Abstract: Method of operating a wind turbine in response to a wind speed, the wind turbine having at least a rotor with a plurality of blades and a generator comprising a generator rotor and a generator stator, the method comprising, at wind speeds above a first wind speed, increasing the pitch angle of the blades and reducing the rotor speed with increasing wind speed, said first wind speed being superior to the nominal wind speed; wherein at a second wind speed, the speed of the generator rotor is equal to the synchronous generator rotor speed, said second wind speed being superior to said first wind speed; and wherein at wind speeds superior to said second wind speed, the speed of the generator rotor is lower than the synchronous generator rotor speed.

Abstract: A centrifugal compressor includes a compressor housing, an impeller wheel which compresses intake gas from an intake-air inlet, a plurality of guide vanes disposed circumferentially along an inner circumferential wall of the intake-air channel between the intake-air inlet and the impeller wheel to swirl the intake gas around the rotational axis, a central intake-air flow path formed at an inner side of the guide vanes to allow the intake gas to flow to the impeller wheel without passing through the guide vanes, and a guide-vane moving mechanism which simultaneously changes the inclination angle of the guide vanes. Guide vanes generate swirl flow at an inner circumferential housing portion of an impeller wheel to improve a surge margin and to restrict decrease in a choke flow rate.

Abstract: A turbine wheel for low-pressure ratio applications is disclosed. The ratio of the outlet area of the wheel (A2) to the inlet area of the wheel (A1) is less than approximately 0.4. In an embodiment, the wheel is a radial or mixed-flow wheel.

Abstract: There is provided an impeller rotating about a rotary shaft, the impeller including: an inlet through which a fluid is introduced; an outlet through which the fluid is discharged; a supporter connected to the rotary shaft; a blade portion provided on the supporter; a shroud portion disposed to cover the blade portion; and a sealing portion including at least one sealing protrusion protruding in a direction that is in parallel with the rotary shaft, and disposed at a portion of the shroud portion, which configures the inlet.

Abstract: A fan for a turbofan gas turbine engine having a low hub-to-tip ratio is disclosed. The fan includes a rotor hub and a plurality of radially extending fan blades. Each fan blade defines a hub radius (RHUB), which is the radius of the leading edge at the hub relative to a centerline of the fan, and a tip radius (RTIP), which is the radius of the leading edge at a tip of the fan blade relative to the centerline of the fan. The ratio of the hub radius to the tip radius (RHUB/RTIP) is less than 0.29. In a particular embodiment, this ratio is between 0.25 and 0.29. In another particular embodiment, this ratio is less than 0.25.

Abstract: A lightning current transfer unit (100) for a wind turbine, the lightning current transfer unit (100) comprising a first portion (20a) configured to be electrically coupled to an electrically conducting portion of a blade of a wind turbine electrically connected to a down conductor of the blade and a second portion (20b) configured to be electrically coupled to an electrically conducting portion of a nacelle of the wind turbine connected to a down conductor connected to earth. The first portion (20a) and the second portion (20b) are both independently movable to maintain electrical coupling to the electrically conducting portion of the blade and nacelle respectively. A lightning current transfer portion (104) is provided that comprises a spark gap (106) formed between an electrical connection (108) to the first portion (20a) and an electrical connection (110) to the second portion (20b). The electrical connections (108, 110) are moveable with their respective first or second portion (20a, 20b).

Abstract: The invention relates to a method and control system to control the speed of a centrifugal compressor operating within a vacuum pressure swing adsorption process to avoid an operation at which surge can occur and directly driven by an electric motor that is in turn controlled by a variable frequency drive. The claimed method determines the optimal speed for operation of the compressor along a peak efficiency operating line of a compressor map thereof. Speed of the compressor is adjusted by a feed back speed multiplier when the flow or other parameter referable to flow through the compressor is below a minimum and a feed forward multiplier during evacuation and evacuation with purge steps that multiplies the feed back multiplier to increase speed of the compressor and thereby avoid surge.

Abstract: The subject matter of this specification can be embodied in, among other things, a method that includes receiving one or more surge value parameters, selecting a first value from a selected parameter of the one of the parameters, determining a moving average, determining a rate of change, identifying a first phase of a surge cycle based on determining that the rate of change exceeds a threshold rate change, memorializing the first value, the moving average value, and a first time index, receiving a second value of the selected parameter, identifying a second phase of the surge cycle, receiving a third value of the selected parameter, identifying a third phase of the surge cycle, and providing an indication that one or more compressor surge cycles have occurred.

Abstract: A compressor system includes a compressor train including two or more compressors connected in series and a control mechanism. The control mechanism is controlled by a performance controller. The performance controller is operable to identify a process variable of the performance controller; receive, on a recurrent basis from a load sharing controller, a setpoint for the process variable of the performance controller; and control the control mechanism based on the setpoint and the process variable of the performance controller. The setpoint is determined dynamically during operation of the two or more compressors by the load sharing controller based on a load sharing parameter associated with the two or more compressors.

Abstract: The present invention relates to an acoustic noise monitoring system for a wind turbine, comprising: a microphone for monitoring acoustic noise, the microphone adapted to be mounted to the exterior of a wind turbine nacelle; an input, the input adapted to receive operating conditions data from a wind turbine; a processor, the processor adapted to receive data from the microphone and the input; and storage memory, adapted to store the acoustic noise data and the operating conditions data. The processor is adapted to apply a transfer function to said acoustic noise data to correlate said data with a set of acoustic noise data measured at a remote location from the wind turbine. The system may comprise a controller adapted to generate a control signal, for outputting to a wind turbine controller, for adjusting the operating parameters of the wind turbine in dependence on said correlated data.

Abstract: A cooling fan shroud for an internal combustion engine has a fan port including a fixed cylindrical segment and a movable cylindrical segment mounted by a hinge. A pivot plate on the movable cylindrical segment is compressed with a base plate on a shroud main body so that a loading rib on one plate provides a frictional resistance. A dual-position locking mechanism retains the movable cylindrical segment in an extended position or a retracted position. The mechanism is comprised of a tab extending from the movable cylindrical segment and a ratchet pocket in the main body receiving the tab, wherein the ratchet pocket has a pair of stop notches separated by a deflector rib. The movable cylindrical segment is bendable to allow the tab to ride over the deflector rib in response to a predetermined pivot force applied to the movable cylindrical segment.

Abstract: A system and method are provided for a variable speed compressor with a control module that controls an operating frequency of the variable speed compressor. The control module stores a prohibited frequency range that includes a resonant frequency of the variable speed compressor and an allowed upper frequency above the prohibited frequency range and an allowed lower frequency below the prohibited frequency range. The control module determines a requested frequency and operates the variable speed compressor at the allowed upper frequency for an upper frequency operating time and at the allowed lower frequency for a lower frequency operating time when the requested frequency is within the prohibited frequency range. The control module determines the upper frequency operating time and the lower frequency operating time such that a time-averaged frequency output over the upper frequency operating time and the lower frequency operating time corresponds to the requested frequency.

Abstract: A centrifugal compressor for a turbocharger includes an inlet-adjustment mechanism in an air inlet for the compressor, operable to move between an open position and a closed position in the air inlet. The inlet-adjustment mechanism includes a variable-geometry conduit comprising a plurality of vanes that in the closed position collectively form a converging inlet member having a trailing edge inner diameter that is smaller than an inner diameter of the shroud surface of the compressor housing at the inducer portion of the compressor wheel such that an effective diameter of the air inlet at the inducer portion is determined by the trailing edge inner diameter of the variable-geometry conduit. The vanes in the open position are pivoted radially outwardly so as to increase the trailing edge inner diameter of the inlet member and thereby increase the effective diameter of the air inlet at the inducer portion.

Abstract: A gas turbine engine according to an example of the present disclosure includes, among other things, a fan, a turbine section having a fan drive turbine rotor, and a compressor rotor. A gear reduction is configured to effect a reduction in a speed of the fan relative to an input speed from the fan drive turbine rotor. Each of the compressor rotor and the fan drive turbine rotor includes a number of blades in each of a plurality of blade rows. The number of blades are configured to operate at least some of the time at a rotational speed.

Abstract: In certain embodiments, a system includes a controller configured to obtain an inter-stage pressure measurement between stages of a multi-stage compressor. The controller is also configured to identify actual damage in the multi-stage compressor based at least in part on the inter-stage pressure measurement.

Abstract: The present disclosure is directed to a system and method for protecting a rotary machine in a high noise environment. In one embodiment, the method includes a step of measuring a vibration signal during operation of the rotary machine. Another step includes modulating the vibration signal at a desired frequency to generate a modulated signal having a direct current (DC) value. The desired frequency varies as a function of an operational parameter of the rotary machine. The method also includes a step of filtering the modulated signal via one or more low-pass filters. Another step includes comparing an amplitude of the filtered signal to a threshold amplitude for one or more components of the rotary machine. The threshold amplitude is indicative of an imbalance within one or more components of the rotary machine. The rotary machine is then operated based on the comparison so as to protect the rotary machine from damage caused by the imbalance within the one or more components of the rotary machine.

Abstract: A guide vane is disclosed. The guide vane includes a button, a trunnion connected to the button, and an airfoil connected to the button. The airfoil includes an overhang portion wherein the overhang portion extends from one end of the button to a distal end of the airfoil. The guide vane includes a button corner located near the beginning of the overhang portion. The guide vane includes a variable fillet extending into the overhang portion. The variable fillet includes sections of different radiuses along the length of the fillet.

Abstract: An anti-surge system capable of anticipating a surge event in a compressor for readying the actuator to quickly actuate the anti-surge valve from the closed position to the open position. The control system includes a compressor surge controller configured to transmit a signal to the valve positioner when the operating point of the valve is approaching the surge control line. The compressor surge controller may monitor an operating margin equal to the difference between the operating point and the surge control line, and when the operating margin falls below a prescribed threshold, the compressor surge controller may send a signal to the positioner. In turn, the positioner may vent some pressure from the actuator. In this way, the dead time of the anti-surge valve on the valve seat is minimized and the valve will react more promptly to an opening signal.

Abstract: Systems and methods for preventing excessive loading on a wind turbine are disclosed. The method includes: measuring an actual wind parameter upwind from the wind turbine using one or more sensors; providing the measured wind parameter to a processor; providing a plurality of wind turbine operating data to the processor; utilizing the plurality of operating data to determine an estimated wind turbine condition at the wind turbine; generating a control wind profile based on the actual wind parameter and the estimated wind turbine condition; and, implementing a control action based on the control wind profile to prevent excessive loading from acting on the wind turbine.

Abstract: A bladed rotor for a turbomachine, in particular a gas turbine, having a plurality of blades distributed around the circumference thereof; the blade distribution being made up of a natural-number sector count of first angular sectors and second angular sectors; a first blade count of first blades being arranged in the first angular sectors, and a second blade count of second blades being arranged in the second angular sectors, said second blade count being different from said first blade count; and the sector count being odd (Z=2n+1, n=1, 2, 3, . . . ) and/or greater than two (Z>2).

Abstract: Systems and methods are provided for reducing surge in a boosted engine system. One method comprises adjusting an opening of a compressor recirculation valve to allow a compressor recirculation flow based on a combination of a nominal compressor recirculation flow and a filtered nominal compressor recirculation flow. The nominal compressor recirculation flow may be calculated as a difference between a desired compressor flow rate based on a surge limit of compressor and an estimated throttle mass flow rate.

Abstract: A vane segment according to the present invention includes: an outer connection member connecting a plurality of vanes; positioning jigs for positioning end vanes located at both ends, of the plurality of vanes; and radial restriction sections which restrict the outer connection member so as to be relatively immovable to an outer side in a radial direction of a vane ring, wherein: each of the plurality of vanes has a vane main body and an outer shroud; grooves are formed in the outer shrouds; openings into each of which the positioning jig is inserted are formed in portions of the outer connection member; holes into each of which the positioning jig inserted in the opening is inserted are formed in bottoms of the grooves of the two end vanes; and at least one of the positioning jigs is an eccentric positioning jig.

Abstract: There is provided a method for recovering hydrocarbon compounds from a gaseous by-products generated in the Fisher-Tropsch synthesis reaction, the method comprising a pressurizing step in which the gaseous by-products are pressurized, a cooling step in which the pressurized gaseous by-products are pressurized to liquefy hydrocarbon compounds in the gaseous by-products, and a separating step in which the hydrocarbon compounds liquefied in the cooling step are separated from the remaining gaseous by-products.

Abstract: Methods and systems are provided for adapting a compressor surge line in real-time. In one example, a method may include retarding a surge line in response to a number of surge events greater than a threshold number of surge events, and advancing the surge line in response to a number of aggressive tip-out events, that do not result in surge, greater than a threshold number of tip-out events.

Abstract: A method for enhancing one or more performance parameters of a gas turbine having at least one row of clocked airfoils may generally include choosing a first, a second and a third row of airfoils where the third row is clocked relative to the first row. An unsteady computational fluid dynamics model may be used to determine at least one wake parameter of a working fluid flowing from the second row of the airfoils to the third row of the airfoils. At least one design parameter of the airfoils of the second row may be modified, and the unsteady computational fluid dynamics model may then be used to determine the effect of the airfoil design parameter modification on the at least one wake parameter. The effect on the wake parameter may be compared to a predetermined target range.

Abstract: An electronic apparatus includes a thermopile array sensor, a reflector, and a temperature detection unit. The thermopile array sensor includes a plurality of thermopile elements arranged in a two-dimensional array pattern and a temperature detection surface divided into a plurality of predetermined regions aligned in vertical and horizontal directions, and the thermopile elements output a temperature detection signal corresponding to a temperature of the respective predetermined regions. The reflector is set at an angle to reflect infrared light emitted from a measurement point located outside of a viewing angle of the thermopile array sensor, so as to allow the infrared light to be incident on the temperature detection surface. The temperature detection unit detects the temperature on the basis of the temperature detection signal outputted from each of the thermopile elements. The thermopile array sensor and the reflector are located inside the electronic apparatus.

Abstract: Systems and methods are provided for compressing a cryogenic fluid using a multi-stage compressor. Coolant in a first coolant loop cools cooling jackets of the compression stages and/or inter-stage heat exchangers and warms a pre-compression heat exchanger. The temperature of the coolant in the first heat exchanger is moderated by ambient-air heat exchange. The process fluid is electively cooled by one of the interstage heat exchangers after each of the compression stage if the temperature of the process fluid is above a temperature criterion. This enables the system to operate through a transient period (cool down period) without venting process fluid. The interstage heat exchangers are preferably bypassed when the system reaches steady-state operating temperature.

Abstract: An exhaust diffuser comprising an inner boundary and an outer boundary forming an annular gas path, and a plurality of strut structures extending radially within the gas path. Each of the strut structures include pressure and suction side walls, and a plurality of radially spaced flow injectors are formed in at least one of the pressure and suction side walls for injecting a fluid flow into the gas path adjacent to the strut structure. At least two fluid supply conduits provide a fluid flow to respective radially spaced flow injectors, and a flow control device is associated with each of the conduits to independently control a fluid flow from a fluid source to each of the radially spaced flow injectors.

Abstract: A turbocharger has a turbine housing formed with a coolant inlet channel and a coolant outlet channel. The turbine housing contains a coolant separating region in which delivered coolant is separated and a coolant combining region in which coolant is combined again. Each of the coolant separating region and the coolant combining region is equipped with a conical conducting body.

Abstract: Embodiments of the invention relate generally to turbomachines and, more particularly, to the positioning of airfoils to reduce pressure variations entering a diffuser. One embodiment includes a turbomachine comprising a diffuser, a plurality of airfoil rows, including a first airfoil row adjacent the diffuser, the first airfoil row being of a first type selected from a group consisting of stationary vanes and rotating blades, a second airfoil row adjacent the first airfoil row, the second airfoil row being of a second type different from the first type, and a third airfoil row of the first type adjacent the second airfoil row, wherein at least one of the plurality of airfoil rows is clocked, relative to another airfoil row of the turbomachine, reducing variations in airflow circumferential pressure at at least one spanwise location in the diffuser adjacent the first airfoil row in an operative state of the turbomachine.

Abstract: Provided is a method of controlling a compressor system including measuring variables for generating a performance curve of a compressor, calculating changing rates of the variables; comparing the calculated changing rates with preset changing rate variations; and determining a surge control line different from a preset surge control line according to the calculated changing rates if the calculated changing rates are out of ranges of the preset changing rate variations.

Abstract: A start control unit for a steam turbine plant, wherein inputting a measured value of a steam temperature fed to a steam turbine, a measured value or an estimated value of a rotor temperature of the steam turbine, and a measured value of a casing temperature of the steam turbine, and controlling a steam flow rate so as to increase the steam flow rate fed to the steam turbine when a difference between the steam temperature and the rotor temperature is smaller than a first regulated value and a difference between the rotor temperature and the casing temperature is a second regulated value or larger.

Abstract: A method and apparatus controls a compressor, where the compressor inlet gas may contain water and/or non-aqueous liquid. The method includes the steps of measuring temperature at the compressor inlet and/or outlet side, measuring pressure at the compressor inlet and outlet side in order to determine a compressor pressure ratio, measuring fluid mixture density at the compressor inlet and/or outlet side, measuring individual volume fractions of gas, water and non-aqueous liquid at the compressor inlet and/or outlet side, measuring fluid velocity at the compressor inlet and/or outlet side, and determining individual flow rates of gas, water and non-aqueous liquid on the basis of the measured individual volume fractions of gas, water and non aqueous liquid and the fluid velocity at the compressor inlet and/or outlet side.

Abstract: A system for removing molten metal from a vessel is disclosed. The system includes a pump and a refractory casing that houses the pump. As the pump operates it moves molten metal upward through an uptake section of the casing until it reaches an outlet wherein it exits the vessel. The outlet may be attached to a launder. Another system uses a wall to divide a cavity of the chamber into two portions. The wall has an opening and a pump pumps molten metal from a first portion into a second portion until the level in the second portion reaches an outlet and exits the vessel.

Abstract: A method of operating a wind turbine and a wind turbine employing this method are provided. The method includes measuring an operating temperature in a plurality of components of the wind turbine yielding a plurality of measured operating temperatures. Each measured operating temperature is subtracted from a predefined maximum allowable operating temperature for the corresponding component of the wind turbine thereby yielding a plurality of operating temperature margins. A minimum operating temperature margin among the plurality of operating temperature margins is determined and at least one operating parameter of the wind turbine is set in accordance with the minimum operating temperature margin.

Abstract: The present application provides a wet gas compression system for a wet gas flow having a number of liquid droplets therein. The wet gas compression system may include a pipe, a compressor in communication with the pipe, and a thermoacoustic resonator in communication with the pipe so as to break up the liquid droplets in the wet gas flow.

Abstract: A standard for supporting a turbine rotor and a turbine shell includes a bearing block including a housing enclosing bearing surfaces engageable by the turbine rotor. Turbine shell-arm supports are located on opposite sides of the housing, the turbine shell-arm supports each having a horizontal and one or more vertical surfaces adapted to be engaged by support arms of a turbine shell enclosing at least a portion of the turbine. An internal cooling/heating circuit is arranged to simultaneously cool or heat the bearing block and the turbine shell-arm supports to thereby reduce differential thermal growth characteristics of the turbine rotor and turbine shell.

Abstract: A thrust reverser for a nacelle of a turbojet engine includes deflecting cascades and an external cowl which translates from a closure position to an opening position by a set of control cylinders being attached by their ends to the external cowl. The deflecting cascades are supported by a front frame and a rear frame respectively and are enclosed in an envelope formed by a fan carter and by a fan cowl. The thrust reverser further includes a lock which is able to connect or disconnect the deflecting cascades to the external cowl. When the lock is unlocked, the set of control cylinders translate the external cowl alone in downstream direction while in the lock position, the control cylinders translates the external cowl and the deflecting cascades together in downstream direction.

Abstract: A method of in situ calibrating load sensors of a horizontal axis wind turbine is described. The method comprises the steps of: a) determining a rotor azimuth angle of a first wind turbine blade, b) determining a pitch angle of the first wind turbine blade, c) measuring loads in a first cross-section of the first wind turbine blade using the first load sensors, d) calculating theoretical loads based on at least the rotor azimuth angle and the pitch angle of the blade determined in steps a) and b), e) comparing the loads measured in step c) with the theoretical loads calculated in step d), and f) calibrating the first load sensors based on the comparison of step e), wherein the calibration are based only on measurements carried out, when the generator is cut out.

Abstract: A computer-implemented method of operating a wind turbine park including operating wind turbines includes recording a plurality of sound pressure measurements of the wind turbine park, thereby generating a sound recording. The method also includes calculating values for a plurality of acoustic features associated with the sound recording. The method further includes determining a relationship between the calculated values for the plurality of acoustic features and modeled acoustic features values resident within a probabilistic auditory model of the wind turbine park. The method also includes distinguishing a first contribution to the sound recording originating from the at least one operating wind turbine from a second contribution to the sound recording originating from non-wind turbine sources based on the determined relationship.

Abstract: A fluid stabilizing control method of an axial compressor is provided, which includes driving to drive the axial impeller, and stall controlling to suppress or prevent an occurrence of a stall that may transpire during rotation of the axial impeller by supplying highly-pressurized compressed air into the casing through a stall controller according to a predetermined time and volume. Accordingly, a stall may be suppressed or prevented, the occurrence of a stall that may transpire when a threshold point is exceeded by an unexpected event during driving in a low-flow high-pressure section on a performance curve, in which efficiency is high. Additionally, since an air injection method for suppressing the stall is properly applied, an amount of power expended for the stall control may be reduced while supply of the high-pressure compressed air is minimized, thereby achieving economically feasible stall control.

Abstract: To provide a method of controlling a turbine equipment and a turbine equipment capable of carrying out a starting operation of controlling a load applied to a speed reducing portion while complying with a restriction imposed on an apparatus provided at a turbine equipment. The invention is characterized in including a speed accelerating step (S1) of increasing a revolution number by driving to rotate a compressing portion and a turbine portion by a motor by way of a speed reducing portion, a load detecting step (S2) of detecting a load applied to the speed reducing portion by a load detecting portion, and a bypass flow rate controlling step (S3) of increasing a flow rate of a working fluid bypassed from a delivery side to a suction side of the compressing portion when an absolute value of the detected load is equal to or smaller than an absolute value of a predetermined value and reducing the flow rate of the bypassed working fluid when equal to or larger than the absolute value of the predetermined value.

Abstract: A compressor unit for processing a working fluid comprising a compressor inside a housing to compress the working fluid wherein a collection chamber is fluidly coupled with a working fluid inlet of said housing.

Abstract: A method for producing work from heat including mixing a first working fluid F1 vapor with a second working fluid F2 vapor to form a third working fluid F3; atomizing and/or vaporizing a liquid into the third working fluid F3 to define a saturated working fluid; and expanding the saturated working fluid to perform useful work. A high pressure F1(2) portion of the first working fluid F1 may be expanded prior to the mixing step while the F2 vapor is compressed prior to the mixing step. The steps of compressing the F2 vapor and expanding the high pressure F1(2) portion of the first working fluid F1 may be carried out by an integral compressor and expander assembly (204/209). The integral compressor and expander assembly (204/209) may be positioned within a combined mixer assembly (300) with an internal mixing chamber (206) and outlets (375, 351) of both the compressor (204) and expander (209) are directed toward the mixing chamber 206.

Abstract: Methods, devices and systems capable of performing a hot restart of a compressor driven by a turbine are provided. The turbine has a high speed shaft and a low speed shaft connected to the compressor. A base slow roll speed at which a speed of the low speed shaft is in a slow roll range is maintained at the high speed shaft for a predetermined time. Then, when a vibration amplitude of the compressor is larger than a vibration limit, the maintaining is repeated. Otherwise, a set speed of the high speed shaft is increased, until a current speed of the low speed shaft reaches a minimum operating speed. If, while increasing the set speed, the vibration amplitude becomes larger than the vibration limit, the maintaining is repeated.

Abstract: A seal configuration includes a housing and a rotatable member rotationally mounted relative to the housing. The rotatable member has at least one portion defining an outer perimetrical face that is configured to contact the housing during operational conditions that cause a radial dimension of the at least one portion to increase. The at least one portion has opposing axial surfaces with each of the opposing axial surfaces being dimensionally axially nearer to the other of the opposing axial surfaces immediately radially inwardly of the outer perimetrical face than a furthest part of the outer perimetrical face.

Abstract: A method for obtaining an estimate for a process quantity of a turbomachine comprises measuring (301) first process quantities and calculating (302) an estimate for a second process quantity, for example mass flow, on the basis of the measured first process quantities and a reference table of interrelations between process quantities prevailing in reference inlet conditions corresponding to a pre-defined inlet fluid temperature, a pre-defined inlet fluid pressure, and pre-defined fluid properties at the inlet. The reference table and the measured first process quantities represent such a set of data values that the estimate is obtainable on the basis of different sub-sets of the data values. Hence, the estimation task is over-posed in the sense that there is more data than necessary for obtaining the estimate. In the calculation of the estimate, more weight is given to such a part of the data which has a smaller error contribution.

Abstract: A wind turbine apparatus includes a shaft carrying a plurality of rotor wheels fixed at axially spaced intervals. Each rotor wheel includes buckets at the periphery thereof. First and second generally cylindrical housing are disposed in concentric relationship to define a blind annular chamber surrounding the rotor wheels that directs ambient winds to through the inner wall of the inner cylindrical housing to the periphery of the respective rotor wheels. One extremity of the blind annular chamber is open for receiving ambient air flow and a second axial extremity proximate is closed, whereby axial airflow into the annular chamber is substantially directed in a radial direction toward the buckets carried on the rotor wheels to cause rotation of the shaft.

Abstract: Methods and devices for performing a model based anti-surge dead time compensation in systems including a compressor and an anti-surge loop are provided. A new position of an anti-surge valve on the anti-surge loop is determined by correcting for dead time a value of the anti-surge parameter calculated from field measurements, based on a predicted anti-surge parameter estimated using a deterministic model which has as variables the field measurements and a current position of the anti-surge valve.

Abstract: A turbine includes a rotor and a casing that circumferentially surrounds at least a portion of the rotor. The rotor and the casing at least partially define a gas path through the turbine. A last stage of rotating blades is circumferentially arranged around the rotor and includes a downstream swept portion radially outward from the rotor. A method for reducing shock losses in a turbine includes removing a last stage of rotating blades circumferentially arranged around a rotor and replacing the last stage of rotating blades with rotating blades having a downstream swept portion radially outward from the rotor.