Abstract: An intermediate turbojet case comprises a hub that supports removable panels and bleed lines, the hub comprising a flank provided with openings, each bleed line having an upstream end engaged in an opening in the flank and a downstream end terminated by a base plate through which it is fixed to an internal face of a removable panel by way of screws, each removable panel having a front edge at which it is fixed to an external lip of the hub by screws. At least one removable panel comprises a downstream edge supporting a retaining element close to the internal face to hold the base plate in contact with the internal face during a phase in which the removable panel is fixed to the hub by screwing, this phase preceding attachment of the base plate to the removable panel by screwing.

Abstract: An arrangement for intentionally mistuning a cavity formed adjacent an impeller in a turbomachine, the arrangement including at least two bladed elements defined within a perimeter of a casing wall adjacent the impeller, wherein the bladed elements are configured to mistune cavity acoustic modes to minimize acoustic pulsations in the cavity.

Abstract: A blower assembly includes a fan assembly configured to rotate about an axis and having a fan inlet ring that at least partially defines a fan inlet and a fan outlet. The blower assembly also includes a frame assembly coupled to the fan assembly and a recirculation damper coupled to the frame assembly. The recirculation damper and the fan inlet ring define an axial gap therebetween to reduce recirculation of an airflow discharged from the fan outlet.

Abstract: A system includes an airfoil disposed inside an engine assembly that includes a pressure side and a suction side that are coupled together at a leading edge and a trailing edge. The airfoil extends a radial length away from a central axis of the engine assembly between a hub end and a tip end. The airfoil includes a sweep feature disposed at the leading edge that is shaped to alter the air inside the engine assembly. Altering the air inside the engine assembly reduces a surface unsteady pressure level on the airfoil. The system includes a fan frame assembly comprising an inner and outer surface. The hub end is coupled with the inner surface and the tip end is coupled with the outer surface. The airfoil is integrated with the fan frame assembly such that the airfoil increases a structural load supporting capability of the fan frame assembly.

Abstract: In a fan case having an annular outer wall with a plurality of fan case bolt holes there through, bushings are inserted into the fan case bolt hole and are dimensioned to define an annular gap between the bolt hole inner surface and the bushing outer surface. An adhesive material disposed within each annular gap between the bushing and the corresponding fan case bolt hole, with the adhesive material forming a liquid shim separating the bushing outer surface from the bolt hole inner surface.

Abstract: A control system operable includes a modified primary control parameter for an aircraft, the control system includes: a primary control parameter leg configured to output a demand in an aircraft primary control parameter; a primary control parameter compensation leg configured to receive a change in absolute levels and/or spatial distributions of swirl angle and/or fan pressure at a primary control parameter relative to a reference and convert the change into the primary control parameter; a processor adapted to receive the demand in the primary control parameter output from the primary control parameter leg and the change to the primary control parameter output from the primary control parameter compensation leg; compare the demand in the primary control parameter output from the primary control parameter leg and the change to the primary control parameter output from the primary control parameter compensation leg; and generate a modified primary control parameter for the aircraft.

Abstract: A pump includes an axial inducer. The axial inducer includes a housing that has an internal surface that defines an axial fluid passage. A rotor is disposed about a central axis in the fluid passage. The rotor includes at least one blade that defines at least one blade tip. The internal surface of the housing defines a plurality of grooves adjacent the at least one blade tip. The grooves are elongated in a circumferential direction.

Abstract: An impeller includes Z blades, where Z is an integer equal to 5 or more, arranged in a circumferential direction of the impeller and extending radially, pitch angles between adjacent blades being all different. In terms of an arbitrary pitch angle ?, when a pitch angle ?1 adjacent to the pitch angle ?, and a pitch angle ?2 adjacent to the pitch angle ?, different from the pitch angle ?1, satisfy a relation, ?1<?2, a pitch angle ?1 different from the pitch angle ? adjacent to the pitch angle ?1 and a pitch angle ?2 adjacent to the pitch angle ?2, different from the pitch angle ?, satisfy a relation, ?2<?1.

Abstract: Devices, systems, and methods for making gas turbine engine component with high cycle fatigue performance include selecting target airfoils while detuning other airfoils. The selective detuning can reduce resource intensity for realistic testing during build. Conforming detuning masses can reduce the need for outside resources.

Abstract: A guide vane airfoil for placement in a flow path portion of a turbomachine is provided, which, relative to a flow pattern in flow path portion, has a leading edge and, downstream thereof, a trailing edge, as well as a suction side and a pressure side; relative to a longitudinal axis of the turbomachine, viewed in the axial direction, in a radially inner portion, forming a first angle ? with a circular arc about the longitudinal axis, and, in a radially outer portion, a second angle ? with a circular arc about the longitudinal axis. The guide vane airfoil is inclined in the outer portion, thus ??90°, in terms of absolute value, being >0° (|??90°|>0°), and the guide vane airfoil being more highly inclined in the outer portion than in the inner portion, thus ??90°, in terms of absolute value, being >??90° (|??90°|>??90°).

Abstract: An electronic device with a fan assembly is disclosed. The fan assembly includes an impeller and an insert separated from the impeller by a gap. The fan assembly increases airflow by rotationally driving the impeller. For a sufficient rotational speed of the impeller, the airflow reaches a level that provides a force that displaces the insert. The displacement may include movement and/or compression of the insert. As a result of the displacement, the gap between the impeller and the insert increases. The increased gap reduces the pressure and associated noise that is otherwise caused by the airflow. When the rotational speed of the impeller reduces or ceases, the insert returns to its initial position. In this manner, the fan assembly includes a self-adjusting gap that changes based on the airflow.

Abstract: A gas turbine engine for an aircraft has an engine core comprising turbine, compressor, and core shaft connecting the turbine to the compressor, the turbine being the lowest pressure turbine of the engine, and having turbine blades, and the compressor being the lowest pressure compressor of the engine; fan located upstream of the engine core; and gearbox that receives an input from the core shaft and outputs drive to the fan. The engine core further has three bearings arranged to support the core shaft, the three bearings having two rearward bearings located downstream of the leading edge of the lowest pressure turbine blade of the turbine at the root of the blade, and/or, when the turbine comprises four sets of turbine blades, downstream of the trailing edge of a turbine blade of the third set of turbine blades from the front of the turbine, at the root of the blade.

Abstract: A fan frame body with damping structure and a fan thereof. The fan frame body includes a fan frame main body having a first opening, a second opening, a flow way and a base section. The first and second openings are respectively positioned at the upper and lower ends of the fan frame main body. The flow way is disposed between the first and second openings in communication with the first and second openings. The base section is disposed at the second opening. A bearing cup and multiple static blades are perpendicularly disposed on the base section. Two ends of the static blades are respectively connected with the base section and the fan frame main body. Multiple damping structures are annularly disposed on an inner wall of the fan frame main body. The damping structures are raised body structures or recess structures.

Abstract: A method of health monitoring of a gas turbine engine includes mounting a detection system configured to detect an aeromechanical damping characteristic of a row of airfoils of a gas turbine. An actual aeromechanical damping characteristic of the row of airfoils is measured with the detection system. An output signal is generated indicative of the actual aeromechanical damping characteristic of the row of airfoils. A current flutter characteristic is determined based on the output signal indicative of the actual aeromechanical damping characteristic of the row of airfoils. An airfoil health monitoring system for gas turbine engine and a gas turbine engine are also disclosed.

Abstract: A nacelle inlet may comprise an aft bulkhead, an attachment ring extending in an aft direction from the aft bulkhead, an acoustic liner disposed radially inward from the attachment ring, the acoustic liner comprising a proximal skin, a distal skin, and a core disposed between the proximal skin and the distal skin, and a shroud extending longitudinally between a forward side of the shroud and an aft side of the shroud and extending circumferentially between a first end of the shroud and a second end of the shroud, wherein the shroud defines a plenum disposed between the acoustic liner and the shroud, the plenum is in fluid communication with the core via perforations in the distal skin. The plenum may serve to attenuate low frequency noise known as “buzz saw” tones and/or alleviate pressure resonance conditions that may cause structural damage to the engine fan blades.

Abstract: A fan assembly includes a shrouded fan rotor (18) having a plurality of fan blades (22) extending from a rotor hub (24) and rotatable about a central axis (20) of the fan assembly and a fan shroud (26) extending circumferentially around the fan rotor (18) and secured to an outer tip diameter of the plurality of fan blades (22). A stator assembly (28) is located downstream of the fan rotor (18), relative to an airflow (14) direction through the fan assembly. The stator assembly (28) includes a plurality of stator vanes (30) extending between a stator hub (32) and a stator shroud (34). A flow control ring (36) is positioned between the fan rotor (18) and the stator assembly (28) to block radial flow migration in an axial spacing between the fan rotor and the stator assembly resulting from a radial flow component of an airflow (14) exiting the fan rotor (18).

Abstract: A gas turbine engine for an aircraft has an engine core comprising turbine, compressor, and core shaft connecting the turbine to the compressor, the turbine being the lowest pressure turbine of the engine, and having turbine blades, and the compressor being the lowest pressure compressor of the engine; fan located upstream of the engine core; and gearbox that receives an input from the core shaft and outputs drive to the fan. The engine core further has three bearings arranged to support the core shaft, the three bearings having two rearward bearings located downstream of the leading edge of the lowest pressure turbine blade of the turbine at the root of the blade, and/or, when the turbine comprises four sets of turbine blades, downstream of the trailing edge of a turbine blade of the third set of turbine blades from the front of the turbine, at the root of the blade.

Abstract: A seal device according to the embodiment includes a seal fin provided between the rotation body and the stationary body and extending in a circumferential direction of the rotation body, and a swirl brake fin provided on the stationary body upstream of the seal fin. The swirl brake fin reduces a circumferential velocity component of the working fluid. The swirl brake fin has a negative pressure surface provided on a side of a rotation direction of the rotation body and a positive pressure surface provided on an opposite side to the negative pressure surface. The positive pressure surface extends in a direction opposite to the rotation direction of the rotation body from radially outward toward radially inward.

Abstract: A motor-fan assembly includes a motor assembly having a rotatable shaft extending therethrough and a working fan assembly having at least one working fan rotated by the rotatable shaft. The motor-fan assembly includes a motor cover that substantially encloses the motor assembly. The motor assembly provides a cover opening extending therethrough and the rotatable shaft extends through the opening. The motor-fan assembly also includes a cooling fan assembly with at least one cooling fan rotated by the rotatable shaft which fan draws cooling airflow over the motor assembly. A motor vent cover is coupled to the motor cover with the at least one cooling fan therebetween. The motor vent cover has a cooling air outlet through which cooling airflow is exhausted.

Abstract: A structural subassembly for a compressor of a turbomachine, which has a rotor having a plurality of blades, which extend radially in a flow path of the turbomachine, and a compressor casing, which forms a flow path boundary, which delimits the flow path through the turbomachine radially on the outside. In this subassembly, the compressor casing has casing structuring adjoining the rotor. It is envisaged that the compressor casing has a plurality of circumferential segments, which extend in the circumferential direction, wherein only one or only some of the circumferential segments forms or form casing structuring.

Abstract: A power transmission system includes a shaft, a stator disposed within the shaft and substantially concentric with the shaft; and at least one supporting element positioned between the stator and the shaft and configured to support the shaft on the stator to reduce a vibration of the shaft and allow the shaft to rotate relative to the stator. A gas turbine engine including the power transmission system is also described.

Abstract: A gas turbine engine includes a case assembly and a stator segment. The case assembly defines a first slot having a first surface and a second surface. The stator segment includes a shroud body axially extends between a first body end and a second body end. A first flange extends into the first slot. The first flange has a first flange first side, a first flange second side, a first flange first surface and a first flange second surface each circumferentially extending between the first flange first side and the first flange second side. A first portion of the first flange first surface engages the first surface. A second portion of the first flange first surface. A third portion of the first flange first surface is spaced apart from the first surface.

Abstract: A case for an industrial air blower provides noise-reducing foam baffles and vibration absorbing ductile mounting components, mitigating the substantial noise and vibration generated by the blower in operation. Configurable for use of the blower either as pressurized air supply or vacuum source, the case provides circulation of blower inlet air or vacuum outlet air around the blower motor, thereby aiding cooling of the blower motor, reducing the risk of overheating. When configured for use as a pressurized air supply, blower inlet air is heated by the blower motor, the blower thereby providing a heated pressurized air supply suitable for drying wet or water damaged surfaces. Embodiments provide caster wheels and handles for easy transport. Embodiments also provide a pressure relief valve or manometer cut-off to prevent blower overload from excessive pressure.

Abstract: A fan device includes a fan frame, an impeller, a plurality of cushion components, a plurality of first fasteners and a plurality of second fasteners. The fan frame includes a first frame body and a second frame body. The first frame body has a plurality of first engagement parts. The second frame body has a plurality of second engagement parts. The impeller is rotatably disposed on the fan frame. The cushion components are respectively located on different sides of the fan frame. The first fasteners are respectively disposed through the cushion components and engaged with the first engagement parts of the first frame body. The second fasteners are respectively disposed through the cushion components and engaged with the second engagement parts of the second frame body.

Abstract: A method for manufacturing an impeller of a rotary machine, the impeller including at least one vane limiting an inner channel, which is at least partly closed, the method includes successively manufactured the impeller of several material layers by a build-up process from a powder. The powder is applied in each case to a processing plane for the production of each material layer, and then a solid material layer is produced from the powder by a selective energy input, and structural orientation is determined for the impeller, according to which the impeller is built up in layers, and the structural orientation is defined by a first and a second angle, which angles describe the relative position of the impeller to the processing plane.

Abstract: A fluid supercharging device, comprising: a rotating shaft; a vane disc coaxially fixed to the rotating shaft; a plurality of fan blades fixed around a perimeter of the vane disc; the back side of the fan blades being provided with at least one fluid guiding inlet, an end of the back side distal from the vane disc is provided with a fluid guiding outlet, a fluid channel communicating the fluid guiding inlet with the fluid guiding outlet is provided along a lengthwise direction inside the fan blades; the fan blades rotate to generate a centrifugal force such that a fluid flows into the fluid channel via the fluid guiding inlet on the back side, and flows out of the fluid guiding outlet along the lengthwise direction of the fan blades.

Abstract: A diffuser-deswirler for a gas turbine engine is provided. The diffuser-deswirler includes an inner shell and an outer shell spaced apart and configured for receiving a flow of compressed air from a compressor of a gas turbine engine. A plurality of vanes extend between the inner shell and the outer shell to define a plurality of fluid passageways and a splitter extends along the circumferential direction between adjacent vanes to split the flow of compressed air passing through the each fluid passageway. All of these components are manufactured as a single monolithic piece and are configured for diffusing and deswirling compressor air before passing it to a combustor for an improved combustion process.

Abstract: There is disclosed a diffuser pipe assembly having: a plurality of diffuser pipes circumferentially distributed around the central axis and configured for diffusing a flow of compressed air received from an impeller, the diffuser pipes having a diffuser conduit for directing the flow of compressed air, the diffuser conduit curving between an inlet end and an outlet end along a conduit axis, the diffuser conduit having a baseline surface, a first subset of the diffuser pipes having aero-dampers protruding from the baseline surfaces of their diffuser conduits such that the diffuser pipes of the first subset have a natural vibration frequency different than a natural vibration frequency of at least a second subset of the diffuser pipes.

Abstract: A centrifugal blood pump without a mechanical bearing comprises a pump casing (1), an impeller (9) arranged in the pump casing rotatably about the central axis and freely movable axially and radially within a limited clearance. The impeller has permanent magnets or permanently magnetized magnetic regions (N/S) which cooperate with an electromagnetic drive to set the impeller rotating. A circular wall (12) or circularly arranged wall sections are provided within the pump casing, their inner surfaces defining a radial clearance together with the outer circumference of the impeller to form a hydrodynamic radial bearing for the impeller.

Abstract: An engine, having a first, second, third and fourth quasi-stage, each with a stator and a downstream rotor, wherein a particular blade/vane solidity in the center section is in the first quasi-stage, at least 1.04 and at most 1.16 for the stator and at least 1.46 and at most 1.67 for the rotor; in the second quasi-stage, at least 1.13 and at most 1.32 for the stator and at least 1.32 and at most 1.61 for the rotor; in the third quasi-stage, at least 1.20 and at most 1.39 for the stator and at least 1.16 and at most 1.41 for the rotor; in the fourth quasi-stage, at least 1.37 and at most 1.63 for the stator and at least 1.15 and at most 1.41 for the rotor.

Abstract: A fan having reduced discrete tone noise is disclosed. The fan includes a fan chassis having an air inlet and an air outlet formed open at an outer surface of the fan chassis; an impeller part provided in the fan chassis; a wall part forming an air passage, the air passage is provided in the fan chassis to allow air to be introduced through the air inlet by rotation of the impeller part to flow to the air outlet; and a resonator having a cavity part communicating with said air passage through a communication passage passing through the wall part.

Abstract: A contra-rotating fan structure includes a first base, a first fan, a second base, and a second fan. The first fan is rotatably disposed on the first base and includes a first hub. The first hub has a first largest width. The second fan is rotatably disposed on the second base and includes a second hub. The second hub has a second largest width. The first base and the second base are located between the first fan and the second fan. The second largest width is greater than the first largest width.

Abstract: A turbocharger including a compressor housing, a flange, an air bypass valve and a seal. The compressor housing has an impeller housing, an upstream passage positioned upstream of the impeller housing and a downstream passage positioned downstream of the impeller housing. The flange is coupled to the compressor housing and has a bypass passage connected to the downstream passage of the compressor housing and the upstream passage of the compressor housing. A groove is formed at a surface of the flange opposing the compressor housing and the seal is fitted into the groove. Therefore, a tight seal of the flange and the compressor housing can be ensured by the seal. Further, the air bypass valve is coupled only to the flange. Therefore, a tight seal of the turbocharger can be ensured easier than in a case where the air bypass valve is coupled over the flange and the compressor housing.

Abstract: An ultrashort nacelle configuration employs a fan cowl having an exit plane and a serrated trailing edge. A variable pitch fan is housed within the fan cowl. The variable pitch fan has a reverse thrust position inducing a reverse flow through the exit plane and into the fan cowl. The serrated trailing edge forms a plurality of vortex generators configured to induce vortices in the reverse flow.

Abstract: A heat dissipation module including a first fan and a second fan is provided. The first fan has a first hub and a plurality of first fan blades disposed on the first hub. The second fan has a second hub and a plurality of second fan blades disposed on the second hub. Herein the first hub and the second hub are movably connected to each other in an axial direction such that the first fan and the second fan coincide or are separated from each other.

Abstract: To achieve higher efficiency at a low-load region and to enable power saving throughout a year. The refrigeration cycle apparatus 1 includes a compressor 4 that has a flow in/out port 4d through which a refrigerant is capable of flowing out and flowing in, in fluid communication with a compression room 4c; pipes 21, 22 disposed at a suction side of the compressor 4; a pipe 25 connected to the flow in/out port 4d of the compressor 4; a pipe 27 that has one end connected to the pipe 25 and an opposite end connected to the pipe 21; and a second solenoid valve 13 for opening and closing a fluid passage of the pipe 27.

Abstract: Disclosed is a system including a turbine having a plurality of spokes. The first spoke end is coupled to a shaft and the second spoke end is coupled to a blade of a plurality of blades. Each blade is a cup with an open surface. A dispenser includes a combustion chamber. An air injector is configured to inject air into the combustion chamber. A fuel injector is configured to inject fuel into the combustion chamber. An ignitor is configured to supply a spark for combustion in the combustion chamber. A nozzle directs discharged fluid toward the open surface of the blade to drive the turbine. A housing encloses the second nozzle end and the plurality of blades, and has an exhaust pipe. A controller is configured to control the air injector, the fuel injector and the ignitor.

Abstract: A double-suction centrifugal fan includes: a first impeller coupled to a shaft; a second impeller provided with a second inlet port opened opposite to an electric motor and coupled to the shaft at a position farther from the electric motor than the first impeller; a first bell mouth connected to a first inlet port of the first impeller, and a second bell mouth connected to the second inlet port of the second impeller. An axial length L2 of the second bell mouth is greater than an axial length L1 of the first bell mouth.

Abstract: A positive-negative-rotation fan for a clothes dryer comprises multiple whole-size fan blades arranged on a periphery of an outer frame of the fan, and multiple half-size fan blades arranged on the periphery of the outer frame of the fan. The half-size fan blades and the whole-size fan blades have similar shapes, and the size of an edge of each half-size fan blade parallel to a radial direction of the fan is half of the size of a corresponding edge of the whole-size fan blade. The clothes dryer using the positive-negative-rotation fan can provide an even and great air volume and a great air intake pressure in a clockwise and counterclockwise alternating rotation process, and accordingly clothes are evenly dried and the drying time is short. By using a flow guide device, aggregated back-flows are not generated between the fan and an outlet of a volute.

Abstract: A centrifugal compressor includes: a rotor that includes a shaft rotatably disposed inside a casing and impellers fixed to an outer periphery of the shaft; a diaphragm that surrounds the impellers from an outer peripheral side; a suction-side casing head disposed separately from the diaphragm on a side on which fluid is sucked; a temperature controlling mechanism that is provided inside the suction-side casing head and is configured to control ambient temperature through flow of a heating medium; a heat insulating body disposed between the suction-side casing head and the diaphragm; and a locking structure that locks the heat insulating body and the suction-side casing head with each other to be relatively displaceable in a radial direction.

Abstract: A propulsion engine for an aeronautical vehicle defines a radial direction and a cooling air flowpath. The propulsion engine includes a power source; and a fan including a fan blade rotatable by the power source and extending generally along the radial direction, the fan blade defining an inlet, an outlet, and a cooling air passage extending between the inlet and the outlet and in airflow communication with the cooling air flowpath, the inlet being positioned inward from the outlet along the radial direction to provide a cooling airflow through the cooling air flowpath.

Abstract: A guide vane segment for a turbomachine stage that has an inner ring segment (10) and a plurality of guide vanes (20) that are configured on the inner ring segment; a detuning region (V) of the inner ring segment extending in each case from a trailing edge (21) of at least one guide vane (20), in particular of at least 50% of the guide vanes (50), axially toward a leading edge (22) of the guide vane (20) over at most 50% of a width (B) of the inner ring segment (10) and/or at most 5 mm and/or circumferentially on both sides, in each case over at most 25% of a spacing (A) between adjacent guide vanes (20), at and/or in which at least one cavity (112) is configured which contains at least one impulse element (100) with clearance of motion for providing impact contacts.

Abstract: An air-conditioning apparatus includes a housing having an air inlet and an air outlet, a fan disposed in the housing, and a bell mouth through which a fluid flowing from the air inlet to the air outlet passes in association with rotation of the fan. The bell mouth includes curved part having a curved sectional shape in a fluid flow direction and a vibration-damping element disposed on at least one of a front surface and a rear surface of the curved part. The vibration-damping element is disposed at a position corresponding to a node of vibration of the bell mouth.

Abstract: A flutter control system for a turbine includes a processor. The processor is configured to detect blade flutter of a turbine. The blade flutter indicates that blades of the turbine are in a deflected position different from a nominal operating position. The processor is configured to control operational parameters of the turbine that reduce or eliminate the blade flutter to improve the reliability and efficiency of the turbine.

Abstract: An object is to provide a vacuum pump that enables, without being affected by a flow rate of gas to be discharged, concentrated and efficient heating of only a stator component of an exhaust side gas channel that needs to be heated in order to prevent deposition of products and that also enables prevention of deposition of products in the exhaust side gas channel as a result of the heating, and improvement of pump emission performance. The vacuum pump has a rotor rotatably arranged on a pump base and a gas channel through which gas sucked by rotation of the gas is guided to an outlet port, and further includes heat insulating means for thermally insulating a stator component, which forms an exhaust side gas channel in the gas channel, from other components and heating means for heating the thermally insulated stator component.

Abstract: A cooking appliance includes an insulated cooking chamber positioned within a cabinet and an air plenum defined between the cabinet and the insulated cooking chamber. A fan assembly includes a first fan and a second fan positioned adjacent each other and having a void region immediately downstream of their outlets. The fan housings may be positioned in direct contact with each other such that the flows of cooling air exiting each fan interact with each other to reduce or eliminate expansion losses. Alternatively, the fan housings may be separated by a small airgap to reduce expansion losses while entraining additional cooling air.

Abstract: The disclosure provides a mount bracket which is configured for a fan. The mount bracket includes a button plate, a frame and a plurality of vibration-absorbing components. The button plate is mounted with a motor mount. The frame surrounds the button plate, and the frame has an inner lateral surface and an outer lateral surface. A plurality of fixing structures protrude from the outer lateral surface of the frame. The inner lateral surface of the frame and an outer lateral surface of the button plate form an annular gap therebetween. The vibration-absorbing components are spaced apart from each other and located in the annular gap, and the vibration-absorbing components are located between and connected to the outer lateral surface of the button plate and the inner lateral surface of the frame.

Abstract: A blower has a centrifugal multi-blade fan that has blades around a rotation axis and a casing that houses the centrifugal multi-blade fan. The centrifugal multi-blade fan satisfies a relation of d1/h1?5, in which d1 is a diameter of a part having the blades, and h1 is a height of the blades in an axial direction of the rotation axis. A part of the casing on one side in an axial direction of the centrifugal multi-blade fan has an air suction port. A part of the casing on the radial outer side of the centrifugal multi-blade fan has an air passage through which air blown from the centrifugal multi-blade fan flows. The casing has an enlargement portion that enlarges the air passage on at least one of the one side and an other side in the axial direction as the casing extends toward the radial outer side.

Abstract: According to one embodiment, a noise reduction device includes speakers, microphones, and a processing circuit. The speakers are arranged around a rotor and emit control sound based on control signals. The microphones are arranged around the rotor and convert the control sound and noise emitted by the rotor into microphone signals. The processing circuit generates the control signals for reducing acoustic power in positions of the microphones, based on the microphone signals, rotation speed of the rotor, and a phase of noise that reaches the microphones from the rotor.

Abstract: A rotor includes a plurality of airfoils and each airfoil has a span that extends from 0% at a root to 100% at a tip, a chord that extends from 0% at a leading edge to 100% at a trailing edge and a pressure side opposite a suction side. The pressure side of each airfoil has a pressure side surface shape and the suction side of each airfoil has a suction side surface shape based on an operating state of the rotor. Each airfoil has the same suction side surface shape between 10% and 90% of the chord and between 80% and 100% of the span at a first state. At least one first airfoil has a different suction side surface shape between 10% and 90% of the chord and between 80% and 100% of the span than at least one second airfoil at a static state of the rotor.