Aircraft

Abstract

To expand an employment range of fan devices and improve the propulsion efficiency of an aircraft, by suppressing separation of an air flow inside a housing.SOLUTION: An aircraft comprises an airframe body, a tail unit, main wings, and fan devices. The fan devices mounted to an exterior surface of the airframe body comprise: a rotor shaft, moving blades, a housing, stator blades, and stator blade fluid suction parts. The rotor shaft is arranged outside of the exterior surface of the airframe body in an airframe radial direction. The moving blades are provided outside in a rotor radial direction with the rotor shaft as a center, relative to the rotor shaft. The housing extends in a forward and rearward direction, and has a respective opening in the front and in the rear in the forward and rearward direction. The housing is provided so as to cover the rotor shaft and the moving blades. The stator blades extend inward in the rotor radial direction from an inner peripheral surface of the housing. The stator blade fluid suction parts suction fluid from gaps between stator blade tip portions on the inside of the stator blades in the rotor radial direction and the rotor shaft.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to aircraft. [Background technology]

[0002] For example, Patent Document 1 discloses an aircraft equipped with a BLI (Boundary layer injection) fan. The BLI fan in Patent Document 1 is disposed at a position rearward of the main wing and propulsion engine of the aircraft. The BLI fan includes a cylindrical nacelle provided on the radially outer side of the aircraft body, and a fan that can rotate between the nacelle and the aircraft body. The BLI fan generates an airflow by rotating the fan between the nacelle and the aircraft body, and the boundary layer formed on the surface of the aircraft body is sucked into the nacelle by the airflow. The BLI fan obtains thrust by blowing the airflow from inside the nacelle backward in the propulsion direction of the aircraft. In this way, the BLI fan increases the propulsion efficiency of the aircraft by taking in air from the boundary layer and obtaining thrust. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] US Patent Application Publication No. 2018 / 0208297 Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, the BLI fan described above is usually provided outside the outer surface of the aircraft. In this case, the rotor blades of the BLI fan rotate around a rotor shaft that is disposed outside the outer surface of the aircraft. In a BLI fan configured as described above, the air flow inside the housing of the BLI fan is more affected by the boundary layer formed on the outer surface of the aircraft in a region closer to the outer surface of the aircraft than the rotor shaft, compared to a region farther from the outer surface of the aircraft than the rotor shaft. Therefore, the air flow speed is reduced on the side closer to the outer surface of the aircraft than the rotor shaft. As a result, in the housing of the BLI fan, a distribution of the inflow angle of the air flow with respect to the rotor blade occurs in the radial and circumferential directions of the housing. In addition, in a region where the air flow speed is slow, separation is likely to occur on the blade surface of the rotor blade, and therefore stall is likely to occur near the tip of the stator blade located on the radial inside of the stator blade disposed downstream of the rotor blade. On the other hand, if the operation of the BLI fan is stopped in areas where stalls are likely to occur in order to avoid such stalls, the operating range of the BLI fan will be narrowed, making it difficult to further improve the propulsion efficiency of aircraft using the BLI fan.

[0005] The present disclosure has been made to solve the above-mentioned problems, and aims to provide an aircraft that can expand the operating range of the fan unit and further improve propulsion efficiency by suppressing separation of the air flow within the housing. [Means for solving the problem]

[0006] In order to solve the above problems, an aircraft according to the present disclosure includes an aircraft body, a tail, a main wing, and a fan unit. The aircraft body extends in a longitudinal direction. The tail is provided at the rear of the aircraft body. The main wing is provided on the aircraft body forward of the tail in the longitudinal direction. The fan unit is provided on an outer surface of the aircraft body. The fan unit includes a rotor shaft, a rotor blade, a housing, a stator blade, and a stator blade fluid suction unit. The rotor shaft is disposed outward in the aircraft radial direction from the outer surface of the aircraft body. The rotor shaft is provided rotatably about a central axis extending in the longitudinal direction. The rotor blade is provided outward in the rotor radial direction with respect to the rotor shaft as the center. The housing is fixed to the aircraft body. The housing extends in the longitudinal direction and has openings at the front and rear of the longitudinal direction. The housing is provided to cover the rotor shaft and the rotor blade. The stator vane extends inward in a radial direction of the rotor from an inner circumferential surface of the housing. The stator vane fluid suction portion suctions fluid at a stator vane tip side on the inner side in the radial direction of the rotor of the stator vane.

[0007] The aircraft according to the present disclosure includes an aircraft body, a tail, a main wing, and a fan unit. The aircraft body extends in a longitudinal direction. The tail is provided at the rear of the aircraft body. The main wing is provided on the aircraft body forward of the tail in the longitudinal direction. The fan unit is provided on an outer surface of the aircraft body. The fan unit includes a rotor shaft, a rotor blade, a housing, a stator blade, and a rotor blade fluid suction unit. The rotor shaft is disposed radially outward of the outer surface of the aircraft body. The rotor shaft is provided rotatably about a central axis extending in the longitudinal direction. The rotor blade is provided radially outward of the rotor shaft with the rotor shaft as the center. The housing is fixed to the aircraft body. The housing extends in the longitudinal direction and has openings at the front and rear of the longitudinal direction. The housing is provided to cover the rotor shaft and the rotor blade. The stationary blade extends inward in a radial direction of the rotor from an inner circumferential surface of the housing. The rotor blade fluid suction portion sucks the fluid within the housing on an outer side of the rotor blade in the radial direction of the rotor. Effect of the Invention

[0008] According to the aircraft disclosed herein, by suppressing separation of the air flow within the housing, the operating range of the fan device can be expanded and propulsion efficiency can be improved. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a side view of an aircraft according to an embodiment of the present disclosure. [Diagram 2] FIG. 2 is a cross-sectional view of a sensor device provided on an aircraft according to the first embodiment of the present disclosure. [Diagram 3] FIG. 11 is a cross-sectional view of a sensor device provided on an aircraft according to a second embodiment of the present disclosure. [Figure 4] FIG. 11 is a cross-sectional view of a sensor device installed in an aircraft according to a third embodiment of the present disclosure. [Diagram 5]FIG. 11 is a cross-sectional view of a sensor device provided on an aircraft according to a fourth embodiment of the present disclosure. [Figure 6] FIG. 13 is a functional block diagram of a control device provided in an aircraft according to a fourth embodiment of the present disclosure. [Figure 7] 10 is a flowchart showing the procedure of a fan device control method according to a fourth embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] First Embodiment (Aircraft configuration) Hereinafter, an aircraft according to an embodiment of the present disclosure will be described with reference to FIGS. As shown in FIG. 1, an aircraft 1 includes at least an aircraft body 2, a tail unit 4, a main wing 3, and a fan unit 10A.

[0011] The main body 2 extends in a front-to-rear direction Da connecting a nose 2a and a tail (rear portion) 2b. The empennage 4 is provided at the tail 2b of the main body 2.

[0012] The tail 4 includes a vertical tail 4a and a pair of horizontal tails (not shown). The vertical tail 4a extends upward in the vertical direction Dv from the tail 2b of the aircraft body 2. The horizontal tails (not shown) extend, for example, from the tail 2b of the aircraft body 2 on both sides in a width direction (direction perpendicular to the paper surface of FIG. 1) perpendicular to the longitudinal direction Da and the vertical direction Dv. The horizontal tails (not shown) may extend, for example, from the upper end of the vertical tail 4a on both sides in the width direction.

[0013] The main wing 3 is provided on the aircraft body 2, further forward in the fore-and-aft direction Da (closer to the nose 2a) than the tail 4. The main wing 3 is provided between the nose 2a and tail 2b of the aircraft body 2. The main wing 3 extends on both sides in the width direction from the aircraft body 2. The aircraft 1 is also equipped with a propulsion unit (not shown), such as a motor or a jet engine.

[0014] (Fan unit configuration) The fan unit 10A is provided on the outside of the aircraft body 2 in the aircraft radial direction Dp. The fan unit 10A is provided on the outer surface 2f of the tail 2b of the aircraft body 2. A plurality of fan units 10A are provided at intervals in the aircraft circumferential direction Dc along the outer surface 2f of the aircraft body 2. As shown in Fig. 2, each fan unit 10A includes a rotor shaft 11, a rotor blade 12, a housing 13, a stator blade 14, and a fluid suction unit 20A.

[0015] The rotor shaft 11 is disposed outside (upper in FIG. 2) the outer surface 2f of the aircraft body 2 in the aircraft radial direction Dp. The rotor shaft 11 is rotatably provided around a central axis Cf extending in the front-rear direction Da via a bearing (not shown). The rotor shaft 11 is driven to rotate around the central axis Cf by a motor (not shown) or the like.

[0016] The rotor blades 12 are provided on the outside of the rotor shaft 11 in a fan radial direction (rotor radial direction) Df centered on the rotor shaft 11. The rotor blades 12 are provided so as to extend from the rotor shaft 11 outward in the fan radial direction Df. A plurality of the rotor blades 12 are provided at intervals in the fan circumferential direction (rotor circumferential direction) Ds around the rotor shaft 11. The plurality of rotor blades 12 rotate integrally with the rotor shaft 11 around the central axis Cf.

[0017] The housing 13 is fixed to the aircraft body 2. The housing 13 extends in the front-to-rear direction Da and has an opening 15 at the front in the front-to-rear direction Da and an opening 16 at the rear. The housing 13 is provided so as to cover the rotor shaft 11 and the rotor blades 12. Gas flows into the housing 13 from the opening 15 at the front in the front-to-rear direction Da. The gas that has flowed into the housing 13 is discharged to the outside of the fan unit 10A from the opening 16 at the rear.

[0018] The stator vanes 14 extend inward in the fan radial direction Df from the inner circumferential surface 13f of the housing 13. A plurality of the stator vanes 14 are provided at intervals in the fan circumferential direction Ds. The plurality of stator vanes 14 are arranged at intervals in the front-rear direction Da rearward of the plurality of rotor blades 12. Each stator vane 14 is arranged on one side in the fan circumferential direction Ds, around the central axis Cf via the plurality of rotor blades 12. Each stator vane 14 has a pressure side surface 14a that receives the swirling airflow. Each stator vane 14 has a suction side surface 14b opposite to the pressure side surface 14a on the other side in the fan circumferential direction Ds. Note that, although the inner peripheral tip of the stator vane 14 is depicted in Fig. 2 as a cantilever stator vane having a certain gap with the rotor shaft 11, there is no problem if a shroud structure in which a recessed portion is provided in the rotor shaft 11 is used.

[0019] (Configuration of fluid suction part) The fluid suction section 20A sucks in a portion of the gas (fluid) flowing within the housing 13 in order to reduce the influence of a boundary layer generated within the housing 13. The fluid suction section 20A of the present embodiment includes a stator vane fluid suction section 21A and an on-off valve 30.

[0020] The stator vane fluid suction portion 21A sucks in fluid on the side of the stator vane tip portion 14t on the inside in the fan radial direction Df of the stator vane 14. A plurality of the stator vane fluid suction portions 21A are provided at intervals in the fan circumferential direction Ds around the rotor shaft 11. Each of the stator vane fluid suction portions 21A has a first opening 22A, a second opening 23, and a first flow path portion 24.

[0021] The first opening 22A opens at the stator vane tip 14t of each stator vane 14. In this embodiment, the first opening 22A is slit-shaped and opens at the stator vane tip 14t to the suction surface 14b of the stator vane 14, which is the low-pressure side when the fan device 10A is in operation. The height Ha of the first opening 22A in the fan radial direction Df is preferably about 0.2 times the height Hs of the stator vane 14 in the fan radial direction Df. This allows air to be sucked in from the vicinity of the stator vane tip 14t, which is the starting point when stall occurs in the air flow in the stator vane 14.

[0022] The position of the first opening 22A in the longitudinal direction Da may be rearward (downstream) of the intermediate position 14c between the leading edge 14f and the trailing edge 14r of the stator blade 14 at the stator blade tip 14t in the longitudinal direction Da. By positioning the first opening 22A in such a position in the longitudinal direction Da, the boundary layer near the separation starting point at the stator blade tip 14t can be efficiently sucked in. In addition, in order to maintain the blade surface shape at the suction side surface 14b of the stator blade 14, the width Wa of the first opening 22A in the longitudinal direction Da may be 0.1 times or less the length Ls of the stator blade tip 14t in the longitudinal direction Da.

[0023] The second opening 23 opens rearward from the first opening 22A in the front-rear direction Da. The second opening 23 opens further rearward from the fan unit 10A. The second opening 23 can be provided, for example, at the rear of the housing 13, at the tail 2b of the aircraft main body 2. The second opening 23 of this embodiment opens rearward in the front-rear direction Da. The opening position of the second opening 23 is not limited to the rear of the fan unit 10A, and may be located, for example, on the outer periphery of the housing 13.

[0024] The first flow passage 24 communicates the first opening 22A and the second opening 23. The first flow passage 24 is provided in the housing 13 or the airframe body 2. The rear of the second opening 23 becomes a negative pressure area when the aircraft 1 is flying. On the other hand, upstream of the stator blade 14, the total pressure increases by the pressure ratio of the rotor blade due to the compression effect of the rotor blade 12, and the static pressure on the blade surface of the stator blade 14 also becomes higher than the pressure behind the fan. As a result, the fluid (air) constituting the boundary layer flowing in the housing 13 is sucked from the first opening 22A from the area near the stator blade tip 14t including the gap between the stator blade tip 14t and the rotor shaft 11. The fluid sucked in by the first opening 22A is discharged rearward from the second opening 23 via the first flow passage 24. The flow rate of the sucked in fluid is assumed to be about 1% of the mainstream, and it is necessary to determine the width Wa and length Ls so as to satisfy the assumed suction flow rate.

[0025] The on-off valve 30 turns on and off the suction of the fluid in each stator vane fluid suction section 21A. The on-off valve 30 is provided in the first flow passage section 24 between the first opening 22A and the second opening 23. In the embodiment of the present disclosure, the on-off valve 30 can be opened and closed by, for example, an operator of the fan device 10A, for example, a pilot or an engineer of the aircraft 1. The on-off valve 30 opens and closes based on, for example, the rotation speed of the fan device 10A. Specifically, for example, when the rotation speed of the fan device 10A becomes equal to or higher than the rotation speed N that is a preset threshold value of the rotation speed, the on-off valve 30 is opened from the closed state. On the other hand, when the rotation speed of the fan device 10A is not equal to or higher than the rotation speed N, the on-off valve 30 is closed. Here, the rotation speed N can be exemplified as a rotation speed at which the ratio of the surge flow rate G2 to the design flow rate G1 in the fan device 10A becomes greater than a preset threshold value of the ratio. In addition, the surge flow rate G2 is the flow rate of the fluid flowing through the fan device 10A when a stall occurs in either the rotor blades 12 or the stator blades 14 of the fan device 10A, forming a large backflow area and causing strong flow rate and pressure fluctuations before and after the housing 13.

[0026] In such a fan unit 10A, the rotor shaft 11 and the rotor blades 12 are rotated around the central axis Cf to generate an air flow from the front opening 15 to the rear opening 16 within the housing 13. As a result, the boundary layer formed on the outer surface 2f of the aircraft body 2 during flight is sucked into the housing 13 through the front opening 15 of the housing 13. This reduces the effects of the boundary layer. The fan unit 10A also obtains thrust by blowing the generated air flow out of the rear opening 16 of the housing 13 backward in the propulsion direction of the aircraft. The fan device 10A is provided on the outer surface 2f of the aircraft body 2. The stator vane fluid suction section 21A sucks in fluid near the stator vane tips 14t of the stator vanes 14. As indicated by the symbol Z in Fig. 2, on the front opening 15 side of the fan device 10A, the flow speed of the air becomes slower the closer it is to the outer surface 2f of the aircraft body 2 due to the influence of the boundary layer. By sucking in air near the stator vane tips 14t within the housing 13, particularly in the region on the outer surface 2f side of the aircraft body 2 with respect to the rotor shaft 11, a decrease in the flow speed of the air near the stator vane tips 14t due to the influence of the boundary layer is suppressed.

[0027] (Action and effect) In the aircraft 1 of the above embodiment, the stator vane fluid suction section 21A sucks in fluid on the stator vane tip 14t side of the stator vane 14. As a result, in the housing 13, particularly in the region on the outer surface 2f side of the aircraft body 2 with respect to the rotor shaft 11, the flow velocity of the air flow in the vicinity of the stator vane tip 14t decreases due to the influence of the boundary layer, increasing the inflow angle of the stator vane 14, and separation of the flow on the blade surface is suppressed. Therefore, stall in the vicinity of the stator vane 14 is suppressed, and separation of the air flow in the housing 13 is suppressed. In this way, it is possible to expand the operating range of the fan unit 10A and improve the propulsion efficiency of the aircraft 1.

[0028] In the above embodiment, a plurality of fan units 10A are provided at intervals in the circumferential direction Dc of the aircraft. This suppresses the influence of the boundary layer on the outer surface 2f of the aircraft main body 2 over the entire circumferential direction Dc of the aircraft, thereby suppressing stall in the vicinity of the stator blades 14.

[0029] In the above embodiment, the stator vane fluid suction portion 21A has the first flow passage portion 24 that communicates between the first opening 22A and the second opening 23 that opens rearward of the first opening 22A. As a result, in each stator vane fluid suction portion 21A, the fluid sucked in from the first opening 22A can be discharged from the second opening 23 through the first flow passage portion 24.

[0030] In the above embodiment, the stator blade fluid suction portion 21A is provided with the on-off valve 30. This allows the suction of fluid in the stator vane fluid suction portion 21A to be interrupted depending on various flight conditions, thereby achieving a good balance between the effect of suppressing stall in the vicinity of the stator vane 14 and the effect of generating thrust in the fan unit 10A.

[0031] Second Embodiment Next, a second embodiment of an aircraft according to the present disclosure will be described. In the second embodiment described below, the only difference between the first embodiment and the second embodiment is the configuration of the fluid suction portion of the fan device. Therefore, the same parts as those in the first embodiment are denoted by the same reference numerals and will not be described again.

[0032] (Fan unit configuration) 3, in a fan unit 10B of an aircraft 1 according to a second embodiment of the present disclosure, a fluid suction section 20B includes a stator vane fluid suction section 21B. The stator vane fluid suction section 21B sucks fluid on the stator vane tip 14t side on the inner side of the stator vane 14 in the fan radial direction Df. A plurality of the stator vane fluid suction sections 21B are provided at intervals in the fan circumferential direction Ds around the rotor shaft 11. Each stator vane fluid suction section 21B includes a first opening 22B, a second opening 23, a first flow passage section 24, and an on-off valve 30.

[0033] The first opening 22B opens to a stator blade tip portion 14t of each stator blade 14. In this embodiment, the first opening 22B is formed in a slit shape at the stator blade tip portion 14t that opens to a suction side surface 14b of the stator blade 14 that becomes the low pressure side when the fan device 10B is in operation. In this embodiment, the opening area of ​​the first opening 22Bp of the stator vane fluid suction portion 21Bp located on the side closer to the aircraft body 2 with respect to the rotor shaft 11 (inside in the aircraft radial direction Dp) is larger than the opening area of ​​the first opening 22Bq of the stator vane fluid suction portion 21Bq located on the side farther from the aircraft body 2 with respect to the rotor shaft 11 (outside in the aircraft radial direction Dp). For example, the opening width in the front-rear direction Da may be different between the first opening 22Bp on the inside in the aircraft radial direction Dp and the first opening 22Bq on the outside in the aircraft radial direction Dp, or the opening height in the fan radial direction Df may be different.

[0034] (Action and effect) In the second embodiment, a larger amount of fluid can be sucked in from the first opening 22Bp of the stator vane fluid suction section 21Bp arranged on the aircraft body 2 side with respect to the rotor shaft 11. In the housing 13 of the fan device 10B, the boundary layer has a stronger effect on the aircraft body 2 side with respect to the rotor shaft 11. Therefore, by sucking in a larger amount of fluid on the aircraft body 2 side with respect to the rotor shaft 11 in this manner, it is possible to effectively prevent stall from occurring near the stator vane tip 14t on the aircraft body 2 side due to the effect of the boundary layer. On the other hand, the first opening 22Bq of the stator vane fluid suction section 21Bq on the side farther from the aircraft body 2 with respect to the rotor shaft 11 can suppress a decrease in thrust by suppressing the amount of fluid sucked in.

[0035] In the above embodiment, the opening area of ​​the first opening 22B is different between the side of the rotor shaft 11 facing the main body 2 and the side away from the main body 2, but this is not limited to the above. For example, the cross-sectional area of ​​the first flow passage portion 24 may be different between the side close to the main body 2 and the side far from the main body 2. Also, for example, the opening degree of the opening / closing valve 30 may be different between the side close to the main body 2 and the side far from the main body 2.

[0036] <Third embodiment> Next, a third embodiment of an aircraft according to the present disclosure will be described. In the third embodiment described below, the only difference between the first and second embodiments is the configuration of the fluid suction portion of the fan device. Therefore, the same parts as those in the first and second embodiments are denoted by the same reference numerals and will not be described again.

[0037] As shown in FIG. 4, in a fan unit 10C of an aircraft 1 in a third embodiment of the present disclosure, a fluid suction section 20C includes a stationary blade fluid suction section 21B, a rotor blade fluid suction section 25, and an on-off valve 30.

[0038] The rotor blade fluid suction portion 25 sucks in the fluid in the housing 13 outside the rotor blade 12 in the fan radial direction Df. In this embodiment, it is assumed that a plurality of the rotor blade fluid suction portions 25 are provided at intervals in the fan circumferential direction Ds around the rotor shaft 11, but they may be slit-shaped and communicate with the fan circumferential direction Ds. The rotor blade fluid suction portion 25 is provided in the housing 13 located outside the rotor blade 12 in the fan radial direction Df or in the aircraft body 2. Each rotor blade fluid suction portion 25 has a third opening 26, a fourth opening 27, and a second flow path portion 28.

[0039] The third opening 26 opens in the fan radial direction Df to face the rotor blade tip 12s on the outer side of the rotor blade 12 in the fan radial direction Df. The position of the third opening 26 in the front-rear direction Da may be rearward (downstream) of the intermediate position 12c between the leading edge 12f and the trailing edge 12r of the rotor blade 12 at the rotor blade tip 12s in the front-rear direction Da. The fourth opening 27 opens rearward of the third opening 26 in the front-rear direction Da. In the embodiment of the present disclosure, the fourth opening 27 also serves as the second opening 23, and opens toward the rear in the front-rear direction Da at the rear of the housing 13, at the tail 2b of the aircraft body 2. The rear of the fourth opening 27 becomes a negative pressure area when the aircraft 1 is flying.

[0040] The second flow passage section 28 communicates with the third opening 26 and the fourth opening 27. The second flow passage section 28 is joined and connected to the first flow passage section 24. As a result, the fluid (air) flowing inside the housing 13 is sucked from the region near the rotor blade tip 12s, including the gap between the rotor blade tip 12s and the inner circumferential surface of the housing 13 or the outer surface 2f of the aircraft main body 2, through the third opening 26. The fluid sucked from the third opening 26 passes through the second flow passage section 28 and the first flow passage section 24 and is discharged rearward from the fourth opening 27 (second opening 23). The on-off valve 30 turns on and off the suction of fluid in each of the stationary blade fluid suction portions 21A and the rotor blade fluid suction portion 25.

[0041] In such a fan device 10C, the stator vane fluid suction section 21A sucks in fluid near the stator vane tip 14t of the stator vane 14, as in the first embodiment. Also, the rotor blade fluid suction section 25 sucks in fluid inside the housing 13 outside the fan radial direction Df of the rotor blade 12. As a result, inside the housing 13 of the fan device 10C, the effect of the boundary layer reduces the air flow velocity near the stator vane tip 14t and the rotor blade tip 12s, increasing the inflow angle of the blade, and preventing flow separation on the blade surface.

[0042] (Action and effect) In the aircraft 1 of the above embodiment, the stator vane fluid suction section 21A sucks in the fluid on the stator vane tip 14t side of the stator vane 14. The rotor vane fluid suction section 25 sucks in the fluid on the rotor vane tip 12s side. This prevents the flow velocity of the air flow near the rotor vane tip 12s from decreasing due to the influence of the boundary layer in the housing 13, particularly in the region on the outer surface 2f side of the aircraft body 2 with respect to the rotor shaft 11. This prevents stall not only near the stator vane 14 but also near the rotor vane 12, and prevents separation of the air flow in the housing 13. In this way, it is possible to expand the operating range of the fan unit 10C and improve the propulsion efficiency of the aircraft 1.

[0043] In the above embodiment, the rotor blade fluid suction portion 25 has the second flow passage portion 28 that connects the third opening 26 and the fourth opening 27 to each other. As a result, in each stator vane fluid suction portion 21A, the fluid sucked in through the third opening 26 can be discharged from the fourth opening 27 through the second flow passage portion .

[0044] In the above embodiment, the second flow passage section 28 is joined to the first flow passage section 24, and the on-off valve 30 is shared by the stator vane fluid suction section 21A and the rotor blade fluid suction section 25, but this is not limited to the above. The second flow passage section 28 and the fourth opening 27 may be provided independently of the first flow passage section 24. In addition, the on-off valve 30 may be provided in each of the first flow passage section 24 and the second flow passage section 28, and the amount of fluid suctioned in the stator vane fluid suction section 21A and the rotor blade fluid suction section 25 may be adjusted separately.

[0045] (Modification of the third embodiment) In the third embodiment, the stator vane fluid suction portion 21A and the rotor blade fluid suction portion 25 are provided, but this is not limited to this. For example, a configuration may be adopted in which only the rotor blade fluid suction portion 25 is provided without providing the stator vane fluid suction portion 21A.

[0046] <Fourth embodiment> Next, a fourth embodiment of the aircraft according to the present disclosure will be described. The fourth embodiment described below differs from the first embodiment only in that it includes a control device for the fan device. Therefore, the same parts as those in the first embodiment will be denoted by the same reference numerals and will not be described again. The control unit described in the fourth embodiment of the present disclosure can also be combined with the configurations shown in the second and third embodiments.

[0047] As shown in FIG. 5, the aircraft 1 in the fourth embodiment of the present disclosure includes a fan unit 10D and a control unit 50. The control device 50 controls the opening and closing of the on-off valve 30 of the fan device 10D. The control device 50 controls the opening and closing of the on-off valve 30 based on, for example, various data detected by the sensor 40. The sensor 40 may be, for example, a rotation speed sensor that detects the rotation speed of the fan device 10D, or a temperature sensor that detects the temperature (inlet temperature) of the air flowing into the housing 13 of the fan device 10D. Furthermore, in the case where a propeller such as a jet engine is provided in addition to the fan device 10D, the sensor 40 may detect the rotation speed of the propeller.

[0048] (Function block diagram) 6, the control device 50 realizes the respective functional configurations of a signal input unit 51, an opening / closing control unit 53, and a signal output unit 55, for example, by executing a program stored in a storage device (not shown) in advance. Note that the control device 50 may realize the above functional configurations by hardware.

[0049] The signal input unit 51 receives a detection signal from the sensor 40. The opening / closing control unit 53 determines whether the on-off valve 30 is open or closed, based on the detection signal from the sensor 40 received by the signal input unit 51. The signal output unit 55 outputs a signal to the on-off valve 30 to open or close the on-off valve 30, based on the determination result by the opening / closing control unit 53.

[0050] (Processing Procedure) As shown in FIG. 7, a fan device control method S1 according to an embodiment of the present disclosure includes a step S2 of receiving a detection signal from the sensor 40, a step S3 of determining whether the on-off valve 30 is open or closed, and a step S4 of opening and closing the on-off valve 30.

[0051] In step S2 of receiving a detection signal from the sensor 40, the signal input unit 51 receives detection signals such as the rotation speed of the fan device 10D and the inlet temperature of the housing 13 detected by the sensor 40 at preset time intervals.

[0052] In step S3, the on-off valve 30 is determined to be open or closed based on the conditions such as the rotation speed of the fan device 10D that received the detection signal in step S2 and the inlet temperature of the housing 13. The on-off valve 30 is determined to be open or closed, that is, whether to open or close the valve 30. The on-off valve 30 is determined, for example, based on the rotation speed of the fan device 10D. Specifically, for example, when the rotation speed of the fan device 10D is equal to or greater than the rotation speed N, the on-off valve 30 is opened. On the other hand, when the rotation speed of the fan device 10D is not equal to or greater than the rotation speed N, the on-off valve 30 is closed. Here, the rotation speed N is a threshold value of the rotation speed at which the ratio of the surge flow rate G2 to the design flow rate G1 in the fan device 10D becomes greater than a preset threshold value, as in the first embodiment. In this case, the rotation speed N may be corrected by the inlet temperature of the housing 13 of the fan device 10D.

[0053] In step S4 for opening and closing the on-off valve 30, the on-off valve 30 is controlled to be opened or closed based on the result of the determination in step S3. That is, if it is determined in step S3 that the on-off valve 30 is to be opened, the signal output unit 55 outputs a control signal to the on-off valve 30 to open it. If it is determined in step S3 that the on-off valve 30 is to be closed, the signal output unit 55 outputs a control signal to the on-off valve 30 to close it.

[0054] (Action and effect) In the aircraft 1 of the above embodiment, the control device 50 automatically opens and closes the on-off valve 30 in accordance with the operating conditions of the fan unit 10D, etc. This makes it possible to open and close the on-off valve 30 at appropriate timing in accordance with the state of the aircraft 1 during flight, the state of the fan unit 10D, etc. This makes it possible to effectively suppress separation of the air flow in the fan unit 10D, widen the operating range of the fan unit 10D, and improve the propulsion efficiency of the aircraft 1.

[0055] (Other embodiments) Although the embodiments of the present disclosure have been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment, and design changes and the like that do not depart from the gist of the present disclosure are also included. The order of the above steps can be changed as appropriate.

[0056] <Additional Notes> The aircraft 1 described in each embodiment can be understood, for example, as follows.

[0057] (1) An aircraft 1 according to a first aspect includes an aircraft body 2 extending in a longitudinal direction Da, a tail 4 provided at a tail 2b of the aircraft body 2 in the longitudinal direction Da, a main wing 3 provided on the aircraft body 2 forward of the tail 4 in the longitudinal direction Da, and fan units 10A to 10D provided on an outer surface 2f of the aircraft body 2, the fan units 10A to 10D being disposed outside the outer surface 2f of the aircraft body 2 in an aircraft radial direction Dp, a rotor shaft 11 rotatably provided around a central axis Cf extending in the longitudinal direction Da, and a rotor shaft 12 rotatably provided around the rotor shaft 12 . the housing 13 is fixed to the aircraft body 2, extends in the fore-and-aft direction Da, has openings 15, 16 at the front and rear of the fore-and-aft direction Da, and is provided so as to cover the rotor shaft 11 and the rotor blades 12; ... stator vanes 14 extend from an inner circumferential surface 13f of the housing 13 inward in the fan radial direction Df; and the stator vane fluid suction portions 21A, 21B that suction a fluid on the side of the stator vane tips 14t on the inside of the fan radial direction Df of the stator vanes 14.

[0058] The fan units 10A to 10D of the aircraft 1 generate an air flow from the front to the rear within the housing 13 by rotating the rotor shaft 11 and the rotor blades 12 about the central axis Cf. As a result, a boundary layer formed on the outer surface 2f of the aircraft body 2 during flight is sucked into the housing 13 through the front opening 15 of the housing 13, thereby suppressing the effects of the boundary layer. In addition, the fan units 10A to 10D can obtain thrust by blowing the generated air flow out of the rear opening 16 of the housing 13 rearward in the propulsion direction of the aircraft. Furthermore, the fan units 10A to 10D are provided on the outer surface 2f of the aircraft body 2, and the stator vane fluid suction units 21A, 21B suck the fluid on the stator vane tip 14t side of the stator vane 14. As a result, in the housing 13, particularly in the region closer to the outer surface 2f of the aircraft body 2 with respect to the rotor shaft 11, the flow velocity of the air flow in the vicinity of the stator vane tip 14t decreases due to the influence of the boundary layer, increasing the inflow angle of the stator vane 14, and preventing the flow from separating on the wing surface. In this way, it is possible to expand the operating range of the fan units 10A to 10D and improve the propulsion efficiency of the aircraft 1.

[0059] (2) The aircraft 1 of the second aspect is the aircraft 1 of (1), wherein the fan units 10A to 10D are provided at intervals in the aircraft circumferential direction Dc along the outer surface 2f of the aircraft body 2, outside the aircraft radial direction Dp of the aircraft body 2.

[0060] As a result, on the outer surface 2f of the aircraft body 2, the influence of the boundary layer is suppressed over the entire circumferential direction Dc of the aircraft, and stall in the vicinity of the stator blades 14 is suppressed.

[0061] (3) The aircraft 1 according to a third aspect is the aircraft 1 of (1) or (2), wherein the stator vane fluid suction sections 21A, 21B are provided at intervals in the fan circumferential direction Ds around the rotor shaft 11.

[0062] This makes it possible to effectively suppress stall in the vicinity of the stator blades 14 by suppressing the influence of the boundary layer over the entire area in the fan circumferential direction Ds inside the housing 13 .

[0063] (4) The aircraft 1 according to a fourth aspect is the aircraft 1 of (3), wherein each of the stator vane fluid suction sections 21 has a first flow passage section 24 that connects a first opening 22A, 22B that opens to the stator vane tip 14t and a second opening 23 that opens rearward of the first openings 22A, 22B in the fore-and-aft direction Da.

[0064] As a result, in each of the stator vane fluid suction portions 21A, 21B, the fluid sucked in from the first openings 22A, 22B can be discharged from the second openings 23 through the first flow passage portion 24.

[0065] (5) The aircraft 1 of the fifth aspect is the aircraft 1 of (4), wherein the opening area of ​​the first opening 22B of the stator vane fluid suction section 21B arranged on the side closer to the aircraft body 2 relative to the rotor shaft 11 is larger than the opening area of ​​the first opening 22B of the stator vane fluid suction section 21B arranged on the side farther from the aircraft body 2 relative to the rotor shaft 11.

[0066] This allows a larger amount of fluid to be sucked in from the first opening 22B of the stator vane fluid suction portion 21B arranged on the side closer to the aircraft body 2 with respect to the rotor shaft 11. Inside the housing 13 of the fan unit 10B, the side closer to the aircraft body 2 with respect to the rotor shaft 11 is more strongly affected by the boundary layer. This allows more fluid to be sucked in on the side closer to the aircraft body 2 with respect to the rotor shaft 11, thereby preventing stall from occurring near the stator vane tip 14t on the side closer to the aircraft body 2 due to the influence of the boundary layer. On the side farther from the aircraft body 2 with respect to the rotor shaft 11, the amount of fluid sucked in is reduced, thereby preventing a decrease in thrust.

[0067] (6) The aircraft 1 according to a sixth aspect is any one of the aircraft 1 according to (1) to (5), further comprising an on-off valve 30 that interrupts the suction of the fluid in the stator vane fluid suction sections 21A, 21B.

[0068] This allows the suction of fluid in the stator vane fluid suction portions 21A, 21B to be interrupted depending on various conditions during flight. Therefore, a good balance can be achieved between the effect of suppressing stall in the vicinity of the stator vane 14 and the generation of propulsive force by the fan units 10A to 10D.

[0069] (7) The aircraft 1 of a seventh aspect is any one of the aircraft 1 of (1) to (6), further comprising a rotor blade fluid suction portion 25 that suctions fluid in the housing 13 outside the fan radial direction Df of the rotor blade 12.

[0070] As a result, the rotor blade fluid suction section 25 sucks in the fluid on the rotor blade tip 12s side. As a result, within the housing 13, particularly in the region on the outer surface 2f side of the aircraft body 2 with respect to the rotor shaft 11, the flow velocity of the air flow near the rotor blade tip 12s decreases due to the influence of the boundary layer, increasing the inflow angle of the stator blade 14, and flow separation on the wing surface is suppressed. Therefore, stall is suppressed not only near the stator blade 14 but also near the rotor blade 12, and separation of the air flow within the housing 13 is suppressed. In this way, it is possible to expand the operating range of the fan unit 10C and improve the propulsion efficiency of the aircraft 1.

[0071] (8) An aircraft 1 according to an eighth aspect is the aircraft 1 of (7), wherein each of the blade fluid suction sections 25 has a second flow passage section 28 that communicates with a third opening 26 that opens opposite the blade tip 12s in the fan radial direction Df, and a fourth opening 27 that opens rearward of the third opening 26 in the fore-and-aft direction Da.

[0072] As a result, in each rotor blade fluid suction portion 25, the fluid sucked in from the third opening 26 can be discharged from the fourth opening 27 through the second flow passage portion 28.

[0073] (9) An aircraft 1 according to a ninth aspect includes an aircraft body 2 extending in a longitudinal direction Da, a tail 4 provided at a tail 2b of the aircraft body 2 in the longitudinal direction Da, a main wing 3 provided on the aircraft body 2 forward of the tail 4 in the longitudinal direction Da, and a fan unit 10C provided on an outer surface 2f of the aircraft body 2, the fan unit 10C being disposed outside the outer surface 2f of the aircraft body 2 in an aircraft radial direction Dp, a rotor shaft 11 rotatably provided around a central axis Cf extending in the longitudinal direction Da, and a rotor shaft 12 rotatably provided around the rotor shaft 12 . the rotor shaft 11 is provided with a rotor blade 12 arranged on the outside of the rotor shaft 11 in a fan radial direction Df; a housing 13 fixed to the aircraft body 2, extending in the fore-and-aft direction Da and having openings 15, 16 at the front and rear of the fore-and-aft direction Da, respectively, arranged to cover the rotor shaft 11 and the rotor blade 12; vanes 14 extending inward in the fan radial direction Df from an inner circumferential surface 13f of the housing 13; and a rotor blade fluid suction portion 25 that is located outside the rotor blade 12 in the fan radial direction Df and that sucks in the fluid in the housing 13.

[0074] The fan unit 10C of the aircraft 1 is provided on the outer surface 2f of the aircraft body 2. The rotor blade fluid suction unit 25 sucks in the fluid on the rotor blade tip 12s side. As a result, in the housing 13, particularly in the region closer to the outer surface 2f of the aircraft body 2 with respect to the rotor shaft 11, the flow velocity of the air flow near the rotor blade tip 12s decreases due to the influence of the boundary layer, increasing the inflow angle of the rotor blade 12, and preventing the flow from separating on the blade surface. Therefore, stall near the rotor blade 12 is prevented, and the separation of the air flow in the housing 13 is prevented. In this way, it is possible to expand the operating range of the fan unit 10C and improve the propulsion efficiency of the aircraft 1. [Explanation of symbols]

[0075] 1...Aircraft 2…Aircraft body 2a…nose 2b…Stern 2f…Outer surface 3…Wing 4...tail wing 4a…Vertical stabilizer 10A~10D...Fan unit 11...Rotor shaft 12... Moving blade 12c…Intermediate position 12f…leading edge 12r… Trailing edge 12s…Rotor blade tip 13. Housing 13f…Inner peripheral surface 14…Stationary blade 14a...ventral surface 14b…dorsal surface 14c…Intermediate position 14f…leading edge 14r… Trailing edge 14t…Stator blade tip 15, 16...Aperture 20A~20C…Fluid suction part 21A, 21B, 21Bp, 21Bq...Stator vane fluid suction part 22A, 22B, 22Bp, 22Bq...first opening 23...Second opening 24...First flow path section 25…Rotor blade fluid suction section 26…Third opening 27…Fourth opening 28...Second flow path section 30...Shut-off valve 40…Sensor 50...Control device 51...Signal input section 53...Opening and closing control section 55...Signal output section Cf…center axis

Claims

1. An aircraft main body extending in the front-rear direction; A tail provided at a rear portion of the aircraft body in the longitudinal direction; A main wing provided forward of the tail in the longitudinal direction on the aircraft body; a fan device provided on an outer surface of the aircraft body, The fan device is A rotor shaft is disposed radially outward of the outer surface of the aircraft body and is rotatably provided around a central axis extending in the front-rear direction; A rotor blade is provided on the outer side of the rotor shaft in a radial direction of the rotor with the rotor shaft as a center; a housing fixed to the aircraft body, extending in the front-rear direction, having openings at the front and rear in the front-rear direction, and provided to cover the rotor shaft and the rotor blades; a stator blade extending inward in a radial direction of the rotor from an inner circumferential surface of the housing; a stator blade fluid suction portion that suctions a fluid on a stator blade tip side on the inner side in the rotor radial direction of the stator blade. aircraft.

2. The fan devices are provided at intervals in a circumferential direction of the aircraft along an outer surface of the aircraft body on the outer side of the aircraft body in the radial direction of the aircraft body.

2. The aircraft of claim 1.

3. The stator vane fluid suction portion is provided in a plurality of locations spaced apart from one another in a circumferential direction of the rotor about the rotor shaft. An aircraft as claimed in claim 1 or 2.

4. Each of the stator vane fluid suction portions includes: a first flow passage portion that communicates a first opening portion that opens to the tip portion of the stator blade and a second opening portion that opens rearward of the first opening portion in the front-rear direction; 4. An aircraft as claimed in claim 3.

5. An opening area of ​​the first opening of the stator vane fluid suction portion arranged on a side closer to the aircraft body with respect to the rotor shaft is larger than an opening area of ​​the first opening of the stator vane fluid suction portion arranged on a side farther from the aircraft body with respect to the rotor shaft.

5. An aircraft as claimed in claim 4.

6. The stationary blade fluid suction portion further includes an on-off valve for turning on and off the suction of the fluid. An aircraft as claimed in any one of claims 1 to 5.

7. a rotor blade fluid suction portion that suctions the fluid in the housing on the outer side of the rotor blade in the rotor radial direction. An aircraft as claimed in any one of claims 1 to 6.

8. Each of the rotor blade fluid suction portions includes: a second flow passage portion that communicates a third opening portion that opens opposite to the rotor tip portion in the rotor radial direction and a fourth opening portion that opens rearward of the third opening portion in the front-rear direction; 8. An aircraft as claimed in claim 7.

9. An aircraft main body extending in the front-rear direction; A tail provided at a rear portion of the aircraft body in the longitudinal direction; A main wing provided forward of the tail in the longitudinal direction on the aircraft body; a fan device provided on an outer surface of the aircraft body, The fan device is A rotor shaft is disposed radially outward of the outer surface of the aircraft body and is rotatably provided around a central axis extending in the front-rear direction; A rotor blade is provided on the outer side of the rotor shaft in a radial direction of the rotor with the rotor shaft as a center; a housing fixed to the aircraft body, extending in the front-rear direction, having openings at the front and rear in the front-rear direction, and provided to cover the rotor shaft and the rotor blades; a stator blade extending inward in a radial direction of the rotor from an inner circumferential surface of the housing; a rotor blade fluid suction portion that suctions the fluid in the housing on the outer side of the rotor blade in the rotor radial direction. aircraft.

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