Abstract: There is disclosed an inline axial flow fan including at least first and second axial flow fans and arranged in an inline manner along an axial direction of a rotational shaft of a rotational driving apparatus. A first flow control grid is arranged in a gas discharge side of the first axial flow fan, and a second flow control grid is arranged in a gas discharge side of the second axial flow fan. The first flow control grid has a stator blade having a smooth circular arc leading edge shape matching a circular arc shape of the stator blade of the first axial flow fan and a trailing edge shape extending in parallel with a gas flow direction. The second flow control grid has a stator blade having a smooth circular arc shape matching a circular arc shape of the stator blade of the second axial flow fan.

Abstract: A stacked wheel assembly for a turbine system includes a plurality of wheels. A stud includes a forward end having a circumferential surface with at least one relatively planar portion and a first groove extending circumferentially around at least a portion of the circumferential surface. A first nut is disposed proximate a forward face of one of the plurality of wheels to receive the forward end of the stud. A resilient arcuate member is configured to fittingly reside within the first groove. A lock plate having at least one slotted region is disposed proximate an outer surface of the lock plate to fittingly engage at least one lug disposed on a forward region of the first nut for rotationally retaining the stud and a second groove is disposed within an inner surface of the lock plate to receive the resilient arcuate member for axially retaining the lock plate.

Abstract: A rotor apparatus for extracting energy from bidirectional fluid flows comprises a first rotor (7) mounted for rotation about an axis of rotation (4) in a first direction of rotation, the first rotor (7) having at least one helical blade (2) with a pitch that decreases in a direction along the axis of rotation (4); and a second rotor (8) mounted for rotation about the same axis of rotation (4) in an opposite direction of rotation and having at least one helical blade (2) with a pitch that increases in the same direction along the axis of rotation (4), wherein fluid exiting the first rotor (7) is passed to the second rotor (8).

Abstract: A series fan assembly structure includes a first fan frame and a second fan frame. The first fan frame has a first latch section, a second latch section, a first engagement recess, a second engagement recess, a first retainer section and a second retainer section. The second fan frame has a third latch section, a fourth latch section, a third engagement recess, a fourth engagement recess, a third retainer section and a fourth retainer section. The first and second engagement recesses are respectively connected with the third and fourth latch sections, the first and second latch sections are respectively connected with the third and fourth engagement recesses and the first and second retainer sections are respectively connected with the third and fourth retainer sections. Accordingly, the first and second fan frames can be quickly assembled and securely connected in both axial direction and radial direction.

Abstract: A gas turbine engine has a fan rotor, a first compressor rotor and a second compressor rotor. The second compressor rotor compresses air to a higher pressure than the first compressor rotor. A first turbine rotor drives the second compressor rotor and a second turbine rotor. The second turbine drives the compressor rotor. A fan drive turbine is positioned downstream of the second turbine rotor. The fan drive turbine drives the fan through a gear reduction. The first compressor rotor and second turbine rotor rotate as an intermediate speed spool. The second compressor rotor and first turbine rotor together as a high speed spool. The high speed spool and the fan drive turbine configured to rotate in the same first direction. The intermediate speed spool rotates in an opposed, second direction.

Abstract: A propulsive fan system comprises a fan unit comprising a first stage array of rotatable blades upstream of a second stage array of rotatable blades. The first stage is coupled to a first drive means. The second stage is coupled to a second drive means. The first drive means is independently operable of the second drive means during operation of the fan system.

Abstract: A gas turbine engine has a fan rotor, a first compressor rotor and a second compressor rotor. The second compressor rotor compresses air to a higher pressure than the first compressor rotor. A first turbine rotor drives the second compressor rotor and a second turbine rotor. The second turbine drives the compressor rotor. A fan drive turbine is positioned downstream of the second turbine rotor. The fan drive turbine drives the fan through a gear reduction. The first compressor rotor and second turbine rotor rotate as an intermediate speed spool. The second compressor rotor and first turbine rotor together as a high speed spool, with the high speed spool rotating in an opposed direction to the intermediate speed spool. The fan drive turbine rotates in the same direction as the intermediate speed spool.

Abstract: A multi-stage impeller is configured in a multi-stage centrifugal compressor by fixing and attaching a plurality of centrifugal impellers to one rotating shaft. Diffusers and return channels are provided in order downstream from each impeller. The centrifugal impellers, the diffusers and the return channel are housed within a compressor casing. The return channels have a plurality of vanes positioned at intervals from one another in a circumferential direction, and at least two stages are provided. The vane exit angles monotonically increase toward the downstream stage.

Abstract: A rotor of a thermal fluid flow machine, especially a gas turbine, is provided. The rotor includes a plurality of rotor components that are held together by a common tie-bolt that extends through the center of the rotor components. The tie-bolt is fixed in at least one of the rotor components using at least one star spring that surrounds the tie-bolt in a circumferential direction.

Abstract: A gas turbine engine includes a shaft defining an axis of rotation. An outer turbine rotor directly drives the shaft and includes an outer set of blades. An inner turbine rotor has an inner set of blades interspersed with the outer set of blades. The inner turbine rotor is configured to rotate in an opposite direction about the axis of rotation from the outer turbine rotor. A splitter gear system couples the inner turbine rotor to the shaft and is configured to rotate the inner set of blades at a faster speed than the outer set of blades.

Abstract: A multi-stage axial compressor incorporating a counter-rotational movement is provided with a series of rotors mounted along and driven by a driveshaft, and a geared counter-rotating outer casing. A planetary gear system is assembled along a static casing, which can be assembled as a forward or aft casing for the compressor. The bearings of the planetary gear system typically will be aligned concentrically with a center rotor drum assembly mounted along the single driveshaft. The counter-rotating drum assembly will be assembled over the rotor drum assembly and will be engaged by the forward and aft casings so as to provide for counter-rotation of selected ones of the rotors driven by the driveshaft of the compressor.

Abstract: A paint drying booth includes a plurality of walls, a ceiling, and an access door for egress and ingress. A turbine generates heated compressed air which is delivered to the interior of the booth via a duct system. The duct is in fluid communication with an air knife having a slit which delivers a stream or sheet of air into the interior of the booth. More than one air knife can be provided, and the orientation of the plurality of air knives are coordinated to provide a flow of heated turbulent air within the booth to accelerate the drying of painted items within the booth. The turbine comprises a multi-stage compressor including a plurality of rotors and stators for compressing air passing therethrough. Optionally a pneumatic spray gun can be provided for painting the items within the booth as well.

Abstract: A turbomachine including at least one blade-row group that is arranged in the main flow path and at least two rows of blades that are adjacent to each other in the main flow direction, each row having a plurality of blades (38, 40), whereby a narrow cross section and a degree of overlap between the blades of the upstream row of blades and the blades of the downstream row of blades vary starting at the center of the main flow path in the direction of at least one main flow limiter.

Abstract: A turbomachine including at least one blade-row group that is arranged in the main flow path and at least two rows of blades that are adjacent to each other in the main flow direction, each row having a plurality of blades, whereby the trailing edges of the blades of the upstream row of blades and the leading edges of the blades of the downstream row of blades are arranged at an axial edge distance that decreases from the center of the main flow path in the direction of at least one main flow limiter.

Abstract: The invention relates to a turbine wheel arrangement for a gas turbine comprising two successive turbine wheels (18, 20) rotating in opposite directions, wherein the first turbine wheel (18) comprises flow channels (42) of a Laval cross-sectional shape, distributed over the circumference and having radially inner gas inlets (43) and radially further out gas outlets (45), in each case with a substantially tangential flow direction component, wherein the gas outlets (45) act an the second axially or radially acting turbine wheel (20) in the direction of flow. This has the effect that the thermal energy and compressive energy of the gas at the nozzle inlet is largely converted into flow energy at the outlet of the turbine stage. The rotational speeds of the two rotors coupled to the turbine wheels can be set as desired, allowing the operational states of the two systems to be optimally set without adjusting systems.

Abstract: A series fan assembly structure includes a first fan and a second fan mated with the first fan. The first fan includes a first frame body and at least one mating section diagonally positioned on two opposite corners of one side of the first frame body. The second fan includes a second frame body and at least one connection section diagonally positioned on two opposite corners of one side of the second frame body corresponding to the mating section. The connection section is connected with the mating section, whereby the series fan assembly structure is easy to rework and has better vibration absorption effect.

Abstract: A gas turbine engine includes in serial flow relationship: a first compressor provided with at least one row of compressor blades distributed circumferentially around the first compressor; a combustion chamber; and a first turbine provided with at least one row of turbine blades distributed circumferentially around the first turbine, wherein the first compressor and the first turbine are rotationally rigidly connected by a first shaft. The first turbine is adapted to influence a gas flow rate through the gas turbine engine depending on a rotational speed of the first turbine, wherein the gas turbine engine further includes an arrangement for controlling the rotational speed of the first turbine. A method for controlling a gas flow rate in an axial flow gas turbine engine is also provided.

Abstract: A compressor unit including a compressor housing, a compressor impeller, a gas diffuser channel, a cylinder-shaped rotating diffuser wall, and a supporting device. The compressor housing includes an air inlet and an air collection channel. The compressor impeller is installed in the compressor housing. The gas diffuser channel is disposed between the compressor impeller and the air collection channel and connected to the air collection channel. The cylinder-shaped rotating diffuser wall is disposed between an inner wall of the compressor housing and the compressor impeller and rotates in the same direction as the compressor impeller. The supporting device is disposed in the compressor housing to support the cylinder-shaped rotating diffuser wall. The compressor unit has high response speed, large air inlet flow, and high efficiency.

Abstract: A housing assembly for a fan unit includes an upper housing having a lower engaging portion adjacent to its lower end surface and a lower housing having an upper engaging portion adjacent to its upper end surface. When one of the upper and lower housings rotates relative to the other about a center axis of the housings in a first direction with the opposing end surfaces of the housings in axial contact, the lower and upper engaging portions engage with each other. While the lower and upper engaging portions are in engagement, one of the lower and upper engaging portions presses the other in both axial directions to cause elastic axial deformation of the other; and one of the lower and upper engaging portions presses the other toward both the first direction and a second direction opposite thereto to cause elastic circumferential deformation of the other.

Abstract: An object of the present invention is to enhance the capacity of a turbomolecular pump. A turbomolecular pump is a composite-type vacuum pump that combines a blade portion and a thread groove portion. Openings are formed at a joint portion between a rotor blade holding portion that holds rotor blades and a stepped portion that holds a rotor cylinder portion, such that the openings span both the rotor blade holding portion and the stepped portion. Part of the gas that is evacuated by the blade portions is evacuated by a thread groove portion that is formed of the rotor cylinder portion and a stator thread groove, and the rest of the gas is led into the rotor cylinder portion via the openings, and is evacuated by a thread groove portion that is formed of the rotor cylinder portion and another stator thread groove. Stress derived from rotation of a rotor can be withstood when the openings are formed at the joint portion between the rotor blade holding portion and the stepped portion.

Abstract: A high-efficiency, multi-stage centrifugal pump and method of assembly. The pump can include three pump stages with each one of the three pump stages including a front casing, a back casing, an impeller, and a bladed diffuser. The front casing and the back casing are removeably coupled around the impeller and the bladed diffuser. In the three-stage pump, the fluid can be pumped at a flow rate between about 300 liters per second and about 500 liters per second with an efficiency between about 86% and about 91%. The method includes separately casting, machining, and polishing each one of the front casing, the back casing, the impeller, and the bladed diffuser.

Abstract: An assembly is disclosed that includes a first rotating component and a second rotating component disposed adjacent to the first rotating component. An annular slot may be defined between the first and second rotating components and may include a sealing surface. Additionally, a seal may be disposed within the annular slot and may be configured to be engaged against the sealing surface when the first and second rotating components are rotated. Moreover, the seal may form a non-continuous ring within the annular slot when the seal is engaged against the sealing surface.

Abstract: A turbine includes a plurality of stacked disks, each disk comprising an opening in the center of the disk, which forms a central flow chamber. The turbine further includes a first disk that is coupled to a bottom of the plurality of stacked disks. The first disk does not have an opening in the center like the stacked disks. There is a plurality of disk spacers positioned between one or more of the plurality of stacked disks, thereby creating flow channels between the disks. The flow channels extend from an outside perimeter of the stacked disks to the central flow chamber. A tapered armature is coupled to the first disk and positioned within the central flow chamber, and a fluid collection unit is in communication with the outside perimeter of the stacked disks.

Abstract: A serial axial fan preferably includes a first impeller and a second impeller each having a plurality of blades radially extending with a predetermined rotation axis as the center, a first motor portion, a second motor portion, a first housing, and a second housing. The first motor portion has a first circuit board on which at least one electronic component arranged to control the driving of the first impeller is mounted. The second motor portion has a second circuit board on which at least one electronic component arranged to control the driving of the second impeller is mounted. The first and second circuit boards are electrically connected. The driving of the first impeller and the driving of the second impeller are controlled by the electronic component disposed on at least one of the first and second circuit boards.

Abstract: A turbomachine comprises a flow duct with coaxially arranged radially inner and outer endwalls, first and second sets of axially spaced rotor stages arranged between the inner and outer endwalls, and a plurality of variable endwall segments arranged along the inner endwall. The first set of rotor stages rotates in a first direction, and the second set rotates in a second direction. The first and second sets alternate in axial series along the flow duct, such that axially adjacent rotor stages rotate in different directions. The variable endwall segments are radially positionable, in order to regulate loading on the first and second sets of rotor stages by changing a cross-sectional flow area between the inner and outer endwalls.

Abstract: A regenerative pump (100) comprises at least one pump unit (105), the at least one pump unit comprising a casing or housing (110) comprising a fluid passage channel (115); and at least one impeller (120) provided inside the casing or housing for pumping the fluid through the fluid passage channel, wherein the casing or housing comprises at least one inlet channel (130) and at least one outlet channel (140) in communication with the fluid passage channel, the at least one inlet channel and/or the at least one outlet channel each comprising a first or axial portion (134) at least partially and preferably substantially parallel to an axis of rotation of the at least one impeller. The pump can be arranged in a single stage or multistage configuration, and has improved weight/size ratio and performance characteristics.

Abstract: A tandem fan-turbine rotor assembly for a tip turbine engine includes a hollow fan blade rotor and a solid fan blade rotor. The hollow fan blade rotor includes a first fan blade rotor hub, hollow fan blades, and an inducer. The solid fan blade rotor includes a second fan blade rotor hub, solid fan blades, an exo-ring, and tip turbine blades. The exo-ring connects the solid fan blades at their maximum outward radial extent. The tip turbine blades are connected to the exo-ring and extend radially outward from the exo-ring. The hollow fan blade rotor and the solid fan blade rotor rigidly attach to each other at the first and second fan blade rotor hubs.

Abstract: A system includes a multi-stage turbine. The multi-stage turbine includes a first turbine stage including a first wheel having a plurality of first blade segments spaced circumferentially about the first wheel, a second turbine stage including a second wheel having a plurality of second blade segments spaced circumferentially about the second wheel, and an interstage seal extending axially between the first and second turbine stages. The interstage seal is configured to be installed or removed while the first and second wheels remain in place in the respective first and second turbine stages.

Abstract: A serial axial fan includes first and second axial fans. Each of the first and second axial fans includes a base portion and a plurality of support ribs arranged to connect the base portions to housings. The first and second axial fans are coupled together with the base portions thereof either in contact with or in close proximity to each other. Each of the support ribs in each of the first and second axial fans extends over both housings of the first and second axial fans.

Abstract: A low pressure turbine for a gas turbine engine includes inner and outer counter-rotating rotor sets, with both said rotor sets driving a common shaft.

Abstract: A turboprop having at least one propeller formed by a set of variable pitch blades. Each blade is swivel-mounted on a rotary support and carries a gearwheel meshing with an actuator annulus rotating on the rotary support and coupled to a control annulus via an epicyclic mechanism.

Abstract: A gas turbine engine includes a low pressure compressor section and a high pressure compressor section. A low pressure turbine drives the low pressure compressor section. A gear arrangement is driven by the low pressure turbine to in turn drive a fan section. A pressure ratio across the low pressure compressor section is between about 4-8, and a pressure ratio across the high pressure compressor section is between about 8-15. In a separate feature, a compressor case includes a front compressor case portion and a rear compressor case portion, with the rear compressor case portion being axially further from an inlet case than the front compressor case portion. A support member extends between the fan section and the front compressor case portion.

Abstract: A stack of fan case in accordance with the present invention includes a first casing and a second casing stacked on the first casing. The first casing has a first surface, a second surface and a locking surface opposite to the second surface. An insertion bore formed on the second surface has an alignment bore, a fastening bore communicating to the alignment bore and a limit bump formed at the fastening bore. The second casing has a third surface, a fourth surface and at least one fastening member protruding on the fourth surface. The fastening member of the second casing is inserted into the alignment bore of the insertion bore to protrude on the locking surface of the first casing, and then casings are turned to make the fastening member pass through the limit bump and be accommodated within the fastening bore.

Abstract: A fan includes a first motor having a first rotor and a second motor having a second rotor which is rotationally connected to the first rotor. The fan further comprises a first impeller which, when driven by the first motor, rotates along a first direction and creates a main flow along a direction perpendicular to the periphery thereof and a tangential flow along the tangent thereof. The fan also includes a second impeller which, when driven by the second motor, rotates along the reverse direction of the first direction and impel the tangential flow to the direction perpendicular to the periphery of the first impeller.

Abstract: A flow-guiding device, connected between two fans disposed in series and rotating in the same rotation direction, includes a main frame and a plurality of flow-guiding pieces. The flow-guiding pieces are connected with the main frame. Each of the flow-guiding pieces is disposed corresponding to the stationary flow guiding device of the above fan so as to form a completed flow guiding device. A fan assembly including the flow-guiding device is also disclosed.

Abstract: A fan frame has at least one protrudent connector and at least one recessed connector. The at least one protrudent connector is formed on a corner of a surface of the fan frame. The at least one recessed connector is formed on another corner of the same surface of the fan frame, opposite to the at least one protrudent connector and corresponding to the at least one protrudent connector of another same fan frame. Two fan frames can be securely connected against each other by engaging corresponding protrudent and recessed connectors.

Abstract: A support frame portion is divided into a first support-frame half-portion and a second support-frame half-portion along a virtual reference dividing plane. A raised portion is integrally formed with each of side walls in a pair of the first web half-portion, projecting toward the second web half-portion beyond the virtual reference dividing plane. A raised portion is integrally formed with each of side walls in a pair of the second web half-portion, projecting toward the first web half-portion beyond the virtual reference dividing plane. A recessed portion is formed in each of the side walls in the pair of the first web half-portion, and is fitted with the raised portion corresponding thereto of the second web half-portion. A recessed portion is formed in each of the side walls in the pair of the second web half-portion, and is fitted with the raised portion corresponding thereto of the first web half-portion.

Abstract: A frame for a serially connected axial flow fan unit includes a first housing and a second housing coupled together. The first housing includes a first axial locking mechanism and a first unlocking mechanism, and the second housing includes a second axial locking mechanism and a second unlocking mechanism. The first and the second axial locking mechanism are locked against each other through their movement along their axis. The first and the second unlocking mechanism unlock the first and the second housing with a twisting force equal to or greater than a predetermined value when the first and the second housing are twisted relative to each other. When the first and the second end portion are brought into contact, the first and the second axial locking mechanism are locked against each other and the first and the second unlocking mechanism engage with each other.

Abstract: A jet engine includes a shaft rotatably supported in a bearing arrangement, a compressor and a turbine arranged on the shaft, and an electromechanical unit arranged centrally about the shaft axis to provide a motor function for starting the jet engine and/or a generator function for a power supply, and a function of an active magnetic bearing arrangement. The electromechanical unit is embodied as a transverse flux machine. The electromechanical unit preferably includes a rotor carrying permanent magnets and a stator with an undulating profiled stator surface.

Abstract: Electronic equipment frequently requires cooling to maintain the integrity and reliability of the equipment, and to elongate the life expectancy of the equipment. When in operation, the fan of a UAV creates airflow comprising outside air directed across the duct of the UAV. Utilizing this airflow generated by the fan of a UAV to provide heat transfer from a equipment enclosure accomplishes efficient heat transfer. The methods described herein for transferring heat from an equipment enclosure using an airflow generated by a fan of a UAV may be employed for UAVs having a variety of duct shapes, and having equipment enclosures inside the duct or in detachable equipment enclosures located on the duct of the UAV.

Abstract: A fan frame includes a first housing having a first end portion in which a first protrusion is arranged, a second housing having a second end portion in which a second protrusion opposing the first protrusion along a specified axis is arranged, the second end portion being in an axially opposing relationship with the first end portion, and a fixing member attached to the first protrusion and the second protrusion to fix the first housing and the second housing together. Further, a first locking portion is arranged in the first end portion and a second locking portion engaging with the first locking portion is arranged in the second end portion.

Abstract: A fastening device is used for connecting a first and a second fan together. The two fans each have an upper flange and a lower flange and a cylindrical body interconnecting the upper flange and the lower flange. The fastening device includes a plate-shaped pad and two resilient portions respectively extending perpendicularly from two opposite sides of the pad. The two resilient portions respectively extend through the lower flange of the first fan and the upper flange of the second fan, pressing against the first fan and the second fan toward each other. The pad is sandwiched between the lower flange of the first fan and the upper flange of the second fan.

Abstract: A turbine (5) having at least two sets of co-axially mounted, rotatable blades (10, 15) arranged so that one set cannot eclipse another. Preferably, the sets of blades (10, 15) are contra-rotatable. Each set of blades (10, 15) may be operable to extract similar amounts of energy, thereby to minimise the net reactive torque.

Abstract: A tip turbine engine (10) provides an axial compressor (22) having a compressor case (50) from which extend radially inwardly a plurality of outer compressor airfoils (54). The compressor case (50) is directly driven by the rotation of the turbine (32) and fan (28), while at least one gear (77) couples the rotation of the turbine (32) and fan (28) to an axial compressor rotor (46) having a plurality of inner compressor airfoils (52). In this manner, the axial compressor rotor (46) is driven in a direction opposite the direction of the outer compressor airfoils (54), thereby increasing the compression provided by the compressor without increasing the number of airfoils. The outer compressor airfoils (54) are formed on a plurality of outer airfoil assemblies (56) each having an arcuate substrate (58) from which the outer compressor airfoils (54) extend. Each of the outer compressor airfoil assemblies (56) includes more than one axially-spaced stage of outer compressor airfoils (54).

Abstract: The invention is for a continuous-combustion, closed-cycle, gas turbine engine with a regenerator and a displacer. It has embodiments that remove heater and cooler interior volumes during gas compression, which enable it to scale well to very large sizes. Low combustion temperatures insure very low emissions. The displacer levitated by an integral gas bearing and small clearance seal and given oscillatory translational motion by electromagnetic forces operates without surface wear. The turbine blades, subjected only to warm gases, are durable and inexpensive. Thus, this engine has a very long, continuous, maintenance-free service life. This gas turbine engine also operates without back work allowing high efficiency for both low and rated output. Pressurized encapsulation permits use of low-cost ceramics for high temperature components. The invention includes a unique monolithic ceramic heater, a compact high-capacity regenerator and a constant-power gas turbine.

Abstract: Orthogonal power unit contains a turbine with a shaft and blades of hydrofoil profile fixed around and along the shaft and the power generator. The turbine has six layers, and each layer has one blade fixed at the shaft. The blades of turbine layers are located uniformly in the peripheral direction around the turbine shaft forming three pairs of the adjacent blades. In each pair the blades are located at the opposite sides relative to the shaft, the blades in the utmost pairs have the same length L and the blades in the middle pair have the bigger length L0=L 20.25 each. The traverse masses of the middle and utmost blade pairs have the same ratio. The same balancing effect achieved by having the uniform length of all blades with the relative shift of balanced pairs of blades at 60° and with the uniform traverses masses.

Abstract: The present invention provides a supersonic compressor comprising a supersonic compressor rotor comprising a clockable rotor disk allowing restriction or opening of portions of a fluid flow channel of the rotor in order to enhance performance of the rotor during different operational stages, for example rotor start-up or steady state. The supersonic compressor rotor comprises a first rotor disk, a second rotor disk and a third rotor disk which share a common axis of rotation. The first and second rotor disks are rotatably coupled, and the third rotor disk is disposed between them. The third rotor disk is independently rotatable relative to said first and second disks, and comprises a raised surface structure for restricting or opening a portion of the flow channel defined by the rotor disks and at least two vanes. The flow channel comprises a supersonic compression ramp and encompasses the raised surface structure.

Abstract: In an axial-centrifugal compressor, the rotor of which includes an impeller, axial play is controlled by a special air ventilation to the rotor, by a circuit including two parallel arms, flow rates of which are both controlled by respective veins, and moreover the temperature in one of them is changed by a heat exchanger. The ventilation air is thus controlled, both in terms of temperature and flow rate.

Abstract: A counter-rotating blade stage in lieu of a stator stage may compensate for relatively low rotational speed of a gas turbine engine spool. A first spool may have at least two compressor blade stage and at least two turbine blade stage. A combustor is located between the at least two compressor blade stage and the at least two turbine blade stage along a core flowpath. The at least two counter-rotating compressor blade stage is interspersed with the first spool at least two compressor blade stage. A transmission couples the at least two additional compressor blade stage to the first spool for counter-rotation about the engine axis.

Abstract: Described herein are embodiments of a boundary layer effect turbine and a hydrodynamic speed reducer. Described is a boundary layer effect turbine that utilizes the phenomena of the boundary layer to drive a turbine impeller that is made of a plurality of spaced disks oriented along a rotatable shaft. As operating fluid is directed over surfaces of the plurality of disks of the boundary layer effect turbine, energy is transferred from the fluid to the disks as a result of the adhesive and viscous properties of the fluid.