Rotary airfoil assembly having an opening formed therein to jet or draw air

Abstract

A rotating airfoil assembly includes a rotation axis and a plurality of rotating airfoils configured to rotate about the rotation axis. Each of the rotating airfoils includes a leading edge, a trailing edge, a suction surface between the leading edge and the trailing edge, and a pressure surface between the leading edge and the trailing edge. The suction surface and the pressure surface are positioned on opposite sides of the rotating airfoil such that the rotating airfoil generates lift when air flow flows over the suction surface and the pressure surface of the rotating airfoil as the rotating airfoil rotates about the rotation axis. At least one opening is located on one of the suction surface or the pressure surface. The at least one opening is configured to eject air or draw air into the opening.

Description

Technical Field

[0001] This disclosure relates to a rotating airfoil assembly, specifically, a rotating airfoil assembly for an engine that generates thrust for an aircraft, such as a fan or propeller. Background Technology

[0002] The thrust used to move an aircraft through the air can be generated by multiple airfoil elements rotating about a central axis, such as fan blades in a ductless single-fan engine or a propeller on a propeller-driven aircraft. When the fan or propeller rotates, some blades travel in a downward direction, while others travel in an upward direction. When the aircraft is in flight level, air flows into the fan or propeller along its axial direction, and the downward-traveling blades and the upward-traveling blades produce equal amounts of thrust. However, when the aircraft has an angle of attack, air flows into the fan or propeller with a non-axial component, and the downward-traveling blades produce a different thrust than the upward-traveling blades. For example, when the aircraft pitches upward, such as during takeoff, the downward-traveling blades produce greater thrust than the upward-traveling blades, resulting in asymmetric loads on the fan blades or propeller. Therefore, in one rotation, the rotating airfoil (fan blade or propeller) experiences a differential load (1P load), creating cyclic load conditions for the rotating airfoil. Among other things, these cyclic loads can subject rotating airfoils to fatigue stress and strain. Attached Figure Description

[0003] The features and advantages of this disclosure will become apparent from the following description of various exemplary embodiments, as illustrated in the accompanying drawings, wherein the same reference numerals generally denote the same, functionally similar and / or structurally similar elements.

[0004] Figure 1 This is a schematic perspective view of an aircraft having a ductless single-fan engine with a rotating airfoil assembly, according to an embodiment of the present disclosure.

[0005] Figure 2 It is along Figure 1 The line 2-2 in the middle is cut off Figure 1 A schematic cross-sectional view of one of the ductless single-fan engines of the aircraft shown.

[0006] Figure 3 This is a schematic perspective view of an aircraft having a ductless single-fan engine with a rotating airfoil assembly, according to an embodiment of the present disclosure.

[0007] Figure 4 This is a schematic perspective view of an aircraft having a turboprop engine with a rotating airfoil assembly, according to an embodiment of the present disclosure.

[0008] Figure 5 This is a schematic perspective view of an aircraft having a ducted turbofan engine with a rotating airfoil assembly, according to an embodiment of the present disclosure.

[0009] Figure 6 yes Figure 6 One of the ducted turbofan engines of the aircraft shown runs along... Figure 5 A schematic cross-sectional view taken from line 6-6 in the figure.

[0010] Figure 7 This is a side view of a rotating airfoil according to an embodiment of the present disclosure.

[0011] Figure 8 yes Figure 7 The top view of the rotating airfoil shown.

[0012] Figure 9A , 9B Figures 9 and 9C are top views of rotating airfoils, each with openings of different orientations and positions within the airfoil.

[0013] Figure 10 It is along Figure 2 The line 10-10 is cut off Figure 2 A schematic cross-sectional view of the fan (rotating airfoil assembly) of the ductless single-fan engine of the aircraft shown.

[0014] Figure 11 It is along Figure 2 A schematic cross-sectional view taken by line 10-10 in the figure shows... Figure 2 Another embodiment of the fan (rotary airfoil assembly) of the ductless single-fan engine of the aircraft shown.

[0015] Figure 12 It is along Figure 2 A schematic cross-sectional view taken by line 10-10 in the figure shows... Figure 2 Another embodiment of the fan (rotary airfoil assembly) of the ductless single-fan engine of the aircraft shown. Detailed Implementation

[0016] The features, advantages, and embodiments of this disclosure will be apparent or obvious upon consideration of the following detailed description, accompanying drawings, and claims. Furthermore, it should be understood that the following detailed description is exemplary and intended to provide further explanation without limiting the scope of the claimed disclosure.

[0017] Various embodiments are discussed in detail below. Although specific embodiments are discussed, they are for illustrative purposes only. Those skilled in the art will recognize that other components and constructions can be used without departing from the spirit and scope of this disclosure.

[0018] As described above, rotating airfoils, such as fan blades of a turbofan engine fan or propellers on a propeller-driven aircraft, can experience differential loads (IP loads) during rotation when the airfoil is angled (e.g., tilted upwards or downwards) relative to the airflow entering the fan or propeller about its axis of rotation. The embodiments discussed herein reduce the magnitude of the asymmetric load generated by the rotating airfoil under such conditions. In the embodiments discussed herein, air is ejected from the outer surface of the rotating airfoil to disrupt the airflow passing through that outer surface. In some embodiments, air may be ejected from the suction side of the rotating airfoil moving upwards in a pitch-up state, thereby reducing the amount of thrust generated by the blades during this state. In other embodiments, air may be ejected from the pressure side of the rotating airfoil moving downwards in a pitch-up state, thereby increasing the amount of thrust generated by the blades during this state.

[0019] The rotating airfoil discussed in this article applies to rotating airfoil assemblies that generate thrust for fixed-wing aircraft, particularly open rotor engines such as propeller or ductless fan engines. Figure 1 This is a perspective view of an aircraft 10 that can be implemented in various preferred embodiments. The aircraft 10 includes a fuselage 12, a pair of wings 14 attached to the fuselage 12, and a tail 16. The aircraft 10 also includes a propulsion system that generates the thrust required to propel the aircraft 10 in flight during taxiing operations, and others. Figure 1 The propulsion system of the aircraft 10 shown includes a pair of engines 100. In this embodiment, each engine 100 is attached to one of the wings 14 via an underwing-mounted pylon 18. Although the engines 100 are... Figure 1 As shown in the diagram, the engine 100 is attached to the wing 14 via an underwing configuration. In other embodiments, the engine 100 may have an alternative configuration and be connected to other parts of the aircraft 10. For example, the engine 100 may additionally or alternatively include one or more aspects connected to other parts of the aircraft 10, such as, for example, the tail fin 16 (e.g., Figure 3 (as shown) and fuselage 12.

[0020] The following will refer to Figure 2 To describe further, Figure 1 The engine 100 shown is a ductless single-fan engine, each capable of selectively generating thrust for the aircraft 10. The amount of thrust can be controlled, at least in part, based on the amount of fuel supplied to the ductless single-fan engines via fuel system 130 (see [link to fuel system]). Figure 2 The aircraft turbine fuel discussed in this embodiment is a combustible hydrocarbon liquid fuel with the desired carbon number, such as kerosene-based fuel. The fuel is stored in fuel tank 131 of fuel system 130. Figure 1As shown, at least a portion of the fuel tank 131 is located in each wing 14, and a portion of the fuel tank 131 is located in the fuselage 12 between the wings 14. However, the fuel tank 131 may be located in other suitable locations within the fuselage 12 or the wings 14. The fuel tank 131 may also be entirely located within the fuselage 12 or the wings 14. The fuel tank 131 may also be a separate tank rather than a single unit; for example, two tanks may each be located within a respective wing 14.

[0021] Figure 2 yes Figure 1 A schematic cross-sectional view of one of the engines 100 used in the propulsion system of the aircraft 10 shown. Figure 2 The cross-sectional view is along Figure 1 The line 2-2 in the diagram is cut off. As mentioned above, engine 100 is a ductless single-fan engine. The ductless single-fan engine 100 has an axial direction A (extending parallel to the longitudinal centerline 101, in...) Figure 2 (Shown for reference), radial direction R and circumferential direction. Circumferential direction ( Figure 2 (Not depicted in the text) extends in the direction of rotation about the longitudinal centerline 101. The ductless single-fan engine 100 includes a fan section 102 and a turbine 104 disposed downstream of the fan section 102.

[0022] Figure 2 The turbine 104 depicted includes a tubular housing 106 (also referred to as a casing or nacelle) defining an inlet 108. In this embodiment, the inlet 108 is annular. The housing 106 surrounds an engine core that includes, in series flow relationships: a compressor section including a turbocharger or low-pressure (LP) compressor 110 and a high-pressure (HP) compressor 112; a combustion section 114; a turbine section including a high-pressure (HP) turbine 116 and a low-pressure (LP) turbine 118; and an exhaust nozzle section 120. The compressor section, combustion section 114, and turbine section together at least partially define a core airflow path 121 extending from the inlet 108 to the exhaust nozzle section 120. The turbine 104 also includes one or more drive shafts. More specifically, turbine 104 includes a high-pressure (HP) shaft or spool 122 that drives an HP turbine 116 to an HP compressor 112, and a low-pressure (LP) shaft or spool 124 that drives an LP turbine 118 to an LP compressor 110.

[0023] A ductless single-fan engine 100, more specifically, a turbine 104, can operate in conjunction with and receive fuel flow from a fuel system 130. The fuel system 130 includes a fuel delivery assembly 133 that supplies fuel flow from a fuel tank 131 to the ductless single-fan engine 100, and, more specifically, to a plurality of fuel nozzles 142 that inject fuel into the combustion chamber of the combustor 140 in the combustion section 114 (see [link to previous section]). Figure 3 (To be discussed further below). The fuel delivery assembly 133 includes pipes, tubes, conduits, etc., to fluidly connect various components of the fuel system 130 to the ductless single-fan engine 100. The fuel tank 131 is configured to store hydrocarbon fuel, and the hydrocarbon fuel is supplied from the fuel tank 131 to the fuel delivery assembly 133. The fuel delivery assembly 133 is configured to deliver hydrocarbon fuel between the fuel tank 131 and the ductless single-fan engine 100, and thus provides a flow path (fluid path) for the hydrocarbon fuel from the fuel tank 131 to the ductless single-fan engine 100.

[0024] Fuel system 130 includes at least one fuel pump fluidly connected to fuel delivery assembly 133 to direct fuel flow through fuel delivery assembly 133 to the ductless single-fan engine 100. One such pump is a main fuel pump 135. The main fuel pump 135 is a high-pressure pump that is the primary source of pressure increase in the fuel delivery assembly 133 between fuel tank 131 and ductless single-fan engine 100. The main fuel pump 135 may be configured to increase the pressure in fuel delivery assembly 133 to a pressure greater than the pressure inside the combustion chamber of burner 140.

[0025] Fuel system 130 also includes a fuel metering unit 137 in fluid communication with fuel delivery assembly 133. Any metering unit 137 can be used, including, for example, a metering valve. The metering unit 137 is located downstream of main fuel pump 135 and upstream of fuel manifold 139, which is configured to distribute fuel to fuel nozzles 142. Fuel system 130 is configured to supply fuel to metering unit 137, and metering unit 137 is configured to receive fuel from fuel tank 131. Metering unit 137 is further configured to supply a fuel flow to ductless single-fan engine 100 in a desired manner. More specifically, metering unit 137 is configured to meter fuel and supply a desired volume of fuel to fuel manifold 139 of ductless single-fan engine 100 at, for example, a desired flow rate. Fuel manifold 139 is fluidly connected to fuel nozzles 142 and distributes (supplyes) the received fuel to a plurality of fuel nozzles 142, where the fuel is injected into the combustion chamber and burned. The regulating fuel metering unit 137 changes the volume of fuel supplied to the combustion chamber, thus changing the amount of propulsive thrust generated by the ductless single-fan engine 100 to propel the aircraft 10.

[0026] The ductless single-fan engine 100 also includes various auxiliary systems to assist in the operation of the ductless single-fan engine 100 and / or the aircraft 10. For example, the ductless single-fan engine 100 may include a main lubrication system 152, a compressor cooling air (CCA) system 154, an active thermal gap control (ATCC) system 156, and a generator lubrication system 158, each in... Figure 2 The diagram is schematically shown. The main lubrication system 152 is configured to provide lubricant to various bearings and gear meshes, such as in the compressor section, turbine section, HP spool 122, and LP spool 124. The lubricant provided by the main lubrication system 152 can increase the service life of these components and can remove a certain amount of heat from these components by using one or more heat exchangers. The compressor cooling air (CCA) system 154 supplies air from one or both of the HP compressor 112 or LP compressor 110 to one or both of the HP turbine 116 or LP turbine 118. An active thermal clearance control system 156 is used to minimize the clearance between the turbine blade tips and the casing wall as the casing temperature varies during flight missions. The generator lubrication system 158 provides lubrication to an electric generator (not shown) and provides cooling / de-heating to the electric generator. The electric generator can provide power to, for example, a starter motor for the ductless single-fan engine 100 and / or various other electronic components of the ductless single-fan engine 100 and / or the aircraft 10. The lubrication system for the ductless single-fan engine 100 (e.g., the main lubrication system 152 and the generator lubrication system 158) can be lubricated using hydrocarbon fluids (e.g., oil), wherein the oil circulates through the inner surface of the oil sweeping line.

[0027] The fan section 102 of the ductless single-fan engine 100 includes a rotator 160. A plurality of fan blades 162 are connected to the rotator 160. More specifically, the rotator 160 includes a fan hub 164, and the fan blades 162 are coupled to the fan hub 164 (or disc). The fan blades 162 and the fan hub 164 are circumferentially rotatable together about a rotation axis 161, which in this embodiment coincides with the longitudinal centerline (axis) 101. The rotator 160 rotates relative to the housing 106. Each fan blade 162 is an airfoil, more specifically, a rotating airfoil. In this embodiment, the fan blades 162, together with the fan hub 164, constitute a rotating airfoil assembly.

[0028] The turbine 104 in this embodiment is a torque-generating system that produces torque to rotate fan blades 162. The turbine 104 is configured to operate (e.g., rotate) a rotator 160. The rotator 160 may be coupled to a shaft, and more specifically, to an LP shaft 124 of the turbine 104, which rotates the fan blades 162 and the fan hub 164. In some embodiments, the LP shaft 124 may be coupled to the rotator 160 in a direct-drive configuration; however, in this embodiment, the LP shaft 124 is coupled to a gearbox 126, which in turn transmits rotational (torsional) force to rotate the rotator 160.

[0029] One or more outlet guide vanes 166 may be connected to the housing 106. In this embodiment, the outlet guide vanes 166 are positioned at the tail of the fan blades 162. In this embodiment, the housing 106 is stationary such that the one or more outlet guide vanes 166 do not rotate about the longitudinal centerline 101, and are therefore stationary relative to rotation about the longitudinal centerline 101. Although the outlet guide vanes 166 are stationary relative to the longitudinal centerline 101, the outlet guide vanes 166 are capable of rotating or moving relative to the housing 106.

[0030] During the operation of the fanless engine 100, air flows from... Figure 2 The left side flows towards Figure 2 On the right side. A portion of the airflow may flow over the fan blades 162 and the outlet guide vanes 166. A portion of the airflow may enter the housing 106 through the annular inlet 108 as air flowing through the core airflow path 121 to mix with fuel for combustion in the combustion chamber 140, and be discharged through the injection exhaust nozzle section 120. As described above, the outlet guide vanes 166 may be movable relative to the housing 106 to guide the airflow in a particular direction. Each outlet guide vane 166 may be movable to adjust the tilt, pitch, sweep, or any combination thereof of the outlet guide vane 166.

[0031] Figure 3 A schematic diagram of an aircraft 10 with a ductless single-fan engine 100A is shown, which has an alternative configuration for a ductless single-fan (USF) engine. Figure 1 and Figure 2 In the illustrated embodiment, the front end or front portion of the housing 106 includes one or more fan blades 162 and one or more outlet guide vanes 166. In other embodiments, the one or more fan blades 162 and one or more outlet guide vanes 166 may have a different arrangement relative to the housing 106. For example, in Figure 3In the illustrated embodiment, one or more fan blades 162 and one or more outlet guide vanes 166 may be located at the rear end or rear portion of the housing 106, for example, coupled to the rear portion of the housing 106. The ductless single-fan motor 100A may include... Figure 1 and Figure 2 All the features, and can have with Figure 1 and Figure 2 The components and operation are similar to those of the ductless single-fan engine 100. However, in Figure 3 In this housing 106, one or more fan blades 162 and one or more outlet guide vanes 166 are located at the rear end or rear portion of the housing 106. More specifically, one or more fan blades 162 and one or more outlet guide vanes 166 may be coupled to the rear portion of the housing 106.

[0032] In other embodiments, the engine according to this disclosure may be configured to have stationary blades positioned in front of the rotating fan blades 162 (therefore, blade 166 is an inlet guide vane). Although the outlet guide vane 166 may be stationary rather than rotating about the longitudinal centerline 101, as described above, one or more outlet guide vanes 166 may rotate in the opposite direction relative to one or more fan blades 162, such that the one or more outlet guide vanes 166 are counter-rotating rotors in a counter-rotating open rotor (CROR) engine. A propeller configuration in which the rotor is located in front of the pylon 18 is conceivable, as is an extender configuration in which the rotor is located behind the pylon 18. In this case, the counter-rotating rotor may also be a rotating airfoil as part of a rotating airfoil assembly, as discussed further below.

[0033] Figure 4This is a schematic perspective view of a propeller-driven aircraft 10. In this embodiment, the aircraft is driven by a turboprop engine 200. Each turboprop engine 200 in this embodiment includes a turbine 104 and a propeller assembly 210. The propeller assembly 210 includes a plurality of propeller blades 212 connected in a radial direction R to and extending outward from a propeller shaft 214. The turbine 104 is a torque-generating system for the propeller assembly 210. The turbine 104 of the turboprop engine 200 is similar to the turbine 104 discussed above, and detailed descriptions of these components are omitted here because the discussion above also applies to the turboprop engine 200. The turbine 104 is configured to operate (e.g., rotate) the propeller assembly 210 (more specifically, the propeller shaft 214) about a rotation axis 216 of the propeller shaft 214. In this embodiment, the rotation axis 216 coincides with the longitudinal centerline 101 of the turbine 104; however, in other embodiments, the rotation axis 216 may be parallel to the longitudinal centerline 101. Although in a direct-drive configuration, the drive shaft 214 may be directly coupled to the turbine 104, such as the LP shaft 124, the turbine 104, more specifically, the LP shaft 124, is coupled to a gearbox 126, which in turn transmits rotational (torsional) forces to rotate the drive shaft 214. The propeller blades 212 are airfoils, more specifically, rotating airfoils, and the propeller assembly 210 is another example of a rotating airfoil assembly. The propeller assembly 210 is an open rotor system that can also withstand asymmetric loads on the propeller blades 212, wherein the longitudinal centerline 101 of the turboprop engine 200 is at an angle (e.g., pitched up or down) relative to the airflow entering the propeller assembly 210.

[0034] Figure 5 This is a stereoscopic view of the aircraft 10, which is powered by the turbofan engine 202. Figure 6 yes Figure 5 A schematic cross-sectional view of one of the turbofan engines 202 used in the propulsion system of the aircraft 10 shown. Figure 6 The cross-sectional view is along Figure 5 The line 6-6 in the middle was cut off. For Figure 5 and 6 In the embodiment described herein, turbofan engine 202 is a high bypass ratio turbofan engine. Turbofan engine 202 includes a fan section 220 and a turbine 104 disposed downstream of the fan section 220. The turbine 104 of turbofan engine 202 is similar to the turbine 104 discussed above, and detailed descriptions of those components are omitted here because the above discussion also applies to turbofan engine 202.

[0035] Figure 6The illustrated fan section 220 includes a fan 222 having a plurality of fan blades 224 connected to a disk 226. The fan blades 224 and disk 226 are rotatable together about a rotation axis 221, which in this embodiment coincides with a longitudinal centerline (axis) 101. An LP shaft 124 is connected to disk 226 to rotate the fan blades 224 and disk 226. Disk 226 is covered by a rotatable front hub 228 having an aerodynamic profile to facilitate airflow through the plurality of fan blades 224. Furthermore, an annular fan housing or nacelle 230 is provided, circumferentially surrounding at least a portion of the fan 222 and / or turbine 104. The nacelle 230 is annular and defines an inlet 232 for the fan section 220. While the nacelle 230 may be symmetrical, the nacelle 230 and the inlet 232 may also be asymmetrical, such as vertically asymmetrical or horizontally asymmetrical. The outer nacelle 230 is supported relative to the turbine 104 by a plurality of circumferentially spaced outlet guide vanes 234. A downstream section 236 of the outer nacelle 230 extends above and outside the turbine 104 to define a bypass airflow passage 238 therebetween. The fan blades 224 are airfoils, more specifically rotating airfoils, and the fan 222 is another example of a rotating airfoil assembly.

[0036] air from Figure 6 The left side flows towards Figure 6 On the right side. A portion of the airflow can pass through the bypass airflow passage 238 over the fan blades 224 and the outlet guide vane 234. As described above, as air flows through the core airflow path 121 to mix with fuel for combustion in the combustor 140 and exits through the exhaust nozzle section 120, a portion of the airflow can enter the outer casing 106 through the annular inlet 108. The outer nacelle 230 helps to guide the airflow into the fan blades 224 of the fan 222, even when the turbofan engine 202 and the aircraft 10 are pitching up or down. Therefore, when the fan 222 is at an angle (e.g., pitching up or down) relative to the airflow entering the inlet 232 of the fan section 220 about its longitudinal centerline 101 of rotation, the fan 222 of the turbofan engine 202 is not subjected to the significant asymmetric load conditions as the open rotor rotating airfoil assembly discussed above. Nevertheless, rotating airfoils and rotating airfoil assemblies can also be used as the fan 222 of the turbofan engine 202.

[0037] The above discussion is used for Figures 1 to 6Each torque-generating system of the engines 100, 100A, 200, and 202 shown is a turbine 104. However, other suitable torque-generating systems can be used for rotating airfoils (e.g., fan blades 162, 222 and propeller blades 212) and rotating airfoil assemblies (e.g., rotator 160, propeller assembly 210, and fan 222). Other suitable torque-generating systems include other engines, such as reciprocating engines. Although Figure 1 and 3 The aircraft 10 shown in Figures 4 and 5 is an airplane, but the embodiments described herein are also applicable to other aircraft 10, including, for example, other fixed-wing unmanned vehicles (UAVs). Furthermore, although not described herein, in other embodiments, the embodiments discussed herein are applicable to any rotating airfoil and rotating airfoil assembly, such as wind turbine blades.

[0038] Figure 7 and Figure 8 This shows what can be used in airfoil assembly 300 (see example). Figure 10 Rotating airfoil components 310, such as the rotator 160, propeller assembly 210 and fan 222 discussed above. Figure 7 This is a side view of the rotating airfoil 310. Figure 8 This is a top view of the rotating airfoil 310. The rotating airfoil 310 includes a leading edge 312, a trailing edge 314, a root 316, and a tip 318. The rotating airfoil 310 is connected at its root end to a central support, such as a fan hub 164, a propeller shaft 214, or a disk 226, around which the rotating airfoil 310 rotates. The rotating airfoil 310 is located in the radial direction R( Figure 2 The airfoil extends outward from the root 316 to the tip 318. The rotating airfoil 310 includes a suction side 322 and a pressure side 324, and the surfaces of the rotating airfoil 310 are formed on the suction side 322 and the pressure side 324, respectively, between the leading edge 312 and the trailing edge 314. These surfaces are the suction surface 326 and the pressure surface 328. Figure 8 As can be seen, the rotating airfoil 310 is an arc-shaped airfoil with a convex curvature on its suction surface 326 and a generally flat pressure surface 328. However, the rotating airfoil 310 can have any suitable shape, including, for example, a concave surface, and the rotating airfoil 310 can be a symmetrical airfoil. The suction surface 326 and the pressure surface 328 are located on opposite sides of the rotating airfoil 310, such that when the rotating airfoil 310 rotates about the rotation axis 301, airflow flows over the suction surface 326 and the pressure surface 328 of the rotating airfoil 310, and the rotating airfoil 310 generates lift (thrust).

[0039] The rotating airfoil 310 includes at least one opening 332, which is formed in one of the suction surface 326 or the pressure surface 328. In this embodiment, the rotating airfoil 310 includes a plurality of openings 332. Figure 7 As shown, two openings 332 are located on the suction surface 326. Each opening 332 is fluidly connected to an air source, for example, through a duct 334 formed in the rotating airfoil 310, such as... Figure 8 As shown. Each opening 332 is configured to eject air from an air source as jet air from the suction surface 326 in an outward direction. The outline depicts the airflow on the suction surface 326 and the pressure surface 328. When air is ejected from the opening 332, the ejected air disrupts the following air above the surface. For example, as... Figure 8 As shown, the ejected air disrupts the airflow on the intake surface 326, and more specifically, disrupts the boundary layer, reducing the lift generated by the rotating airfoil 310. Alternatively, air can be drawn into the opening 332 instead of ejected from it. When the opening 332 is located on the suction surface 326, as... Figure 8 As shown, drawing air into the opening 332 can have the opposite effect to jetting air and increase the lift generated by the rotating airfoil 310.

[0040] The opening 332 includes edges, and the edges define the plane of the opening 332. These edges, and therefore the opening 332, can have any suitable shape in the surface they form (e.g., Figure 7 (Suction surface 326 in the middle). Figure 7 In this design, the opening is shown as a circular opening. Other suitable shapes include, for example, elliptical openings, parabolic openings, rectangular openings, and triangular openings. Furthermore, the opening 332 can have various suitable shapes (perpendicular to the plane of the opening 332) within the rotating airfoil 310. The channel connecting the opening 332 and the conduit 334 can be, for example, cylindrical or conical. Additionally, the opening 332 can have a wide range of suitable sizes. The opening 332 can be large, for example, with an area of ​​2 square centimeters, or small, for example, with an area of ​​6 square micrometers. When multiple smaller openings 332 are used, the multiple openings 332 can be arranged on the surface of the rotating airfoil 310 (e.g., suction surface 326).

[0041] exist Figure 8 In the illustrated embodiment, the injected air is ejected directly outward in a direction perpendicular to the plane of opening 332. The ejected air may be directed in other directions instead of directly outward. Figure 9A and 9B This is a top view of the rotating airfoil 310, each airfoil having an optional orientation of the opening 332. Figure 9AThe opening 332 shown is configured to eject air outward and toward the leading edge 312 (air jetting). This is in the opposite direction to the direction in which the boundary layer flows over the suction surface 326. Figure 9B The opening 332 shown is configured to eject air outwards and toward the trailing edge 314 (air jetting). This is consistent with the boundary layer flow direction along the suction surface 326. In the example discussed above, the opening 332 is shown as being formed on the suction surface 326, but the opening 332 could be formed on the pressure surface 328 instead of the suction surface 326, as... Figure 9C As shown. Figure 9C This is a top view of a rotating airfoil 310 having an opening 332 formed on the pressure surface 328. When the opening 332 is located on the pressure surface 328, as... Figure 9C As shown, air ejected from the opening 332 increases the lift generated by the rotating airfoil 310, while air drawn into the opening 332 reduces the lift generated by the rotating airfoil 310.

[0042] The opening 332 can be formed anywhere on the suction surface 326 or the pressure surface 328. In some embodiments, such as Figure 7 As shown, the opening 332 is formed closer to the tip 318 than the root 316, and can be formed on the outer half of the rotating airfoil 310 in the radial direction R. The opening 332 can also be formed closer to the leading edge 312 than the trailing edge 314, for example on the front half of the suction surface 326 or the pressure surface 328.

[0043] Figure 10 A rotary airfoil assembly 300 including a rotary airfoil 310 is shown according to one embodiment. Figure 10 The rotating airfoil assembly 300 shown is Figure 2 The rotating part 160 of the single-fan motor 100 in the duct, and Figure 10 It is along Figure 2 A schematic cross-sectional view taken by line 10-10 in the diagram. The rotating airfoil 310 (fan blade 162) of the rotating airfoil assembly 300 is shown in... Figure 10 The rotating airfoil 310 rotates clockwise around the rotation axis 301 (rotation axis 161). For the convenience of the following discussion, the angular positions of the rotating airfoil 310 and the rotating airfoil assembly 300 are given relative to the rotation axis 301, as shown below. Figure 10 As shown. Therefore, the rotating airfoil 310 rotates from zero degrees to 180 degrees in the downward direction and from 180 degrees to 360 degrees (zero degrees) in the upward direction.

[0044] Figure 10 The rotation axis 301 is shown to be at an angle (e.g., pitching up or down) relative to the airflow entering the rotating airfoil 310. More specifically, in Figure 10In this configuration, the rotation axis 301 is pitched upwards relative to the airflow entering the rotating airfoil 310, for example, when the aircraft 10 (and the longitudinal centerline 101 of the ductless single-fan engine 100) pitches upwards during takeoff or climb. In this case, the rotating airfoil assembly 300 is subjected to a non-axial component of the upward airflow. The lift generated by each rotating airfoil 310 at the top (zero degrees) and bottom (180 degrees) of rotation is similar to the lift generated by the rotating airfoil 310 if the rotating airfoil assembly 300 is not tilted. However, each rotating airfoil 310 generates less lift as it moves downwards from the top (zero degrees) to the bottom (180 degrees), and more lift as it moves upwards from the bottom (180 degrees) to the top (zero degrees). This variation in lift is caused by… Figure 10 The larger dashed line schematically illustrates this. When the rotating airfoil 310 rotates once, the minimum lift generated by the rotating airfoil 310 is 90 degrees. As the rotating airfoil 310 continues to rotate, the lift steadily increases from this point to 270 degrees, and then steadily decreases. This can be referred to as the 1P load.

[0045] The lift variation during one rotation (1P) causes the rotating airfoil 310 to experience cyclic stress. These cyclic stresses must be considered when designing the rotating airfoil 310 to avoid fatigue. In the embodiment discussed here, the opening 332 can be used to mitigate the magnitude of the lift difference, or even eliminate it entirely. Figure 10 In the state shown, air can selectively flow from the suction surface 326 formed in each rotating airfoil 310. Figure 8 (as shown in the diagram) or pressure surface 328 ( Figure 9C An opening 332 in one of the structures shown ejects air to disrupt the airflow on the suction surface 326 or the pressure surface 328. For example, the opening 332 may be formed on the suction surface 326, and as the rotating airfoil 310 travels upward from the bottom (180 degrees) to the top (0 degrees), air can be ejected, reducing the lift of the rotating airfoil 310 as it travels upward and the magnitude of the cyclic load on the rotating airfoil 310. The amount of air ejected from each opening 332 can be varied as the rotating airfoil 310 rotates upward. As described above, maximum lift is generated when the rotating airfoil 310 is at the 270-degree position, and therefore, the amount of air ejected from the opening 332 can increase from the bottom (180 degrees) to the 270-degree position and then decrease from the 270-degree position to the top (0 degrees). Figure 10 In the diagram, the change in the amount of air ejected is indicated by the length of the arrow in duct 334.

[0046] Conversely, opening 332 can be formed on pressure surface 328, and air can be ejected as the rotating airfoil 310 travels downward from the top (zero degrees) to the bottom (180 degrees). As the rotating airfoil 310 travels downward, lift increases, but the magnitude of the cyclic load on the rotating airfoil 310 decreases. As described above, the lift generated is minimal when the rotating airfoil 310 is at the 90-degree position; therefore, the angle at which the air expelled from opening 332 can increase lift from the top (zero degrees) to 90 degrees, and then decrease from 90 degrees to the bottom (180 degrees).

[0047] exist Figure 10 In the illustrated embodiment, the selective ejection of air from the opening 332 is done passively without the use of valves, controllers, etc. In this embodiment, each rotating airfoil 310 is part of a corresponding pair of rotating airfoils 310. A first rotating airfoil 310a is positioned opposite a second rotating airfoil 310b, with a rotation axis 301 located between them. More specifically, the first rotating airfoil 310a and the second rotating airfoil 310b are spaced 180 degrees apart, such that the first rotating airfoil 310a and the second rotating airfoil 310b are directly opposite each other. The first rotating airfoil 310a and the second rotating airfoil 310b together form a pair of rotating airfoils 310. The conduit 334 of the first rotating airfoil 310a is fluidly connected to the conduit 334 of the second rotating airfoil 310b, and in this embodiment, they are directly fluidly connected to each other, thereby forming a single flow channel 336 between the opening 332 on the first rotating airfoil 310a and the opening 332 on the second rotating airfoil 310b. When each rotating airfoil 310 includes a plurality of openings 332, each of the plurality of openings 332 can be connected to a corresponding conduit 334 (see Figure 7 Each conduit 334 on the first rotating airfoil 310a can be fluidly connected to a corresponding conduit 334, and thus, a corresponding opening 332 on the second rotating airfoil 310b. In such an embodiment, a plurality of flow channels 336 are formed between the first rotating airfoil 310a and the second rotating airfoil 310b. In other embodiments, a plurality of openings 332 may be connected to a single conduit 334.

[0048] In a non-axial flow state, a pressure difference will also be generated between the opening 332 on the first rotating airfoil 310a and the opening 332 on the second rotating airfoil 310b. Figure 10 In the illustrated embodiment, an opening 332 is formed on the suction surface 326, and the pressure difference is inversely proportional to the lift difference. This pressure change is caused by... Figure 10The smaller dashed lines schematically illustrate this. The pressure difference between the openings 332 on the first rotating airfoil 310a and the second rotating airfoil 310b drives air to flow through the flow channel 336 from the opening 332 on the second rotating airfoil 310b to the opening 332 on the first rotating airfoil 310a. This causes air to be ejected from the opening 332 on the rotating airfoil 310a, disrupting the airflow through the suction surface 326 and reducing the lift generated by the first rotating airfoil 310a. Since this airflow is driven by the pressure difference, therefore... Figure 10 The embodiment shown passively adjusts to different angles of the rotation axis 301 and provides an increase or decrease in the amount of air ejected from the opening 332 as the rotating airfoil 310 travels from the bottom (180 degrees) to the top (zero degrees).

[0049] Figure 11 A rotary airfoil assembly 300 including a rotary airfoil 310 is shown according to another embodiment. (See also...) Figure 10 In the arrangement shown, Figure 11 The state in which the rotation axis 301 is angled (e.g., pitched up or down) relative to the airflow entering the rotating airfoil 310 is shown. Figure 11 The rotating airfoil assembly 300 shown is... Figure 10 The rotating airfoil assembly 300 shown is the same, but the conduit 334 of the first rotating airfoil 310a and the conduit 334 of the second rotating airfoil 310b form a single flow channel 336, and each conduit 334 is fluidly connected to the central manifold 338. Figure 11 The rotating airfoil assembly 300 shown can be coupled with Figure 10 The rotating airfoil assembly 300 shown operates in a basically similar manner.

[0050] Figure 12 A rotary airfoil assembly 300 including a rotary airfoil 310 is shown according to yet another embodiment. (See also...) Figure 10 and 11 In the arrangement shown, Figure 12 This illustrates a state where the rotation axis 301 is at an angle (e.g., tilted upwards or downwards) relative to the airflow entering the rotating airfoil 310. Figure 10 and 11 In the illustrated embodiment, the air ejected from opening 332 (including the amount of ejected air) is passively controlled by pressure differential. The ejection of air from opening 332 can be actively controlled. Figure 12In the illustrated embodiment, each duct 334 is fluidly connected to the central manifold 338 via a flow control valve 342 located between the central manifold 338 and the opening 332. Air is supplied to the central manifold 338 from an air source 344. Suitable air sources 344 include, for example, engine sources, such as compressor cooling from a compressor-cooled air (CCA) system 154. The flow control valve 342 is configured to selectively control the airflow from the central manifold 338 to the opening 332 to disrupt the airflow across the suction surface 326 or the pressure surface 328 in the manner described above.

[0051] In this embodiment, the flow control valve 342 can be operated by a controller, such as the engine controller 170 (see also...). Figure 2 Other suitable controllers may be used, including, for example, a dedicated controller or a controller (flight controller) that is part of the flight control system of aircraft 10. In this embodiment, controller 170 is a computing device having one or more processors 172 and one or more memories 174. Processor 172 may be any suitable processing device, including but not limited to microprocessors, microcontrollers, integrated circuits, logic devices, programmable logic controllers (PLCs), application-specific integrated circuits (ASICs), and / or field-programmable gate arrays (FPGAs). Memory 174 may include one or more computer-readable media, including but not limited to non-transitory computer-readable media, computer-readable non-volatile media (e.g., flash memory), RAM, ROM, hard drives, flash drives, and / or other storage devices.

[0052] Memory 174 may store information accessible to processor 172, including computer-readable instructions executable by processor 172. Instructions may be any set or sequence of instructions that, when executed by processor 172, cause processor 172 and controller 170 to perform operations. In some embodiments, instructions may be executed by processor 172 to cause processor 172 to perform any operations and functions for which controller 170 is constructed, as will be further described below. Instructions may be software written in any suitable programming language or may be implemented in hardware. Furthermore, and / or alternatively, instructions may be executed on processor 172 in logically and / or virtually separate threads. Memory 174 may further store data accessible by processor 172.

[0053] The techniques discussed herein refer to computer-based systems and the actions taken by and from computer-based systems, as well as the information sent to and from computer-based systems. Those skilled in the art will recognize that the inherent flexibility of computer-based systems allows for a wide variety of possible configurations, combinations, and divisions of tasks and functions among components. For example, the processes discussed herein can be implemented using a single computing device or multiple computing devices working in combination. Databases, memory, instructions, and applications can be implemented on a single system or distributed across multiple systems. Distributed components can operate sequentially or in parallel.

[0054] The controller 170 is operatively and communicatively coupled to each flow control valve 342 and configured to selectively control the airflow from the central manifold 338 to the opening 332 by, for example, operating each flow control valve 342 to supply a desired amount of air from the central manifold 338 to each opening 332. The controller 170 may also be operatively and communicatively coupled to suitable devices, such as pumps or other valves, to supply air at a desired pressure from the air source 344 to the central manifold 338.

[0055] The controller 170 is configured to receive an indication (or signal) that the rotation axis 301 of the rotating airfoil 310 is angled upwards or downwards.

[0056] Upon receiving this signal, the airflow from the central manifold 338 to the opening 332 is selectively controlled. This indication can be received from a sensor configured to detect the aircraft's pitch, for example, directly from the sensor or from another source such as the flight controller.

[0057] Source reception.

[0058] Figure 10-12 Each of these depicts a state in which an upward component of a non-axial flow enters the rotating airfoil 310, for example, when the rotation axis 301 is angled upwards during takeoff or climb of the aircraft 10. When a downward component of a non-axial flow exists...

[0059] When the component enters the rotating airfoil 310, for example when the rotation axis 301 is angled downwards during the descent of the aircraft 10, the zero-asymmetric load state is reversed. Therefore, when the rotation axis 301 is angled downwards, selective loading occurs from each opening 332.

[0060] The ejected air is the opposite of the above conditions.

[0061] Other aspects of this disclosure are provided by the subject matter of the following clauses.

[0062] A rotating airfoil assembly includes a rotation axis and a plurality of rotating airfoils configured to rotate about the rotation axis.

[0063] Each airfoil in a rotating airfoil includes a leading edge, a trailing edge, an suction surface between the leading and trailing edges, and a pressure surface between the leading and trailing edges. The suction and pressure surfaces are positioned on opposite sides of the airfoil so that when air flows with the rotating airfoil...

[0064] As the airfoil rotates around its axis of rotation and flows over the suction and pressure surfaces of the airfoil, it generates lift. At least one opening is located on either the suction or pressure surface. At least one opening is configured to either expel air or draw air into the opening.

[0065] The rotating airfoil assembly according to the foregoing clause includes a plurality of openings on one of the suction or pressure surfaces. Each of the plurality of openings is configured to either exhaust air or draw air into the opening.

[0066] The rotating airfoil assembly according to any one of the preceding clauses, wherein at least one opening is closer to the leading edge than the trailing edge.

[0067] The rotary airfoil assembly according to any one of the preceding clauses, wherein each rotary airfoil comprises a root and a tip. At least one opening is closer to the tip than the root.

[0068] The rotating airfoil assembly according to any one of the preceding clauses, wherein the opening includes an edge and the edge defines a plane of the opening 5. The opening is configured to eject air outward from one of the suction surface or the pressure surface in a direction perpendicular to the opening plane.

[0069] The rotating airfoil assembly according to any one of the preceding clauses, wherein the opening is configured to eject air outward from one of the suction or pressure surfaces in an outward and leading-edge direction.

[0070] The rotating airfoil assembly according to any one of the preceding clauses, wherein the opening is configured to eject air outward from one of the suction or pressure surfaces in an outward and trailing-edge direction.

[0071] The rotating airfoil assembly according to any one of the preceding clauses, wherein at least one opening is located on the suction surface. When the rotating airfoil rotates in the upward direction and when the axis of rotation is angled upward relative to the airflow flowing into the rotating airfoil assembly, the opening is configured to selectively eject air to disturb the air flowing above the suction surface.

[0072] The rotary airfoil assembly according to any one of the preceding clauses, wherein one of the plurality of rotary airfoils is a first rotary airfoil and another of the plurality of rotary airfoils is a second rotary airfoil. The opening of the first rotary airfoil and the opening of the second rotary airfoil are fluidly connected to each other via conduits.

[0073] The rotating airfoil assembly according to any one of the preceding clauses, wherein the first rotating airfoil is positioned opposite the second rotating airfoil, and the axis of rotation is located therebetween.

[0074] The rotating airfoil assembly according to any one of the preceding clauses, wherein at least one opening of each first rotating airfoil and the opening of the second rotating airfoil are located on their respective suction surfaces. Air (a) is drawn into the opening of the second rotating airfoil, (b) travels from the opening of the second rotating airfoil through a duct to the opening of the first rotating airfoil, and (c) is ejected from the opening of the second rotating airfoil when (i) the first rotating airfoil rotates in an upward direction, (ii) the second rotating airfoil rotates in a downward direction, and (iii) the axis of rotation is angled upward relative to the airflow flowing into the rotating airfoil assembly, thereby disturbing the air flowing across the suction surface of the first rotating airfoil.

[0075] The rotating airfoil assembly according to any one of the preceding clauses further includes a manifold. The opening of each rotating airfoil is fluidly connected to the manifold.

[0076] The rotating airfoil assembly according to any one of the preceding clauses further includes an air source fluidly connected to the manifold and configured to supply air to the manifold.

[0077] The rotating airfoil assembly according to any one of the preceding clauses, wherein the opening of each rotating airfoil is fluidly connected to a manifold via a conduit. A flow control valve is located in the conduit and configured to control the flow rate of air from the manifold to the opening.

[0078] The rotating airfoil assembly according to any one of the preceding clauses further includes a controller operably coupled to each flow control valve and configured to selectively operate each flow control valve to supply a desired amount of air from the manifold to each opening.

[0079] According to any one of the preceding clauses, a rotating airfoil assembly, wherein at least one opening is located on the suction surface, and wherein a controller is configured to (i) receive an indication that the axis of rotation of the rotating airfoil assembly is angled upward or downward relative to the direction of airflow flowing into the rotating airfoil assembly, (ii) in response to the indication that the axis of rotation of the rotating airfoil assembly is angled upward, operate the flow control valve to supply air to the opening in each rotating airfoil rotating in the upward direction, and (iii) in response to the indication that the axis of rotation of the rotating airfoil assembly is angled downward, operate the flow control valve to supply air to the opening in each rotating airfoil rotating in the downward direction.

[0080] An engine includes a rotary airfoil assembly according to any of the preceding claims, and a torque generating system coupled to the rotary airfoil assembly and configured to rotate the rotary airfoil assembly about a rotation axis of the rotary airfoil assembly.

[0081] The engine according to any one of the preceding clauses, wherein the engine is a pipeless single-fan engine, the torque generation system is a turbine of a gas turbine engine, and the rotating airfoil assembly is a fan, each of the plurality of rotating airfoils being a fan blade.

[0082] An engine according to any one of the preceding clauses, wherein the engine is a turboprop engine, the torque generation system is a turbine of a gas turbine engine, the rotating airfoil assembly is a propeller assembly, and each of the plurality of rotating airfoils is a propeller.

[0083] The engine according to any one of the preceding clauses further includes a manifold, an air source, and a controller. An opening of each rotating airfoil is fluidly connected to the manifold. The air source is fluidly connected to the manifold and configured to supply air to the manifold. The air source is an engine air source from the torque generation system. The controller is operatively connected to each flow control valve and configured to selectively operate each flow control valve to supply a desired amount of air from the manifold to each opening.

[0084] While the foregoing description pertains to preferred embodiments, it should be noted that other variations and modifications will be apparent to those skilled in the art and can be made without departing from the spirit or scope of this disclosure. Furthermore, the features described in relation to one embodiment may be used in conjunction with other embodiments, even if not explicitly stated above.

Claims

1. A rotating airfoil component assembly, characterized in that, include: axis of rotation; A plurality of rotating airfoils are configured to rotate about a rotation axis. Each rotating airfoil includes a leading edge, a trailing edge, an suction surface between the leading edge and the trailing edge, and a pressure surface between the leading edge and the trailing edge. The suction surface and the pressure surface are located on opposite sides of the rotating airfoil, such that the rotating airfoil generates lift when airflow flows over the suction surface and the pressure surface of the rotating airfoil as it rotates about the rotation axis. and At least one opening, said at least one opening on one of the suction surface or the pressure surface, said at least one opening being configured to eject air or draw air into said at least one opening; In the plurality of rotating airfoils, one of the rotating airfoils is a first rotating airfoil, and the other of the plurality of rotating airfoils is a second rotating airfoil. The at least one opening of the first rotating airfoil and the at least one opening of the second rotating airfoil are fluidly connected to each other via a conduit. The first rotating airfoil is positioned opposite the second rotating airfoil, and the axis of rotation is located therebetween. Wherein the at least one opening of the first rotating airfoil and the at least one opening of the second rotating airfoil are located on the corresponding suction surface, air (a) is drawn into the at least one opening of the second rotating airfoil, (b) travels from the at least one opening of the second rotating airfoil through the duct to the at least one opening of the first rotating airfoil, and (c) when (i) the first rotating airfoil rotates in an upward direction, (ii) the second rotating airfoil rotates in a downward direction and (iii) the axis of rotation is angled upward relative to the airflow flowing into the rotating airfoil assembly, it is ejected from the at least one opening of the first rotating airfoil, disturbing the air flowing across the suction surface of the first rotating airfoil.

2. The rotating airfoil assembly according to claim 1, characterized in that, It further includes a plurality of openings on one of the suction surface or the pressure surface, each of the plurality of openings being configured to eject air or draw air into the opening.

3. The rotating airfoil assembly according to claim 1, characterized in that, The at least one of the openings is closer to the leading edge than to the trailing edge.

4. The rotating airfoil assembly according to claim 1, characterized in that, Each of the rotating airfoils includes a root and a tip, and the at least one opening is closer to the tip than to the root.

5. The rotating airfoil assembly according to claim 1, characterized in that, in, For each rotating airfoil, the at least one opening includes an edge and the edge defines a plane of the corresponding opening, each opening being configured to eject air outward from one of the suction surface or the pressure surface in a direction perpendicular to the plane of the corresponding opening.

6. The rotating airfoil assembly according to claim 1, characterized in that, in, For each rotating airfoil, the at least one opening is configured to eject air outward from one of the suction surface or the pressure surface in an outward direction toward the leading edge.

7. The rotating airfoil assembly according to claim 1, characterized in that, in, For each rotating airfoil, the at least one opening is configured to eject air outward from one of the suction surface or the pressure surface in an outward direction toward the trailing edge.

8. The rotating airfoil assembly according to claim 1, characterized in that, The at least one opening is located on the suction surface, and the at least one opening is configured to selectively eject air to disturb the air flowing over the suction surface when the rotating airfoil rotates in an upward direction and when the axis of rotation is angled upward relative to the airflow flowing into the rotating airfoil assembly.

9. The rotating airfoil assembly according to claim 1, characterized in that, It further includes a manifold, wherein at least one opening of each of the rotating airfoils is fluidly connected to the manifold.

10. The rotating airfoil assembly according to claim 9, characterized in that, It further includes an air source, which is fluidly connected to the manifold and configured to supply air to the manifold.

11. The rotating airfoil assembly according to claim 10, characterized in that, In the case of the at least one opening of each of the rotating airfoils, the airfoil is fluidly connected to the manifold via a conduit, and a flow control valve is located in the conduit and configured to control the flow of air from the manifold to the at least one opening.

12. The rotating airfoil assembly according to claim 11, characterized in that, It further includes a controller operably coupled to each flow control valve and configured to selectively operate each flow control valve to supply a desired amount of air from the manifold to each opening.

13. The rotating airfoil assembly according to claim 12, characterized in that, The at least one opening is located on the suction surface, and The controller is configured to (i) receive an indication that the axis of rotation of the rotating airfoil assembly is angled upward or downward relative to the direction of airflow entering the rotating airfoil assembly, (ii) in response to the indication that the axis of rotation of the rotating airfoil assembly is angled upward, operate the flow control valve to supply air to at least one opening in each rotating airfoil rotating in the upward direction, and (iii) in response to the indication that the axis of rotation of the rotating airfoil assembly is angled downward, operate the flow control valve to supply air to at least one opening in each rotating airfoil rotating in the downward direction.

14. An engine, characterized in that, include: The rotating airfoil assembly according to claim 1; and A torque generating system is coupled to the rotating airfoil assembly and configured to rotate the rotating airfoil assembly about its axis of rotation.

15. The engine according to claim 14, characterized in that, The engine is a pipeless single-fan engine, the torque generation system is a gas turbine engine turbine, the rotating airfoil assembly is a fan, and each of the plurality of rotating airfoils is a fan blade.

16. The engine according to claim 14, characterized in that, The engine is a turboprop engine, the torque generation system is a gas turbine engine turbine, the rotating airfoil assembly is a propeller assembly, and each of the plurality of rotating airfoils is a propeller.

17. The engine according to claim 14, characterized in that, Further includes: A manifold, wherein at least one opening of each of the rotating airfoils is fluidly connected to the manifold; An air source, which is fluidly connected to the manifold and configured to supply air to the manifold, wherein the air source is an engine air source from the torque generation system; and A controller, operably coupled to each flow control valve and configured to selectively operate each flow control valve to supply a desired amount of air from the manifold to each opening.

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