Abstract: The present invention relates to a blade for a gas turbine, in particular of an aircraft engine, having a blade airfoil, which has a blade-root-side first profile section and a blade-tip-side second profile section, which is spaced apart from the first profile section in a radial direction, from the first profile section to the second profile section, by a blade airfoil height, wherein a stagger angle of the blade airfoil changes with a height in the radial direction over the first profile section at least over certain portions, wherein, in a first region between a first height and a second, greater height, the change in the stagger angle over the height does not decrease with increasing height at least over certain portions.

Abstract: Rotor blade for a wind power installation, rotor for a wind power installation, and wind power installation. The disclosure relates in particular to a rotor blade for a wind power installation, having a rotor blade length, having a profile depth established between a leading edge and a trailing edge, and having a profile thickness established between a suction side and a pressure side, wherein the rotor blade has a trailing edge region, which adjoins the trailing edge and extends with a region extent of less than 20%, in particular less than 10%, of the profile depth in the direction of the leading edge, wherein the trailing edge region has at least one acoustic opening.

Abstract: Turbomachines having one or more flow guiding features designed to increase the performance of the turbomachine. In some examples, flow guiding features are designed and configured to bias a circumferential pressure distribution at a diffuser inlet toward circumferential uniformity, otherwise account for such low-frequency spatial pressure variations, increase the controllability of spatial flow field variations, or modifying flow field variations, etc. In some examples, a diffuser having a row of vanes that include a plurality of first vanes and at least one second vane having a different characteristic than the first vanes are disclosed. In some examples, diffusers have an aperiodic section including one or more biased passages for biasing a flow field. And in some examples, turbomachines have flowwise elongate recesses in one or both of a hub and shroud surface.

Abstract: Various embodiments are provided herein for a system and method for air compression. In at least some embodiments provided herein, there is provided a compressor device having an annular chamber, at least one inlet port, at least one blade, at least one dynamic partition wall and at least one outlet, wherein when the at least one partition wall is in a closed position, the at least one blade approaching the at least one partition wall causes the air to compress and wherein when the at least one partition wall is in the open position, at least one blade moves from a first side to a second side of the at least one partition wall. The compressor device may contain a gearbox train configured to move the at least one partition wall from the closed position to the open position when the at least one blade is within a predetermined distance.

Abstract: An aircraft propeller, including a propeller shaft and propeller blades or propeller airfoils secured on the propeller shaft, wherein an inlet-side flow channel and an outlet-side flow channel are introduced into each of the propeller blades or each of the propeller airfoils, wherein each inlet-side flow channel has an inlet opening and each outlet-side flow channel has an outlet opening on each of the propeller blades or propeller airfoils, wherein each inlet-side flow channel has a connection to the outlet-side flow channel of a respective other propeller blade or propeller airfoil such that air flowing in via the inlet-side flow channel flows out via the outlet-side flow channel of the respective other propeller blade or propeller airfoil, and wherein the inlet opening and the outlet opening of each propeller blade or propeller airfoil are arranged on different sides of the propeller blade or propeller airfoil.

Abstract: A combustor includes an inner liner forming a combustion chamber; an outer liner surrounding the inner liner to form a cooling passage in which compressed air flows; and a plurality of cooling guides installed around an inner circumferential surface of the outer liner to surround the combustion chamber, each of the cooling guides protruding from the inner circumferential surface to create an impinging jet from the compressed air flowing in the cooling passage. The plurality of cooling guides surrounding the combustion chamber are installed at regular intervals in a flow direction of the compressed air, and are arranged in staggered axial rows. Each cooling guide includes an air guiding surface facing the flow of the compressed air to guide the compressed air toward the inner liner. Accordingly, liner cooling efficiency can be enhanced by more effectively guiding the impinging jet toward the inner liner.

Abstract: The present invention involves a method for manufacturing a blade (1) for a propeller, which blade (1) has a leading edge (2) and a trailing edge, the method comprising the steps of: forming a conduit in the blade (1), making a plurality of holes (7) through which the conduit (6) communicates with the exterior of the blade (1), and providing a blade blank having an edge part receiving surface (4) extending along at least a major part of the leading edge (2) of the blade (1) to be manufactured, wherein forming a conduit (6) comprises building up an edge part (3) onto the edge part receiving surface (4) by a wire-based additive manufacturing process, wherein the additive manufacturing process is adapted to form the conduit (6) at least partly delimited by the edge part (3) and extending along the leading edge (2) of the blade (1) to be manufactured.

Abstract: The present disclosure relates to a wind power installation having an aerodynamic rotor with at least one rotor blade, wherein the rotor blade has an active flow control device, which is designed to actively influence a flow over the rotor blade, wherein the flow control device comprises an opening in a rotor blade surface, referred to as a rotor blade surface opening, wherein the flow control device is configured to draw off and/or blow out air through the rotor blade surface opening air by way of a controllable air flow, wherein the wind power installation has a controller which is configured to control an amount of the controllable air flow through the rotor blade surface opening according to at least one of the following rules: if a rotational speed threshold value of a rotational speed of the rotor is exceeded, increasing the maximum controllable air flow successively with increasing rotational speed, if a torque threshold value of a torque of the rotor is exceeded, increasing the maximum controllable ai

Abstract: An exhaust diffuser hub disposed at a longitudinal center of an exhaust diffuser is provided. The exhaust diffuser hub includes a hub extension extending from a downstream end thereof in a longitudinal direction of the exhaust diffuser. A transverse cross-sectional area of the hub extension is smaller than a transverse cross-sectional area of the hub.

Abstract: A combination of an airfoil, turbine blade, or compressor blade with a flow separation control device includes an airfoil and a flow separation control device. The airfoil includes a body with an upper surface and a lower surface that extend from a leading edge to a trailing edge. The flow separation control device includes a plurality of openings on the upper surface of the body.

Abstract: A gas turbine engine including a compressor section, a combustor section fluidly connected to the compressor section, a turbine section fluidly connected to the combustor section, and a plurality of gas path components exposed to a primary fluid flowpath through the compressor section, the combustor section and the turbine section. At least one of the gas path components includes an exterior facing surface, a lattice structure extending outward from the exterior facing surface, the lattice structure being integral to the exterior facing surface, and a thermal barrier coating adhered to at least a portion of the exterior facing surface and the lattice structure.

Abstract: A system for locating airflow modifiers for installation on wind turbine rotor blades may generally include a plurality of airflow modifiers, with each airflow modifier including a base defining an outer profile that differs from the outer profiles of the remainder of the airflow modifiers. The system may also include a blade shell defining an exterior surface. The base of each airflow modifier may be configured to be coupled to the exterior surface of the blade shell. In addition, the system may include an installation template provided on the exterior surface of the blade shell. The installation template may define a different installation location for each of the airflow modifiers. Moreover, the installation template may include a geometric feature at each installation location that at least partially matches the outer profile of the airflow modifier configured to be installed at such installation location.

Abstract: The invention proposes a method for producing a protective reinforcement for the leading edge (BA) or trailing edge of a blade (P), the leading edge (BA) or trailing edge being curved, the method comprising steps of flattening (102) a hollow tube (1) so as to form at least one fold line (6) extending along the tube (1), opening (104) the flattened tube (1) by cutting the tube (1) along a cutting line (8) opposite the fold line (6) with respect to the tube (1), so as to form two flanks (16, 18) linked at the fold line (6) and intended to be mounted on the pressure side and the suction side of the blade (P), the method being characterised by a preliminary step (100) of bending the hollow tube (1) carried out before the flattening (102) and adapted such that the fold line (6) after flattening (102) is curved and substantially matches the curved leading edge (BA) of the blade (P).

Abstract: The present invention relates to a turbine assembly having an aerofoil and/or an end wall each having an outer surface with a structure for directing a flow of a cooling medium at the outer surface. The structure at the outer surface has at least a first groove and a second groove extending in the outer surface from a leading to a trailing edge and being oriented in at least two different directions with a deflection angle (?) towards each other, with the deflection angle (?) having a component in a span wise direction of the aerofoil. The structure at the outer surface of the end wall has at least a first groove and a second groove extending in an axial direction of the turbine assembly, matching an outer profile of the aerofoil and oriented in at least two different directions with a deflection angle (?) towards each other.

Abstract: A scroll screen centrifugal separator includes a distributor that is configured to receive slurry received from a feed conduit. The distributor is configured to deflect the received slurry to a screen of the scroll screen centrifugal separator. In some embodiments, the distributor may include a distributor that has a flat surface encircled by a lip or having one or more lips positioned on the flat surface, an inclined surface, or a declined surface that faces the mouth of the feed conduit. In other embodiments, the distributor may include a plurality of dam members for defining passageways through which slurry is passable through the distributor prior to being ejected to a screen of the separator. In other embodiments, the distributor may include a distributor plate that has a plurality of radial arms attached thereto that are configured to direct slurry to the basket with a rotational velocity.

Abstract: A device comprising a vertical axis wind turbine comprising an arm, a housing coupled to the arm, a generator housed within the housing, and a blade extending along the housing vertically.

Abstract: A rotor system is disclosed for a reactive drive rotary wing aircraft. Apparatus and methods are disclosed for maintaining the rigidity of the rotor and eliminating play between flight controls and the rotor by mounting swashplate actuators to a flange rigidly secured to the mast. Apparatus and methods are disclosed for thermal management of the rotor in order to avoid bearing failure or loss of bearing preload. Methods include modulating the temperature of oil pumped over one or more of the mast bearing, swashplate bearing, and spindle bearing. The temperature of air passively or actively drawn through rotor may also be modulated to maintain bearing temperature within a predetermined range. Structures for reducing pressure losses and drag on components due to air flow through the rotor are also disclosed. A rotor facilitating thermal management by oil and air flow is also disclosed.

Abstract: A diffuser of a compressor of centrifugal or mixed type includes two end plates which enclose a plurality of regularly distributed circumferential blades, and at least one transverse upstream passage produced in lower or upper surfaces of the blades. An injection/withdrawal coupling is achieved by a recirculation of a stream in an air passage of the diffuser on the basis of injection of air from at least one point in a leading edge zone of an upstream side of the diffuser. Blowing of air is then effected in at least one groove formed along a lateral flank of each blade by withdrawal of the air stream in a region of a trailing edge. Thereby, effectively separation of the air in a boundary layer in a gas turbine compressor diffuser is realized by re-energizing the boundary layer with air at a higher pressure by a suction/re-injection coupling.

Abstract: An airfoil active bleed system and related method. A housing includes an induction wall, an exhaust wall having one or more exhaust ports, and a chamber between the induction and exhaust walls. Zero-net-mass-flux actuators are located in the chamber and configured and positioned to collectively induct fluid through the induction wall and selectively exhaust fluid through the exhaust port(s).

Abstract: A prediction of whether a point on a computer-generated surface is adjacent to laminar or turbulent flow is made using a transition prediction technique. A plurality of instability modes are obtained, each defined by one or more mode parameters. A vector of regressor weights is obtained for the known instability growth rates in a training dataset. For an instability mode in the plurality of instability modes, a covariance vector is determined. A predicted local instability growth rate at the point is determined using the covariance vector and the vector of regressor weights. Based on the predicted local instability growth rate, an n-factor envelope at the point is determined.

Abstract: A casing treatment 4 including a recirculation passage 41 and a mixing piping 6 are provided. The recirculation passage 41 has a first recirculation opening 42 and a second recirculation opening 43 that are in communication with each other, the first recirculation opening 42 being formed inside a compressor housing 11 of an exhaust gas turbocharger and opening to an air passage 15 upstream of a compressor impeller 3, the second recirculation opening 43 being formed at the outer circumferential section of the compressor impeller 3. The mixing pipe 6 opens to the recirculation passage 41 and has a return opening 14 for introducing EGR gas and blow-by gas to the recirculation passage 41.

Abstract: A fan nacelle for a gas turbine engine includes a leading edge region with a flow path between an intake region in a nacelle outer surface and an exhaust region in a nacelle inner surface to locally modify a flow around the leading edge region during a predefined off-design condition.

Abstract: A turbomachine compressor including variable-pitch vanes including an aerofoil section connected by a mounting plate of circular outline to a pivot guided in rotation in an orifice in a casing is disclosed. The mounting plate of the vane includes at least one notch for bleeding air from the compressor stream. The notch is intended to communicate with a hole in the casing in order to remove the air bled off when the vanes are in a first position, and to be closed off by this casing when the vanes are in a second position, so that the flow rate of bled air depends on the pitch angle of the vanes.

Abstract: A tip turbine engine according to the present invention includes a plurality of independently variable inlet guide vanes for the fan and/or for the compressor. An actuator is operatively coupled to each of the flaps, such that each actuator can selectively vary the flap of its associated inlet guide vane. In one embodiment, the inlet guide vanes each include a pivotably mounted flap that is variable independently of the flaps of at least some of the other inlet guide vanes. In another embodiment, the inlet guide vanes each include at least one fluid outlet or nozzle directing pressurized air, as controlled by the associated actuator, to control inlet distortion.

Abstract: A boundary layer energizer (20) for energizing a boundary layer flow over a surface (22), the boundary layer energizer (20) comprising a plurality of passages (24), each passage terminating in a respective hole (26) provided on the surface (22), the holes being arranged in a cluster (23) on the surface, wherein the plurality of passages are angled with respect to one another at the surface such that, when in use, a vortex (24) is formed by a fluid flowing through the plurality of passages.

Abstract: A hydroelectric generator includes a body and an electromechanical apparatus cabin. The body has a tube penetrating the body and a first flow channel. The tube has a tapering segment and a throat portion communicating with the first tapering segment. One end portion of the first flow channel is located on a wall surface of the throat portion, so that the first flow channel communicates with the tube. The first flow channel is used to enable a fluid to flow into the tube from the first flow channel or guide a fluid to flow out of the body from the throat portion. The electromechanical apparatus cabin has an energy retrieving apparatus disposed in the throat portion of the tube, and the end portion of the first flow channel communicating with the tube is located at a front side or a back side of the energy retrieving apparatus.

Abstract: A shroud for a turbine and a method of assembling is provided. The turbine includes a housing, a rotatable shaft and a bucket extending outward therefrom. The shroud includes an alignment member which is coupled to the housing, wherein the alignment member includes a first end, a second end and a body extending between the first and second ends. The second end includes an arcuate portion to facilitate fluid flow downstream from the bucket. The shroud further includes a seal coupled to the body to facilitate sealing a gap defined between the bucket and the body.

Abstract: A partial pitch wind turbine is described wherein the wind turbine blade has an inner blade section designed for stall-controlled operation and an outer blade section designed for pitch-controlled operation. The different blade profiles for the different sections allow for the efficient operation of the blade while providing for the control of the wind turbine to effectively reduce blade root moments. The outer blade sections can be pitched out of the wind to reduce root moments due to the outer blade sections, while the increasing power capture of the inner blade section maintains nominal power output.

Abstract: A circulation structure for a turbo compressor, in particular for a compressor of a gas turbine, is disclosed. The circulation structure includes at least one annular chamber that can be traversed in a circumferential direction, is concentric with a shaft of the turbo compressor in the region of the free blade ends of a blade ring, and radially borders a main flow channel. Several chambers that can be traversed in an axial direction are situated upstream of the or each annular chamber, when viewed from the main flow direction of the main flow channel.

Abstract: A compressor of an exhaust gas turbocharger has a compressor housing of a divided type that forms an inlet slit, an outlet slit and a recirculation passage at the same time when the compressor housing is assembled. In the compressor of the exhaust gas turbocharger, mating surfaces of compressor housing members 9a and 9b are formed in the neighborhood of the inlet part of the impeller 5 in the compressor housing 9 that is divided into the compressor housing members 9a and 9b in the direction of the rotation axis of the impeller; and, a space forming the recirculation passage 29, an inlet slit 25 and an outlet slit 27 are formed between the mating compressor housing members 9a and 9b.

Abstract: The invention relates to a compressor for a turbine engine including a casing (4), at least one compressor stage consisting of a stationary blade (2) impeller and a mobile blade (1) impeller positioned upstream from said stationary blade (2) impeller, and cavities (5) made in said casing opposite the through-path of the mobile blades (1), said cavities having a length L2 measured axially and being shifted upstream relative to the blades (1) so as to generate an overlap with a length L1, characterized in that the lengths L1 and L2 are respectively between 35% and 50% and between 80% and 90% of the axial chord Cax measured at the outer end of the blades (1), and in that the cavities (5) do not in communication with one another.

Abstract: A compressor typically for use in a turbocharger comprises a downstream radial compressor impeller wheel, an upstream axial compressor impeller wheel and an intermediate stator. The compressor housing has an inlet with inner and outer walls that define between them an MWE gas flow passage. An upstream opening defined by the flow passage provides communication between the passage and the intake and at least one first slot downstream of the upstream opening provides communication between the passage and the inner surface of the inner wall. The stator comprises a plurality of fixed vanes and is disposed in the inner wall of the inlet between the radial and axial impeller wheels. The position of the slot can be at one of several positions along the gas flow passage, in other embodiments there are second and third slots and the flow passage is divided into two parts. All the arrangements are designed to improve the compressor map width.

Abstract: An apparatus (10) is presented for controlling a boundary layer (30) in a diffusing flow path (14) of a power generating machine (16). The apparatus includes a passage (18) in the power generating machine with an inlet (20) and an outlet (22). The apparatus also includes a fluid source (24) coupled to the inlet to transmit fluid into the passage. The apparatus also includes a vortex generator (26) within the passage effective to generate a vortex fluid (12) at the outlet. The outlet is positioned to inject the vortex fluid into the diffusing flow path of the power generating machine in order to control the boundary layer of the diffusing flow path. An apparatus is also provided to enhance the diffusion of a flow path within a power generating machine.

Abstract: A rotor blade for a gas turbine engine, comprising an aerofoil having pressure and suction surfaces, leading and trailing edges, and an array of passages at a tip region of the aerofoil. The passages extend from the pressure surface to the suction surface of the aerofoil and are disposed so that the array creates, in operation, a planar jet of gas issuing from the suction surface. The jet is inclined outwardly from the suction surface and towards the tip, and in the direction from the leading edge to the trailing edge. The jet inhibits migration away from the suction surface of a clearance vortex formed by leakage of air over the tip of the rotor blade.

Abstract: A gas turbine is disclosed which includes an annular combustion chamber defined by an inner wall and an outer wall. A stator airfoil row can be defined by an annular inner stator wall and an annular outer stator wall housing a plurality of stator airfoils, and at least a rotor airfoil row defined by an annular inner rotor wall and an annular outer rotor wall housing a plurality of rotor airfoils. A gap is arranged, for example, between at least one of the inner stator wall and the inner combustion chamber wall, and the outer stator wall and the outer combustion chamber wall, upstream of said stator airfoil row. A border of at least one of the inner and outer stator wall facing the gap can be axisymmetric.

Abstract: An arrangement with a ring diffuser for an axial turbomachine, for example for a gas turbine, is provided. The ring diffuser includes an outer wall and with an inner wall coaxial thereto, between which a diffuser duct extends in ring form along an axial extent so as to diverge from an inflow-side end to an outflow-side end, the inner wall and the outer wall in each case including a wall surface delimiting the diffuser duct. In order to specify a diffuser duct which is adapted to an inflow uneven along the circumference and by means of which a specially efficient conversion of kinetic energy into static energy is possible, the wall surface which delimits the diffuser duct on the inlet side is rotationally asymmetrical.

Abstract: A ring diffuser for an axial turbomachine is provided. The ring diffuser includes an outer wall and an inner wall coaxial thereto, between which a diffuser channel extends in a ring shape along an axial extension from an inflow-side end diverging to an outflow-side end, wherein the inner wall and the outer wall each include a wall surface bounding the diffuser channel. In order to specify a diffuser channel that is tailored to an inflow that is uneven along the circumference and that facilitates a particularly efficient conversion of kinetic energy into static energy, a rotationally asymmetric wall surface bounding the diffuser channel on the inlet side is provided.

Abstract: The present application provides an axial flow turbine. The axial flow turbine may include a stator casing and a turbine bucket positioned about the stator casing. A tip shroud may be positioned on the turbine bucket. A shroud tail may be attached to the tip shroud at a downstream end of the tip shroud.

Abstract: The disclosure relates to a radially fed axial steam turbine with a cold inlet duct, axially displaced from a hot inlet duct such that is it further away from a first blade row than the hot inlet duct. The cold inlet duct receives a cold steam from a cold inlet spiral and directs it into the hot inlet duct in such a way that a boundary layer of cold steam is formed over the rotor circumferential surface between the outlet end of the cold inlet duct and the blade and vane rows. The rotor circumferential surface is also adapted to promote and maintain the boundary layer. In this way, a maximum temperature to which the rotor is exposed can be reduced.

Abstract: A compressor typically for use in a turbocharger comprises a downstream radial compressor impeller wheel, an upstream axial compressor impeller wheel and an intermediate stator. The compressor housing has an inlet with inner and outer walls that define between them an MWE gas flow passage. An upstream opening defined by the flow passage provides communication between the passage and the intake and at least one first slot downstream of the upstream opening provides communication between the passage and the inner surface of the inner wall. The stator comprises a plurality of fixed vanes and is disposed in the inner wall of the inlet between the radial and axial impeller wheels. The position of the slot can be at one of several positions along the gas flow passage, hi other embodiments there are second and third slots and the flow passage is divided into two parts. All the arrangements are designed to improve the compressor map width.

Abstract: An exhaust diffuser system and method for a turbine engine. The outer boundary may include a region in which the outer boundary extends radially inwardly toward the hub structure and may direct at least a portion of an exhaust flow in the diffuser toward the hub structure. At least one gas jet is provided including a jet exit located on the outer boundary. The jet exit may discharge a flow of gas downstream substantially parallel to an inner surface of the outer boundary to direct a portion of the exhaust flow in the diffuser toward the outer boundary to effect a radially outward flow of at least a portion of the exhaust gas flow toward the outer boundary to balance an aerodynamic load between the outer and inner boundaries.

Abstract: The disclosed embodiments relate to turbulence inducing mechanisms applied to portions of wind turbine blades and methods for increased power production using turbulence inducing mechanisms. Embodiments provide methods and mechanisms for increasing the range of optimal wind performance for wind turbines and provide for increasing the maximum energy producing capacity of wind turbines at a given wind speed. Some embodiments have a rotor blade that includes a capture side and a drag side. The blade also includes a film disposed over at least a portion of only the drag side of the blade. The film comprises a conformable sheet material with a plurality of perforations therethrough which are configured to induce turbulence on a fluid flowing thereover. The turbulence inducing film reduces the drag of the blade and consequently increases the blade's rotational speed at a given wind speed, which increases the turbine's power production and optimal performance range.

Abstract: A gas turbine engine is provided with a nacelle having a hollow inner space. The inner space is utilized as a plenum for directing air from an inlet to an outlet at the upstream end of the nacelle to allow control of an effective lip width of the nacelle under certain flight conditions.

Abstract: A compressor section includes a rotor platform; a rotor blade extending radially outwardly from the rotor platform, the rotor blade including a pressure sidewall and a circumferentially opposing suction sidewall extending in a radial direction between a root and a tip and in an axial direction between a leading edge and a trailing edge; a casing having an inner surface surrounding the tip and spaced radially outwardly thereform to define a gap therebetween; a plurality of grooves disposed in the inner surface of the casing and extending in a generally circumferential direction, the plurality of grooves including a first groove and a second groove; and a channel system comprising at least a first channel positioned within the casing and configured to provide fluid communication between the first groove and the second groove.

Abstract: Axial-flow compressor including, within a compressor casing (4), at least one rotor (2) of rotor blades (3) connected to a drive shaft (1) and a stator (5) held on the casing inner wall and, associated to the rotor gap (6) between the blade tips and the casing inner wall, a flow pulse generator (7) for stabilizing the rotor gap flow, characterized in that the flow pulse generator (7) includes pulse channels (7a) arranged on the inner wall of the casing and extending upstream of the rotor (2) and tapering in flow direction to accelerate the wall-near flow (9), with the shape and size of the pulse channels (7a) being determined by circumferentially spacedly disposed, successive separators (7b) attached without gap on the compressor casing inner wall. The flow pulse generator (7) so designed, which is easily manufacturable, improves the stabilization of the rotor gap (6) flow, extends the operating range of the compressor and increases the surge limit.

Abstract: A fluid flow machine has a main flow path in which at least one row of blades (2) is arranged, with at least one blade end of a blade row (2) being firmly connected to the main flow path confinement and, in an area of this fixed blade end at a sidewall (9), at least one longish, obstacle-type boundary layer barrier (11) is provided which in at least part of its course is oriented obliquely to the main flow direction, thereby deflecting fluid flowing near the sidewall towards the blade pressure side.

Abstract: A tandem blade design for an axial turbomachine, comprising a front blade and a rear blade disposed with an offset thereto in the circumferential direction and in the axial direction. The rear blade is profiled and positioned with respect to the front blade such that it raises the speed level at the trailing edge of the front blade in a predetermined working range in interaction with the front blade.

Abstract: A compressor for a turbocharger having a compressor wheel with compressor blades, and being mounted for rotation on a shaft. The compressor has a shroud mounted adjacent the wheel and defining a gas flow path between the shroud and the blades from a compressor inlet to a diffuser outlet. In cross-section the shroud has a surface in the flow path, the surface having a profile that includes a section with a smoothly curving surface and at least one relative discontinuity forming a downstream-facing face.

Abstract: A wind turbine blade having a longitudinal direction with a root end and a tip end as well as a chord extending in a transverse direction between a leading edge and a trailing edge is described. The blade comprises a flow control surface with a suction side and a pressure side. A number of boundary layer control structures are formed in the flow control surface. The boundary layer control structures include a channel submerged in the flow control surface with a first end facing towards the leading edge and a second end facing towards the trailing edge of the blade. The channel further comprises a bottom surface extending from the first end to the second end. The channel at the first end comprises a first channel zone comprising a first sub-channel having a first cross-sectional area and a second sub-channel having a second cross-sectional area, the first sub-channel and the second sub-channel crossing each other at a point of crossing.

Abstract: This disclosure relates to a gas turbine engine including a core engine that drives a fan. A fan nacelle surrounds the fan and provides an inner surface facing the fan. The fan nacelle includes an inlet lip adjoining the inner surface. A ring is arranged at the inner surface and is axially upstream from the fan. The ring includes a deployed position in which the ring is spaced radially inwardly from the inner surface to provide a gap therebetween through which air flows. The ring also includes a stowed position in which the ring is arranged radially inwardly from the deployed position and proximate to the inner surface. The ring is commanded to the deployed position in response to detecting a first condition, which corresponds to a flow separation condition at the fan nacelle inlet. The ring may be stowed during cruise conditions, for example.