in a radial direction and exits through the air flow vents in an axial direction. The cylindrical body may include a collapsible region that collapses to engage the air separator and prevent the flow diverter from being dislodged. The air separator may additionally or alternately include supplemental cooling holes in a recessed area proximate to its mounting flange.

Abstract: A system includes a compressor configured to compress a gaseous stream, an exhaust gas cooler configured to cool an exhaust gas from combustion with a cooling water, and a water injection system configured to inject the cooling water from the exhaust gas cooler into at least one of a compressor inlet of the compressor, a stage of the compressor, between stages of the compressor, or an inlet duct coupled to the compressor inlet of the compressor, or any combination thereof.

Abstract: A bucket for a steam turbine includes an airfoil portion having a radially outer tip, the radially outer tip having a thermal barrier coating applied thereto, and wherein the thermal barrier coating is resurfaced to form at least one ridge along the radially outer tip.

Abstract: Methods and apparatus for operating a combined-cycle power system are provided. The method includes operating the steam turbine, the combustion turbine, and the steam source at steady state operating conditions. Upon sensing a grid frequency deviation away from the standardized grid frequency value, determining a current thermal energy capacity of the steam source, determining a rate of frequency recovery available using the current thermal energy capacity of the steam source and a predetermined rate of change of the at least one steam turbine control valve, if the determined rate of frequency recovery available is greater than the grid frequency deviation, mitigating the frequency deviation using the current thermal energy capacity, if the determined rate of frequency recovery available is less than the grid frequency deviation then mitigating the frequency deviation using the current thermal energy capacity substantially simultaneously with a power level increase of the combustion turbine.

Abstract: Methods and apparatus for operating a combined-cycle power system are provided. The method includes operating the steam turbine, the combustion turbine, and the steam source at steady state operating conditions. Upon sensing a grid frequency deviation away from the standardized grid frequency value, determining a current thermal energy capacity of the steam source, determining a rate of frequency recovery available using the current thermal energy capacity of the steam source and a predetermined rate of change of the at least one steam turbine control valve, if the determined rate of frequency recovery available is greater than the grid frequency deviation, mitigating the frequency deviation using the current thermal energy capacity, if the determined rate of frequency recovery available is less than the grid frequency deviation then mitigating the frequency deviation using the current thermal energy capacity substantially simultaneously with a power level increase of the combustion turbine.

Abstract: A method and apparatus for operating a combined-cycle power system is provided. The system is coupled to an electric power grid. The system includes at least one electric power generator, at least one steam turbine coupled to the generator, at least one combustion turbine coupled to the generator, and at least one steam source that is in flow communication with the steam turbine. The method includes operating the system at a first power output level with the steam turbine and the combustion turbine being synchronized to an operating frequency of the grid, so that the steam turbine, the combustion turbine, and the grid are operating at a frequency substantially similar to a standardized grid frequency value. The method also includes sensing a grid frequency deviation away from the standardized grid frequency value.

Abstract: A method and apparatus for operating a combined-cycle power system is provided. The system is coupled to an electric power grid. The system includes at least one electric power generator, at least one steam turbine coupled to the generator, at least one combustion turbine coupled to the generator, and at least one steam source that is in flow communication with the steam turbine. The method includes operating the system at a first power output level with the steam turbine and the combustion turbine being synchronized to an operating frequency of the grid, so that the steam turbine, the combustion turbine, and the grid are operating at a frequency substantially similar to a standardized grid frequency value. The method also includes sensing a grid frequency deviation away from the standardized grid frequency value.

Abstract: A non-intrusive method of monitoring the integrity of a rotating member comprising mounting at least one sensor in a stationary frame of reference in a casing over the rotating member, measuring the pressure field of the rotating member, comparing the measured pressure field with a corresponding reference pressure field, identifying variations in the measured pressure field, the variations indicative of a fault in the rotating member, and generating an output indicative of an identified fault.

Abstract: A non-intrusive method of monitoring the integrity of a rotating member comprising mounting at least one sensor in a stationary frame of reference in a casing over the rotating member, measuring the pressure field of the rotating member, comparing the measured pressure field with a corresponding reference pressure field, identifying variations in the measured pressure field, the variations indicative of a fault in the rotating member, and generating an output indicative of an identified fault.

Abstract: A method is disclosed for monitoring and controlling a compressor including (a) monitoring at least one compressor parameter; (b) storing data indicative of the monitored parameter in a database system; (c) processing the collected data using a stall precursor detection algorithm to determine a stall precursor; (d) comparing the stall precursor with at least one of a corresponding average compressor value, and a corresponding unit specific value to determine the level of compressor operability, and (e) if the stall precursor varies from at least one of the average compressor value and the unit specific value, performing corrective actions to vary the level of compressor operability to prevent a surge condition.

Abstract: A gas turbine operational strategy is provided for the optimization of ISO-Day rated performance. The invention is realized by setting the nominal operating line equal to or slightly below the operating limit line, so that ISO full load performance is maximized. Thus, the first stage turbine nozzle throat area is sized such that, without inlet bleed heat addition, and at Base-Load pressure ratio and firing temperature, the compressor operates within its operational limits on a ISO day. As ambient conditions change, levels of inlet bleed heat and firing temperature are controlled and the inlet guide vane angle is set whereby the nominal operating line is equal to or slightly below the operating limit line.

Abstract: The surge pressure ratio of a compressor is determined by transiently reducing the inlet flow to the compressor to increase the compressor pressure ratio sufficiently to produce the surge pressure ratio. The reduction in flow of fluid is maintained for a time period insufficient to exceed the exhaust gas temperature limit for the turbine. The area of the first-stage nozzle of the turbine is reduced and the inlet flow to the compressor is reduced to a steady state to achieve pressure ratios, in close proximity to the surge line. By transiently further reducing the inlet flow to the compressor and then increasing the inlet flow back to the steady-state condition, the surge pressure ratio can be obtained without exceeding machine operational limits.

Abstract: In a dynamoelectric machine stator core assembly wherein adjacent packages of stacked laminations are separated by a plurality of radially extending spacer blocks, and wherein each adjacent pair of spacer blocks define in cooperation with adjacent axially spaced laminations, a cooling duct, the improvement comprising a plurality of turbulator elements in each cooling duct, each turbulator element extending into the duct from one of the adjacent axially spaced laminations.