Abstract: A steam turbine 20 is provided with a casing 109, a turbine rotor 25 disposed through the casing 109, and labyrinth portions 50, 55 which are disposed at the boundary between the casing 109 and the turbine rotor 25. The steam turbine 20 is further provided with a sealing steam pipe 65 for supplying sealing steam to the labyrinth portions 50, 55 and a gas supply pipe 60 for supplying the labyrinth portions 50, 55 with a cooling gas for cooling the turbine rotor 25 or a heating gas for heating the turbine rotor 25.

Abstract: A turbine stage of a gas turbine engine is surrounded by a ring of liner segments. The liner segments can be moved radially in unison towards and away from the tips or fins of blades, by rotation of a connected unison ring, so as to avoid blade fin rub. Alternatively, the segments can be moved in a common direction by bodily movement of the connected unison ring so as to avoid blade fin rub during off axis rotation of the turbine stage.

Abstract: A control system for a rotary machine is provided. The rotary machine has at least one rotating member and at least one substantially stationary member positioned such that a clearance gap is defined between a portion of the rotating member and a portion of the substantially stationary member. The control system includes at least one clearance gap dimension measurement apparatus and at least one clearance gap adjustment assembly. The adjustment assembly is coupled in electronic data communication with the measurement apparatus. The control system is configured to process a clearance gap dimension signal and modulate the clearance gap dimension.

Abstract: A system for adjusting a clearance between blade tips of a turbine and a shroud assembly encircling the turbine in a turbine engine is disclosed herein. The system includes a first fluid passageway operable to extend from a first source of fluid at a variable pressure to a shroud assembly of a turbine engine. The first fluid passageway directs a first stream of fluid to the shroud assembly. The system also includes a first valve positioned along the first fluid passageway and moveable between open and closed configurations. The first valve is biased to the open configuration and moved to the closed configuration passively and directly by a first predetermined level of pressure of the first stream of fluid. During periods of relatively low power production of the turbine engine, the first valve is in the open configuration and moves to the closed configuration when power production of the turbine engine increases from relatively low power production.

Abstract: The invention relates to a compressor, which is axially flowed through, for a gas turbine having an axially displaceable rotor. An annular flow channel, which narrows in an axial direction, is formed between a rotationally fixed outer delimiting surface and an inner delimiting surface on the rotor. A stationary ring comprised of guide profiles and at least one ring comprised of moving profiles attached to the rotor are placed inside said annular flow channel. The end of each moving or guide blade is located opposite an axial section of one of both delimiting surfaces while forming a radial gap. The aim of the invention is to provide a non-positive-displacement machine having an axially displaceable rotor whose velocity losses are at least not increased during an axial displacement of the rotor.

Abstract: A fan system includes a rotatable axial flow fan unit, a fan shroud unit adjacent to the fan unit and capable of surrounding at least a portion of an outer periphery of the fan unit; and an actuator coupled to one of the units and operable to move said one of the units with respect to the other of the units, thereby varying immersion of the fan unit within the shroud unit. The actuator may be coupled to the shroud unit and is operable to move the shroud unit with respect to the fan unit. A control unit controls the actuator to vary fan immersion as a function of sensed parameter signals, and thereby maximizes fan efficiency.

Abstract: A control system for a rotary machine is provided. The rotary machine has at least one rotating member and at least one substantially stationary member positioned such that a clearance gap is defined between a portion of the rotating member and a portion of the substantially stationary member. The control system includes at least one clearance gap dimension measurement apparatus and at least one clearance gap adjustment assembly. The adjustment assembly is coupled in electronic data communication with the measurement apparatus. The control system is configured to process a clearance gap dimension signal and modulate the clearance gap dimension.

Abstract: An active clearance control system is provided that uses compressor extraction air to manipulate blade tip clearance in an industrial gas turbine and compressor. A stream of air is taken from a cooling and sealing air circuit and redirected to be used for active clearance control. The spent clearance control air is re-introduced into the hot gas path of the gas turbine for cooling and sealing purposes.

Abstract: A wind turbine with a sensor that measures the out-of-plane deflection of the blades and a controller that uses the signal from the sensor to determine the risk of a tower strike. The controller takes any necessary action to prevent a tower strike when it determines that the risk of a strike is high. The sensor can include strain gages or accelerometers mounted on the blades or it can include a fixed sensor mounted on the side of the tower to measure tower clearance as the blade passes by. The control action taken can include pitching blades, yawing the nacelle, or stopping the turbine. The controller is preferably a fuzzy logic controller.

Abstract: A gas turbine apparatus includes a compressor and/or a turbine, having rotor blades mounted on a rotor that is rotatable relative to a stationary housing, with a clearance gap between the rotor blades and the housing. During operation, external forces tend to deform the housing and the clearance gap. At least two actuators are arranged circumferentially offset from one another about the circumference of the housing. Each actuator is coupled to the housing and adapted to apply onto the housing a rotational moment about a torque axis that is at least approximately parallel to the housing axis. Based on the signal of a sensor that senses the deformation, a regulating unit actuates the actuators so as to counteract or compensate any deformations of the housing that arise during operation of the apparatus.

Abstract: Such a gas turbine is provided as can put into practical use a control technology which detects clearance between the tip of rotating blade and the inner circumference surface of ring segment surrounding them and adjusts the temperature, the pressure and the flow volume of the cooling fluid for blade rings/ring segments and the cooling fluid for rotors based on the output. A sensor is provided to detect the clearance between the tip of the rotating blade and the inner circumference surface of the ring segment. A sensor is integrated together with a first guide pipe by having a posterior portion thereof screwed together to a secondary pipe being installed to an edge of the first guide pipe inside of which a cooling fluid is introduced into. The first guide pipe is pressed to the blade ring from the outside of the casing so as to retain.

Abstract: A rotor system is provided whereby a rotary assembly such as a fan blade combination in a jet engine is brought into rub contact with a casing such that sensors detect vibration. The casing is then retreated in order to open the gap to a desired value for engine performance. In such circumstances, the rub contact position is defined as a base datum reference from which distance the casing is displaced in order to provide the specified gap for engine performance and efficiency.

Abstract: An apparatus for providing active clearance control between blade tips and seals in a turbomachine comprising: a first stator carrier segment, with stator seals centripetally disposed on it; a second stator carrier segment located along a same circumference as the first stator carrier segment, also with stator seals centripetally disposed on it; a shell that adjustably houses the first stator carrier segment and the second carrier segment; at least one displacement apparatus in operable communication with at least one stator carrier segment and configured to position the at least one stator carrier segment to provide active clearance control to the stator seals disposed on the at least one stator carrier segment.

Abstract: The invention relates to a method of a continuous determination of an instantaneous position of an impeller blade tip (5′) in a rotor turbine machine, particularly in a turbine impeller (6) in a turbojet engine during its operation in a real condition in order to obtain a current information on a technical state of the blade (5). In a selected place of an housing (7) of a rotor turbo machine, in a movement plane of impeller blade tips (5′), it is arranged in a stable manner at least one microwave antenna (3) with an aperture shape (4) which is consistent with an internal surface of an housing (7). The microwave signal (11), which is produced by a microwave homodyne system, is emitted, and then received, through a microwave antenna (3). The output signal (9) from that system, which carries out information on each instantaneous position of an impeller blade tip (5′) in relation to an antenna aperture (4), is converted by an electronic system, and then it is read.

Abstract: A wind power plant for producing electrical energy on a large scale, comprising a base, a housing, rotatable on said base around vertical axis. A wind tail, attached to the housing, rotate the housing toward direction of the wind, utilizing the power of the wind, and produces additional tunnel suction to the flow of the wind from front side to back side of the housing. A plurality of turbines, equipped with rotors with wide blades, is mounted inside the housing one above another. Deflectors cover from the wind the front side of the rotors above their axis of rotation while computer controlled governors are covering the remaining front side of the rotors below their axis of rotation, keeping steady the speed of rotation of the rotors. Working surfaces of turbines are covered from heavy snow and during the storm and protected from birds. Power plant saves the area of occupied land, utilizing higher speed of wind on higher elevations.

Abstract: A submerged motor vane wheel rotation direction control structure includes a blade pivoted to a locating block inside of the water guide chamber of a submerged motor, a vane wheel, the vane wheel having sloping teeth radially extended from the motor shaft of the submerged motor, which push the blade outwards toward to an open position for the passing of flow of water upon clockwise rotation of the vane wheel, and is forced into engagement with the blade to hold the blade in a close position upon counter-clockwise rotation of the vane wheel, causing the submerged motor to reverse the vane wheel.

Abstract: In a micro gas turbine engine, a capacitive sensor is used for measuring a tip clearance of a radial compressor section thereof, and an actuator is used for axially displacing a rotor shaft in response to an output from the capacitive sensor. Because the capacitive change gives an accurate measure of the size of the tip clearance, a particularly high sensitivity can be achieved in parts where the tip clearance is small, thereby providing a highly precise tip clearance control.

Abstract: In a micro gas turbine engine, a capacitive sensor is used for measuring a tip clearance of a radial compressor section thereof, and an actuator is used for axially displacing a rotor shaft in response to an output from the capacitive sensor. Because the capacitive change gives an accurate measure of the size of the tip clearance, a particularly high sensitivity can be achieved in parts where the tip clearance is small, thereby providing a highly precise tip clearance control.

Abstract: The broken shaft detection system and method uses a detector assembly mounted downstream of a power turbine wheel of a gas turbine engine to detect rearward axial motion of the wheel and thereby a broken shaft event. The detector assembly has a plunger positioned to be axially displaced against a link connected in an electrical circuit. The link may be broken when the plunger is displaced thereby creating an open circuit that may be detected by a detection and test element. The breaking may be communicated to an overspeed circuit that controls a shut off switch that interrupts fuel flow to the engine. The link may be connected to the detection and test element by two pairs of parallels wires to facilitate monitoring of circuit function and to detect failures that are not broken shaft event failures.

Abstract: Tip clearance apparatus for a gas turbine engine comprises a shroud ring having curved portions so as to allow eccentric offset and hence asymmetric movement of the shroud. The shroud ring is mounted within a guide also having corresponding curved portions and movement of the shroud ring is controlled by the use of sensors.

Abstract: The broken shaft detection system and method uses a detector assembly mounted downstream of a power turbine wheel of a gas turbine engine to detect rearward axial motion of the wheel and thereby a broken shaft event. The detector assembly has a plunger positioned to be axially displaced against a link connected in an electrical circuit. The link may be broken when the plunger is displaced thereby creating an open circuit that may be detected by a detection and test element. The breaking may be communicated to an overspeed circuit that controls a shut off switch that interrupts fuel flow to the engine. The link may be connected to the detection and test element by two pairs of parallels wires to facilitate monitoring of circuit function and to detect failures that are not broken shaft event failures.

Abstract: A stall precursor detector system for an axial flow compressor having at least one optical sensor to detect the deflection of a rotating airfoil of the compressor, means for comparing the deflection with a predetermined value, the predetermined value being indicative of onset of a stall in the compressor; and means for identifying onset of a stall and producing a stall onset signal if the deflection is greater than the predetermined value. A method for detecting a stall onset in an axial flow compressor system comprising (a) providing at least one optical sensor to measure the deflection of an airfoil, the deflection caused by a rotating stall cell; (b) comparing the deflection as measured in step (a) with a predetermined value indicative of a stall; and (c) identifying onset of a stall if the measured deflection is greater than the predetermined value.

Abstract: A stall precursor detector system for an axial flow compressor having at least one optical sensor to detect the deflection of a rotating airfoil of the compressor, means for comparing the deflection with a predetermined value, the predetermined value being indicative of onset of a stall in the compressor; and means for identifying onset of a stall and producing a stall onset signal if the deflection is greater than the predetermined value. A method for detecting a stall onset in an axial flow compressor system comprising (a) providing at least one optical sensor to measure the deflection of an airfoil, the deflection caused by a rotating stall cell; (b) comparing the deflection as measured in step (a) with a predetermined value indicative of a stall; and (c) identifying onset of a stall if the measured deflection is greater than the predetermined value.

Abstract: A centrifugal pump includes a casing having an outlet chamber and an impeller rotatable in the casing. A set of controlling sideplates are installed in the outlet chamber. The controlling sideplates are movable along the axis of the impeller, positioned such as to change the outlet width and the chamber volume thus allowing one to obtain the desired pumping parameters. A driving mechanism is connected to the sideplates, for their axial movement. The design contains driving mechanisms of the hydraulic type and electrical type. A pair of pilot shafts are connected to the sideplates and extend into a sensor for controlling the movement of the sideplates. A control system is also provided whose main purpose is adjusting the axial displacement of the sideplates, which automatically controls the variable pumping parameters.

Abstract: A method of actively controlling the clearance between the rotating components and the stationary components of a combustion gas turbine engine includes employing an active control system that controls the temperature of bleed air that is delivered to the stationary and rotating components to control the thermal growth thereof and to avoid a pinch point. The active control system includes one or more sensors and controls the operation of heat sources interposed within the air passages that deliver bleed air to the stationary and rotating components.

Abstract: A gas turbine engine (10) has a compressor (14) which includes a rotary stage (16) supported for rotation by a plurality of wire wound stators (34). When the stators (34) are electrically energised, they exert Maxwell type magnetic forces on a magnetically permeable ring (18) joining the tips of compressor blades (21) in the stage (16), and lift it into a position in space where it can rotate on a common axis with the turbine of the engine (10).

Abstract: A method and apparatus reduces the magnitude of vibratory strain in a turbomachine component that experiences high steady state strain by, in the case of a passive embodiment, coupling a mechanical-to-electromagnetic energy converter to an interior and/or exterior surface of the component, and/or embedding the energy converter within the component, and by, in the case of an active embodiment, coupling a mechanical-to-electromagnetic energy converter to an interior and/or exterior surface of the component.

Abstract: A system includes a gas turbine engine having a shroud and a rotor with one or more blades. The rotor rotates within the shroud to pressurize a fluid during operation of the engine. An electromagnetic actuator is also included that is operable to move the shroud relative to the rotor to adjust clearance between the shroud and blades. In addition, a controller is included in this system to determine a desired amount of clearance in accordance with an operating mode of the engine. The controller generates an actuation signal to change the clearance in correspondence with the desired amount. The electromagnetic actuator responds to the actuation signal to provide the desired amount of clearance.

Abstract: A clearance control system for a turbine seal optimizes a clearance by controlling the change in the clearance during a run due to a thermal elongation by cooling the sealing air. The air from a compressor is cooled by a cooler 12 and is guided via an outer shroud 22 and a tube 28 in a stationary blade 21 into a cavity 26 in an inner shroud 23. The air flows through a space 34 from a seal portion 36 to the outside and through a seal ring 25 and a space 35 from a seal portion 37 to the outside to seal the inner side of the inner shroud 23 from a hot combustion gas. A clearance .delta.H between a stationary portion and a rotary portion changes due to a thermal elongation. A clearance measuring sensor 14 monitors the clearance .delta.H without intermission. When the clearance .delta.H is large, the control unit 10 opens the flow regulator valve 11 to cause the air to bypass the cooler 12. When the clearance .delta.

Abstract: An upper reservoir-side conduit or a lower reservoir-side conduit is branched in the vicinity of pump-turbine ends and at least a first pump-turbine out of a plurality of pump-turbines which share the conduit portions located farther than the branch points with the other pump-turbine or pump-turbines is provided with a rotational speed increase detector. When it is detected that the rotational speed of the first pump-turbine has exceeded a second predetermined value higher than a rated speed, a command is issued also to at least one of the other pump-turbines to limit the guide vane closing speed in that pump-turbine to a speed approximately equal to or lower than the speed after the shift to a slow closing of the guide vanes.

Abstract: A compressor is disclosed having a characteristic modifier, such as air injection, adapted to modify an operating characteristic of the compressor in order to reduce the bandwidth and rate limit requirements of the compressor. The compressor includes an actuator, such as a bleed valve, whose bandwidth and rate limit parameters meet the corresponding reduced requirements of the compressor. The actuator is adapted to stabilize the compressor with respect to a likely condition in the compressor which would tend to make the compressor operate in a less stable manner. This makes it possible to stabilize the compressor using a more readily available actuator having lower bandwidth and rate limit parameters.

Abstract: A machine having protruding elements 26 and an adjacent abradable seal 18, which move relative to each other, an air-path clearance G between the seal 18 and the elements 26 and an element distance D2 between the sensor 10 and the elements 26, is provided with a sensor 10 which is recessed within the seal 18 by a recess distance D. A clearance/thickness circuit 14 provides transmitted and reflected microwave signals 30,32 along a coaxial cable 12 having a characteristic impedance, to the sensor 10, which has an impedance substantially matched to the characteristic impedance of the cable 12. The sensor 10 provides the reflected signal 32 which is indicative of the recess distance D when the elements 26 are not in front of the sensor 10 and is indicative of the blade distance D2 between the sensor 10 and the elements 26 when the elements 26 are in front of the sensor 10.

Abstract: The blades and the outer case of an encased engine, such as a turbo engine or the like will expand and contract during periods of operation. Blade expansion and contraction can result from operating temperature changes, rotational velocity changes, or the like. The engine casing includes a segmented seal which is properly spaced apart from the engine blade tips so as to provide optimum operation of the engine. Proximity sensors mounted on the engine detect the radial clearance of the engine blades to the seal segments at all times. The seal segments are mounted on a corrugated piezoelectric support which is electrically stimulated so as to properly adjust the seal segments relative to the blade tips to provide the proper spacing as the blades and case expand and contract. Appropriate stimulation of the piezoelectric support will move the seal segments toward or away from the blade tips as needed.

Abstract: An electro optic sensor for sensing unwanted axial motion of the turbine of a gas turbine engine away from its normal position, includes a pair of fiber optic wave guides interconnected through a frangible member disposed axially adjacent the turbine rotor. Upon axial movement of the rotor away from its normal position, the frangible element is broken to open the optical circuit associated with the guides. Associated electronic circuitry generates an output signal indicative of failure of the gas turbine rotor.

Abstract: A turbo compressor in which a rotor having impellers is supported by a magnetic bearing is constructed such that a control valve is provided in a thrust balancing line connecting a suction line of the compressor to a balancing chamber formed outside a balancing drum provided at one end side of a rotor. The control valve serves to regulate a rate at which a gas flows through the thrust balancing line, and is adapted to be controlled in relation to a load imposed upon the magnetic thrust bearing.

Abstract: A turbomachine including a case, a rotor, a plurality of rotor blades on the rotor each having a blade tip, a shroud around the rotor blade tips, and bearings mounting the rotor on the case for rotation about a centerline of the case and for bodily shiftable movement in the direction of the centerline. The rotor blade tips and an inside wall of the shroud flare radially outward in the direction of the centerline so that when the rotor moves in the direction of the centerline toward the shroud a clearance gap between the blade tips and the inner wall of the shroud decreases and vice versa. An electromagnetic actuator on the case magnetically attracts a thrust plate on the rotor against a net dynamic force on the rotor. A control system of the actuator controls the magnetic attraction of the actuator in response to signals from a position sensor measuring the actual magnitude of the clearance gap to maintain the actual clearance gap at a predetermined magnitude.

Abstract: In conjunction with a method and apparatus for regulating the power of a steam power plant block, an improved method and an improved apparatus for restoration of a given throttling of the turbine inlet valves as a conclusion to a regulating process for stabilizing a sudden or abrupt elevation of the load set point is proposed by the invention. The necessary storage of fresh steam takes place without influencing the electrical output power or the regulating devices necessary for regulating it with the aid of a separate closed control circuit.

Abstract: A positioning system for a steam turbine element includes a plurality of flex plates which support an inner cylinder of a steam turbine element with the rotating blades of a rotor and the stationary blades of the inner cylinder at a predetermined position. Sensors detect shifting of the rotor within the inner cylinder and provide control signals to a motor which drives the inner cylinder in an axial direction to account for shifting of the rotor.

Abstract: A control system 30 for measuring the clearance "x" between the tip 26 of a blade 24 and wall 28 in a turbine engine8. A series of probes 32, 32' and 32.sup.N located in the wall 28 each have a reference orifice 52 and a sensing orifice 54. Fluid from a source flows through the reference orifices 52 into the turbine engine. This fluid flow is substantially unrestricted and as a result a fluid pressure P.sub.2 is established in a reference chamber 44. Fluid flow from the sensing orifice 54 is restricted by the relationship of the tip 26 of each blade 24 and as a result fluid pressure P.sub.2 ' is created in chamber 48. A multiplexer 62 sequentially provides transducer 92 and 94 with fluid pressure P.sub.2 from the reference chamber 44 and P.sub.2 ' from sensing chamber 48. The transducers 92 and 94 convert the pneumatic signals into electrical signals which are supplied to a computer 116.

Abstract: The invention relates to a type of proximity sensor. In one form, two sinusoidal signals travel along two transmission lines near an object. When the distance between one or both of the lines and the object changes, the speed of travel of one or both of the signals changes. There is a correlation between the speed change and the distance, thus allowing one to infer distance from speed change. One way to measure the speed change is to measure the phase relationship between the two signals. The invention can be used to measure clearances between turbine blades and turbine shrouds in gas turbine aircraft engines. Based on the measured clearance, other apparatus can direct hot or cold air upon the shroud to expand or shrink the shroud, thereby changing the clearance.

Abstract: A leakless pump for sucking and delivering a liquid includes a rotor having an impeller thereon and rotatably journaled by bearings, and a casing surrounding the rotor and the impeller. The pump comprises a bypath for flowing part of the liquid from a high pressure portion in the proximity of an outer circumference of the impeller to a low pressure portion on a side of an inlet of the pump, at least one pressure detecting aperture formed in the casing and having an inner end communicating with the bypath for measuring change in pressure in the bypath due to wear of at least one of the bearings, and pressure detecting means provided at an outer end of the pressure detecting aperture for detecting pressure change in the bypath, thereby detecting the change in pressure to detect wear of the bearings.

Abstract: A microwave probe has a cylindrical support made of stabilized zirconia being excellent in heat insulation, and the cylindrical support is threadably installed at a partitioning wall to partition an atmosphere of high temperature. The support is provided at the center with a through hole, and an antenna for transmitting or receiving microwave is installed at one opening of the through hole positioning at outside of the partitioning wall, and a metal ring member is installed at other opening of the through hole positioning within the partitioning wall. The transmitting and receiving antenna and the ring member are fixed to respective openings by a ceramic adhesive which is filled in the through hole and excellent in heat insulation. A part of the ring member projects in the atmosphere.

Abstract: In a turbine engine (8) having a shaft (60) with turbine blades (24, 24', . . . 24.sup.N) thereon which rotate in a chamber (12) of the engine housing (10) to produce thrust in response to an operator input. A pneumatic sensor system (30) connected to said housing (10) for maintaining the space relationship between the tip (26, 26', . . . 26.sup.N) of the blades (24, 24', . . . 24.sup.N) and the wall (28) of housing 10 within set limits under varying operational conditions experienced by the turbine engine (8).

Abstract: A fail-safe system is used in a control unit for opening and closing guide vanes of a pump-turbine apparatus operable in both of pump operation mode and turbine operation mode. The fail-safe system has a wire carried by a rotatable sheave adapted for transmitting an information concerning an opening degree of the guide vanes, a weight suspended from one end of the wire, an operation rod disposed below and in alignment with the weight in the direction of action of the force of gravity, and a change-over valve adapted to be switched by the operation rod. When the wire is cut off accidentally, the weight drops onto the operation rod to depress the latter to switch the change-over valve so that a servo-motor is switched to make the guide vanes close at predetermined rates of change of the opening degree in respective operation modes.

Abstract: A rotor for a gas turbine engine includes a turbine wheel with a centerbore therethrough, a main shaft projecting through the centerbore, a turbular stub shaft surrounding the main shaft at a turbine end of the latter and being rigidly connected thereto so that the stub shaft defines a radially spaced reverse flange on the main shaft, a tubular reference shaft around the main shaft having an output end rigidly connected to an output end of the main shaft and a turbine end rotatably journaled on an inside surface of the stub shaft, a plurality of axial slots in the stub shaft, a plurality of pole supports projecting radially from the reference shaft turbine end through the stub shaft slots, a plurality of first pole pieces on the pole supports, a plurality of second pole pieces on the stub shaft between the first pole pieces, and a stationary pick-up operative to develop an electrical signal proportional to the spacing between the pole pieces while the rotor rotates which spacing is proportional to rotor torqu

Abstract: An apparatus and method is provided for initializing and calibrating a microprocessor controlled refrigeration system including a centrifugal compressor having a variable width diffuser section.

Abstract: An assembly is disclosed for automatically balancing thrust on the rotor of a gas turbine engine. An annular chamber axially positioned relative to the rotor is adapted to receive pressurized hydraulic fluid and apply it to the rotor. The force thereby applied to the rotor is regulated by sensing changes in axial rotor thrust and delivering hydraulic fluid to the chamber at a pressure sufficient to balance axial forces acting on the rotor.

Abstract: A method and apparatus for controlling a multistage hydraulic machine in which respective pressure stages are connected in series through runners and return passages and the highest and lowest pressure stages are provided with movable guide vanes, are organized such that the guide vanes of either one of the two pressure stages are controlled in accordance with the load of the hydraulic machine, while the guide vanes of the other one of the two pressure stages are controlled in accordance with a relation defined by the load of the lowest pressure stage and the load of the hydraulic machine.

Abstract: A turbo-molecular pump has passive magnetic bearings which are radially stable but axially unstable and mechanical thrust bearings acting axially, the magnetic bearings and the stator forming a structural unit movable axially within the pump housing and connected to an element adjustably supporting one thrust bearing while the other thrust bearing is fixed to the housing with control gear being provided for adjusting the structural unit relative to the housing and the thrust bearing relative to the structural unit in dependence on force sensing devices.

Abstract: A casing support structure for a gas turbine engine is provided with means for reducing the effect of distortions such as are produced by differential heating of the structure on shut-down. To this end the casing is mounted from supporting structure by links which are arranged to be individually heated by associated heaters. The degree of heating of the links is arranged to provide differential expansion which moves the casing so as to reduce the effect of eccentricities on the clearance between the casing and its associated rotor structure.