Abstract: A simplified air bleed balancing control system for a pair of aircraft gas turbine engines reduces the number of pressure transducers and differential pressure transducers. Advantages include lower weight, less expensive system, better total system MTBF (mean time before failure), acceptable differential pressure transducer drift identification and compensation by the digital controller, and fewer maintenance tasks.

Abstract: A thermal management system includes at least two of a multiple of heat exchangers arranged in an at least partial-series relationship.

Abstract: A gas turbine engine system. The system includes a compressor with a first compressor stage and a second compressor stage, a turbine with a first turbine stage and a second turbine stage, a first flow path connecting the first compressor stage and the first turbine stage, a second flow path connecting the second compressor stage and the second turbine stage, a crossover flow path connecting the first flow path and the second flow path, and an ejector positioned about the crossover flow path and the first flow path. The ejector may be a variable motive nozzle ejector.

Abstract: A bleed air balancing system includes a plurality of bleed air flow paths (12) each carrying bleed air from one of a plurality of gas turbine engines (10), each bleed air flow path (12) including a flow rate sensor (19), and a circuit (52, 200) outputting at least one flow rate setpoint based on flow rates measured by each of the flow rate sensors (19), wherein each of the plurality of bleed air flow paths (12) includes: a pressure regulating valve (16), a pressure sensor (18), and a controller (20) for controlling the position of the pressure regulating valve (16), the controller (20) including an output (26) connected to the pressure regulating valve (16), a pressure control loop (60) generating a pressure correction signal, and a flow control loop (62) generating a flow correction signal, wherein the controller (20) outputs a control signal (28) on the output (26) based on the pressure correction signal and the flow correction signal. A method of operating the system is also disclosed.

Abstract: An apparatus and method for suppressing dynamic instability in a bleed duct of a gas turbine engine includes a fan bypass duct configured to permit a flow of air through the gas turbine engine. The fan bypass duct defines a fan duct surface, and the bleed duct has an inlet in fluid communication with the fan bypass duct and a flow control valve having an opened position and a closed position. A flow diverter is positioned on the fan duct surface proximate the inlet of the bleed duct and diverts the flow of air from the inlet when the flow control valve is closed, while permitting a portion of the flow of air to enter the inlet when the flow control valve is opened.

Abstract: An exemplary thermal air exhaust system includes circumferentially extending exhaust passages to exhaust thermal control air from an annular region between an outer casing and a distribution manifold encircling an axially extending portion of the casing after the thermal control air has been sprayed on at least one thermal control ring attached to the outer casing and/or onto the outer casing by spray tubes with spray holes. Baffles attached to base panels of the distribution manifold and contoured to form the exhaust passages between the baffles and base panels. The exhaust passages having exhaust passage inlets formed by radially facing exhaust holes through the baffles and exhaust passage outlets formed by circumferentially facing exhaust passage outlets between the baffles and the base panels. Thermal control air is sprayed on at least one thermal control ring and/or onto the outer casing and then circumferentially exhausted through the exhaust passages.

Abstract: A land based gas turbine apparatus includes an integral compressor; a turbine component having a combustor to which air from the integral compressor and fuel are supplied; and a generator operatively connected to the turbine for generating electricity; wherein hot gas path component parts in the turbine component are cooled entirely or at least partially by cooling air or other cooling media supplied by an external compressor. A method is also provided which includes the steps of supplying compressed air to the combustor from the integral compressor; and supplying at least a portion of the cooling air or other cooling media to the hot gas path parts in the turbine component from an external compressor.

Abstract: In a jet engine with compressor air circulation provided for stabilizing the flow conditions, the compressed hot compressor air tapped from the flow path of the compressor (1) is first cooled in the bypass duct (3) and then resupplied to the upstream compressor via line (12). This reduces the thermal load of the blades and improves efficiency.

Abstract: A tip turbine engine includes an axial compressor having a plurality of airfoils compressing core airflow. The airfoils include bleed air openings on their suction side surfaces. The bleed air openings prevent separation of the compressed airflow, which permits each airfoil stage to perform increased compression without separation of the airflow. As a result, the number of stages can be reduced, thereby shortening the overall length of the turbine engine.

Abstract: The invention concerns a precooler (30) having an annular cross-sectional shape about the axis (L-L) of the pod and arranged inside the rear part (10R) of the inner shroud (10) in contact with a cold fluid (9) exiting the fan duct (13).

Abstract: A turbine nozzle includes first and second vanes joined to outer and inner bands. The vanes include outboard sides defining outboard flow passages containing axial splitlines, and opposite inboard sides defining an inboard flow passage without axial splitline. The two vanes include different cooling circuits for differently cooling the inboard and outboard vane sides.

Abstract: The invention is a method for controlling blade tip clearance in a turbine engine having a flowpath extending therethrough, and a system for carrying out the method. The method includes acquiring a first nonpulsating pressure signal PC representative of tip clearance, sensing a second pressure PB substantially unaffected by tip clearance, forming an actual ratio of the acquired pressure and the sensed pressure, determining an error E having an actual component and a desired component, the actual component being a function of the actual ratio; and commanding a clearance control system to reduce the error.

Abstract: Aspects of the invention relate to a system and method for actively controlling compressor clearances in a turbine engine by passing a thermal fluid in heat exchanging relation through a compressor vane carrier. During some operational conditions, such as hot restart or spin cool, it may be desirable to heat the vane carrier to enlarge or at least prevent a decrease in compressor clearances. In such cases, a heated thermal fluid can be provided by reclaiming residual exhaust energy from a heat recovery steam generator. At any condition where improved performance is desired, such as at base load operation, the vane carrier can be cooled to minimize compressor clearances. A cooled thermal fluid can be bleed air from an upstream portion of the compressor, water-cooled high pressure bleed air from a downstream portion of the compressor, or feed water from the bottoming cycle in a combined cycle engine.

Abstract: A turbine overspeed control system for use with a gas turbine engine of a gas turbine electrical powerplant. The overspeed control system preferably comprises a first and second overspeed control subsystem. When an overspeed condition of the gas turbine engine is detected, the first overspeed control subsystem acts to remove air from a combustion section of the engine, while the second overspeed control subsystem operates to alter the angle at which an incoming flow of air is supplied to a compressor turbine located therein. The result of operating the first and/or second overspeed control subsystem is a reduction in the speed of the gas turbine engine that is much more rapid than can be accomplished by simply shutting off a fuel supply thereto.

Abstract: An inlet bleed heat and power augmentation system utilizing a bi-directional and common piping arrangement is disclosed. The piping arrangement includes a plurality of feed tubes arranged to communicate either steam to a compressor discharge plenum or compressed air from the compressor discharge plenum. Various embodiments of the invention are discussed including operation methods.

Abstract: A method of supplying air to a vehicle is provided, wherein the method includes modulating a flow of air from between a fan assembly of a turbofan engine and a high pressure compressor of the turbofan engine with a core driven fan stage coupled in parallel to the high pressure compressor. The method also includes channeling the air from the core driven fan stage to the vehicle.

Abstract: A secondary flow, turbine cooling air system for the uniform cooling of high pressure turbine module components such as the turbine shroud, turbine blade tips, turbine nozzle, transion liner, and turbine bearing support housing in a recuperated gas turbine engine is provided. The secondary flow turbine cooling system provides uniform cooling air having a similar pressure and temperature in a recuperated gas turbine engine as the compressor discharge air of a non-recuperated gas turbine engine. A method for uniform cooling of high pressure turbine module components using the secondary flow turbine cooling air system is also provided.

Abstract: A modular method of modeling a power plant includes selecting a major component module model from a library of component module models for each major component of the power plant, with each major component module representing a power plant major component of a unique configuration. The method also includes inputting initial model information into a database for the selected modules, with the initial model information including at least convergence criteria and a maximum number of passes. The method further includes running the modular model by running each selected module and enabling data exchange between the selected modules.

Abstract: Methods of increasing lifetimes of components in a gas turbine engine. Ordinarily, components are replaced after they experience a certain number of thermal cycles, or a certain operating temperature limit is exceeded. Under one form of the invention, the components are not replaced at that time, but are subjected to increased cooling, which decreases the highest temperature reached in subsequent thermal cycles. Also, many components are replaced when acceleration of an engine falls below a target. In one form of the invention, the components are not replaced, but (1) scheduled fuel flow is increased and (2) compressor stall margin also increased, in order to attain the target acceleration.

Abstract: A gas turbine engine includes a compressor, combustor, and turbine having a row of blades mounted inside a surrounding turbine shroud. A heat exchanger is used for cooling pressurized air bled from the compressor. A distribution network joins the heat exchanger to the turbine for selectively channeling air from the heat exchanger below the blades and above the shroud for controlling blade tip clearance.

Abstract: A method for operating a gas turbine engine includes channeling fluid from a cooling fluid source to a combustor that includes at least one deflector and flare cone. The deflector and flare cone are coupled together and are configured to define a cooling fluid channel therebetween. The flare cone has a plurality of cooling injectors extending therethrough. The plurality of injectors are spaced circumferentially about a centerline axis of the flare cone and are coupled in flow communication with the fluid source. The plurality of injectors has a plurality of first injectors and a plurality of second injectors. The method also includes directing a portion of the fluid through the plurality of first injectors. The method further includes directing a portion of the fluid through the plurality of second injectors, wherein the first plurality of injectors facilitates cooling a portion of the deflector more than the second plurality of injectors.

Abstract: A gas turbine engine includes a turbine rotor and a compressor, which provides discharge air. A nozzle, typically referred to a tangential on-board injector (TOBI), is arranged near the rotor to deliver the discharge air near the turbine rotor for cooling it. The TOBI receives pollution air leaking past seals within the gas turbine engine. The TOBI swirls the discharge air and the pollution air before it reaches the turbine rotor. The TOBI provides multiple passages separated by vanes. At least some of the passages include discharge inlets and outlets for carrying the discharge air from the compressor to the turbine rotor. Typically, several of the passages are unused and blocked. However, the example arrangement provides a pollution inlet and outlet in at least one of the normally unused, blocked passages.

Abstract: A bleed valve (30) for a gas turbine engine (10) comprises a diffuser (50), through which heated compressor bleed air flows (54) into a bypass duct (22) air stream (B), has a plurality of small holes (40). The plurality of holes (40) is divided into two or more arrays of holes (52p,q,r), each array of holes (52p,q,r) is angled (?) away from one another so that their respective bleed flows (54p,q,r) do not coalesce. This separation improves mixing with the air stream (B) and helps prevent hot bleed air damaging nacelle and other engine components.

Abstract: A method for testing a cooling system for use in a gas turbine engine control system is provided. The method includes connecting an inlet of the cooling system to a differential pressure sensor, connecting an outlet of the cooling system to the differential pressure sensor, and determining whether or not a difference in pressure exists between the inlet and outlet, wherein such a pressure difference is indicative of whether cooling fluid is flowing through the cooling system.

Abstract: In a gas turbine electric power generator where rotational speed of the gas turbine is synchronized to the electrical frequency of a power grid and the gas turbine includes a compressor component, an air extraction path, and means for controlling an amount of compressor air extraction, a method is provided for controlling output power produced by a gas turbine. The method includes initiating compressor air extraction and controlling the amount of compressor air extraction.

Abstract: A method and device for improved pressure balancing in a bearing chamber pressurization system for gas turbine engines employ a partition member to substantially separate first and second air-oil seals of the bearing housing.

Abstract: A method of operating a gas turbine engine is provided. The gas turbine engine includes at least one engine casing and at least one rotor assembly. The method includes directing airflow through a supply pipe and into a heat exchanger, lowering the temperature of the airflow in the heat exchanger, and directing the cooled airflow into the engine casing to cool the casing.

Abstract: An intercooler (3) is provided with heat exchanger surfaces (6) and is arranged in the gas stream between two compressors (1, 2) or two compressor stage groups for compressing a gas. An aftercooler (5) is also provided with heat exchanger surfaces (7) and is arranged after the second compressor (2). To utilize the waste heat generated in the coolers (3, 5), the heat exchanger surfaces (6, 7) of the intercooler (3) and of the aftercooler (5) are integrated in a steam generator (9) in such a way that the heat exchanger surfaces are connected with the feedwater pump (40, 59) of the steam generator (9).

Abstract: A gas turbine system comprises a compressor that takes in suction air on the inlet side and compresses it to compressor end air that is available on the outlet side, a combustor in which a fuel is burned by using the compressor end air while resulting in the formation of hot gas, as well as a turbine in which the hot gas is expanded while providing work output. In a method for cooling this gas turbine system, compressed air is removed from the compressor, is fed as cooling air for cooling inside an internal cooling channel through thermally loaded components of the combustor and/or the turbine, is then compressed and added to the compressor end air. An improved cooling without disadvantage for the efficiency of the system is achieved in that, in the manner of a targeted leakage, a small part of the cooling air is fed for film cooling into the turbine stream through drilled film cooling openings provided on the components.

Abstract: A process is provided for the control of the amount of cooling air of a gas turbine set. Suitable means are provided in the cooling system to enable the amount of cooling air to be varied. The control of this means takes place in dependence on an operating parameter (X). This operating parameter is made dependent on the fuel type used.

Abstract: A method and device for decoupling combustor attenuation and pressure fluctuation from turbine attenuation and pressure fluctuation in a gas turbine engine. The engine has: a compressor; a combustor; and a turbine, that generate a flow of hot gas from the combustor to the turbine. An aerodynamic trip is disposed in at least one of; a combustor wall; and an inner shroud of the nozzle guide vane ring, and is adapted to emit jets of compressed air from cross flow ports into the flow of hot gas from the combustor. The air jets from the cross flow ports increase turbulence and equalize temperature distribution in addition to decoupling the attenuation and pressure fluctuations between the combustor and the turbine.

Abstract: A cooling system for a gas turbine engine includes a fuel deoxygenator for increasing the cooling capacity of the fuel. The fuel deoxygenator removes dissolved gases from the fuel to prevent the formation of insoluble deposits. The prevention of insoluble deposits increases the usable cooling capacity of the fuel. The increased cooling capacity of the deoxygenated fuel provides a greater heat sink for cooling air used to protect engine components. The improved cooling capacity of the cooling air provides for increased engine operating temperatures that improves overall engine efficiency.

Abstract: A system located with the housing of a gas turbine engine for increasing the pressure of working fluid from the compressor that will be utilized to cool a component. In one form the system includes a pump rotatable with a turbine component to increase the pressure of the working fluid.

Abstract: A gas turbine engine system having improved thermal efficiency, which comprises: (1) an inlet air stream; and (2) a dry low emissions combustor assembly having an air inlet for receiving the inlet air stream, at least one bleed air port and an air outlet for discharging at least a portion of the received air from the inlet air stream. This system includes a source of warmer air capable of raising the ambient temperature of the inlet air stream received by the air inlet of the dry low emissions combustor assembly while operating at a partial load until the system reaches a new equilibrium state having improved thermal efficiency. Also disclosed is a method for improving the thermal efficiency of the dry low emissions combustor assembly, which comprises the step of including a source of warmer air with the inlet air stream received by the air inlet of the dry low emissions combustor assembly while operating at a partial load until the system reaches a new equilibrium state having improved thermal efficiency.

Abstract: A method and apparatus for dumping surge bleed air into a primary nozzle of a free gas turbine engine. The surge bleed air is introduced into gas turbine exhaust flow within the primary nozzle to create a mixed flow which may be used as a combined driver flow to compensate for reduced engine exhaust flow during periods when operation of the turbine engine may be exclusively dedicated to only electric load operation. The surge bleed air may not be the educted flow or the secondary driven flow, while cooling air passing through an oil cooler may be an educted flow. Surge bleed air may flow through, for example, mixer lobes, hollow struts, or the center body before mixing with the gas turbine exhaust flow.

Abstract: An apparatus and method is provided for improving efficiency of a transonic gas turbine engine compressor by bleeding off a shockwave-induced boundary layer from the gas flow passage of the compressor using an array of bleed holes having a downstream edge aligned with a foot of an oblique shock wave which originates on the leading edge of an adjacent transonic rotor blade tip.

Abstract: An auxiliary power unit (APU) inlet muff anti-icing system that uses high pressure, high temperature APU compressor delivery air to melt any accumulation of ice and snow near the bottom of the muff with a tracer line coupled to a perforated gull wing fairing mounted within the inlet muff and that uses the compressor delivery air as the primary stream for an ejector to suck ice and snow melt accumulating near the fairing overboard.

Abstract: A gas turbine includes a compressor, a combustor, a turbine, and a flow path diverting an excess portion of the compressed air produced by the compressor around the turbine. The flow path conducts the excess portion into a turbine exhaust gas flow producing a cooled exhaust gas. A method of operating the gas turbine includes opening an inlet guide vane of the compressor to allow the compressor to produce an increased volume of compressed air. The increased volume exceeds a volume of compressed air needed to support combustion. An excess portion of the compressed air is directed into the exhaust gas to produce a cooled exhaust. In a combined cycle power plant, the cooled exhaust from the gas turbine may be used to warm a steam turbine portion to a desired temperature while allowing operation of the gas turbine at a power level that produces exhaust gas at a temperature higher than the desired temperature.

Abstract: A gas turbine engine having a longitudinal centerline axis therethrough, including: a fan section at a forward end of the gas turbine engine including at least a first fan blade row connected to a first drive shaft; a booster compressor positioned downstream of and in at least partial flow communication with the fan section including a plurality of stages, each stage including a stationary compressor blade row and a rotating compressor blade row connected to a drive shaft and interdigitated with the stationary compressor blade row; a core system positioned downstream of the compressor, where the core system further includes an intermediate compressor positioned downstream of and in flow communication with the booster compressor, the intermediate compressor being connected to a second drive shaft, and a combustion system for producing pulses of gas having increased pressure and temperature from a fluid flow provided to an inlet thereof so as to produce a working fluid at an outlet; and, a low pressure turbine

Abstract: Aspects of the invention relate to methods and assemblies for improving the efficiency of a turbine engine through active management of blade tip clearances. In some designs, a portion of compressor exit air is routed to the rotor and discs of the turbine section. Aspects of the invention relate to treating the compressor exit air in light of the operating conditions of the engine. For instance, under base load or substantially steady state operation, a portion of compressor exit air can be routed to the rotor and discs without reducing the temperature of the compressor exit air. In such case, blade tip clearances will reduce, allowing for improved engine efficiency. Under part load or substantially transient operating conditions, a portion of compressor exit air can be cooled before it is supplied to the rotor and discs. As a result, the blade tip clearances increase, minimizing concerns of blade tip rubbing. Routing of the compressor exit air for cooling and bypass can be controlled by a valve.

Abstract: A gas turbine engine having a longitudinal centerline axis therethrough, including: a fan section at a forward end of the gas turbine engine including at least a first fan blade row connected to a drive shaft; a booster compressor positioned downstream of the fan section including a plurality of stages, where each stage includes a stationary compressor blade row and a rotating compressor blade row connected to the drive shaft and interdigitated with the stationary compressor blade row; and, a combustion system for producing pulses of gas having increased pressure and temperature of a fluid flow provided to an inlet thereof so as to produce a working fluid at an outlet.

Abstract: A pressure reduction apparatus is disclosed. Air at high pressure and temperature may be drawn from a source such as a bleed valve of a gas turbine engine that supplies the air to an airplane interior. The air is passed to a pressure reduction vessel. The vessel has sufficient volume such that the high pressure air, upon entering the vessel, will reduce in temperature and pressure. The pressure reduction apparatus allows the air to depressurize and drop in temperature to near ambient conditions. Upon exiting the pressure reduction apparatus, the air is at a temperature and pressure sufficient to allow the air to be sampled and analyzed by conventional equipment used for testing for airborne impurities such as semivolatile compounds ad particulates.

Abstract: Aspects of the invention relate to a turbine engine system and method for actively managing blade tip clearances during part load operation of the engine. Aspects of the invention relate to extracting a portion of the combustion gases from the combustor section of the engine and routing these heated gases to the blade rings or other stationary structure surrounding the turbine blades. Upon exposure to the combustion gases, which can be mixed with compressor exit air, the stationary structure will thermally expand, causing blade tip clearances to increase. Thus, concerns of blade tip rubbing are minimized. Once the engines achieves steady state operation, the flow of the combustion gases to the blade rings can be substantially restricted so that only compressor exit air is supplied to the stationary structure. Consequently, the stationary structure will contract and the blade tip clearances will decrease, thereby increasing the efficiency of the turbine.

Abstract: A system for controlling blade tip clearance in a turbine. The system includes a stator including a shroud having a plurality of shroud segments and a rotor including a blade rotatable within the shroud. An actuator assembly is positioned radially around the shroud and includes a plurality of actuators. A sensor senses a turbine parameter and generates a sensor signal representative of the turbine parameter. A modeling module generates a tip clearance prediction in response to turbine cycle parameters. A controller receives the sensor signal and the tip clearance prediction and generates at least one command signal. The actuators include at least one actuator receiving the command signal and adjusts a position of at least one of the shroud segments in response to the command signal.

Abstract: A multi-position pressurized fluid actuator is mounted for movement in a casing. The actuator includes at least one selectively openable opening at a location corresponding to an intermediate position through which pressurized fluid can be selectively bled from the actuator to permit the actuator to remain in the intermediate position.

Abstract: A method of balancing the supply of bleed air from a plurality of gas turbine engines, there being an air bleed line from each of the engines to a common distribution line which distributes the bled air to at least one ancillary system, each air bleed line including a control valve which is controllable by a controller to vary the flow rate of air bled from the associated engine, the method including providing to the controller a demand signal indicative of the demand for bleed air by the ancillary system, sensing air pressure in the distribution line and comparing the demand signal with the sensed air pressure to derive a command signal, flow rates the air pressure individually in each of the air bleed lines from the engines with respective air flow rate sensors which provide air flow rate signals to the controller, comparing the air flow rates in each of the air bleed lines to derive individual flow matching signals for each of the engines, comparing each of the flow matching signals to the command signal t

Abstract: Bleeding is operated by annularly providing plural stationary blades at an interior side of a vehicle; annularly providing plural moving blades around rotor disk adjacent to stationary blades; providing plural stage units comprising the stationary and moving blades; introducing bleed air into each stage unit from a compressor; supplying bleed air extracted from a final stage of the compressor into a first stage unit; and supplying bleed air extracted from compressed air which has not yet arrived at a final stage unit of the compressor.

Abstract: A gas turbine engine includes a compressor powered by a turbine. The turbine includes a nozzle having vanes extending between outer and inner bands. Each vane includes an internal cooling plenum and a bypass tube extending through the bands. First and second manifolds surround the outer band and are disposed in flow communication with the plenums and bypass tubes, respectively. A bleed circuit joins the compressor to the manifolds for providing pressurized air thereto. A control valve modulates airflow to the first manifold and in turn through the cooling plenums of the vanes.

Abstract: The invention relates to a method of supplying cooling air to the hot portions of a turbojet that comprises, from upstream to downstream: a compressor; a diffuser; a combustion chamber; a distributor; and a turbine driving said compressor, in which method a flow of air is bled from the flow of air delivered by the compressor, the bled-off flow is cooled in a heat exchanger situated radially outside the combustion chamber, and is then directed radially inwards via the stationary blades of the distributor and used for cooling the moving wheel of the turbine, the method wherein the flow of cooling air is bled from the zone of the end of the combustion chamber that surrounds the diffuser, and wherein the stationary blades of the distributor are also cooled by a second flow of air bled from the diffuser.

Abstract: A gas turbine including a compressor, combustor and turbine further includes (1) a cooling air system for supplying part of air compressed by a compressor to a high temperature section of the turbine, (2) a heat exchanger for exchanging heat of part of air compressed by the compressor, this heat exchanger being mounted on the cooling air system, and (3) a system for adjusting the air temperature downstream from the heat exchanger in conformity to the operation period of the turbine.