Wing

Abstract

To provide a wing capable of greatly improving fluid dynamic performance by reducing only drag without impairing lift.SOLUTION: A blade (1) includes a streamlined blade body (10) that contacts a fluid (F), and a vibration source (20) that applies ultrasonic micro-vibration to surfaces of the blade body (10) by micro-ultrasonic waves, wherein the vibration source (20) generates a downstream traveling wave within a range of a chord length of 0.5 to 1. 0Lc in an airfoil of the blade body (10).SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a wing. [Background technology]

[0002] The hydrodynamic performance of a wing can be evaluated by the lift-to-drag ratio (lift / drag), which is the ratio of the fluid force acting on the wing, which is the component perpendicular to the fluid flow, to the component parallel to the fluid flow, which is the drag.Drag has a significant effect on the energy consumption performance of a winged mobile object, so reducing drag is extremely important, and research has been widely conducted to reduce drag by controlling turbulence on the wing surface.

[0003] These studies focus on techniques for delaying the transition from laminar flow to a turbulent boundary layer in the flow field around an airfoil and manipulating the turbulent structure near the surface of the airfoil, and can be broadly divided into passive control and active control. Passive control techniques include techniques for suppressing the generation of turbulence near the surface of the airfoil and reducing frictional drag by modifying the surface shape of the airfoil by creating vertical or horizontal slots, adding surface roughness, adding riblets, or using flaps. However, at present, passive control has not been able to achieve sufficient drag reduction performance. Active control techniques, such as those described in Patent Document 1, are known for reducing frictional drag with a fluid by applying ultrasonic vibrations to the outer wall of a moving object that comes into contact with the fluid. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2011-185409 A (pages 4 to 5, Figure 1) Summary of the Invention [Problem to be solved by the invention]

[0005] However, although the technology of Patent Document 1 can achieve a certain degree of drag reduction performance by being applied to the entire exterior wall of the aircraft body, including the wings, it has the problem that the lift generated on the wings is impaired, worsening the lift-to-drag ratio and making it impossible to achieve sufficient hydrodynamic performance.

[0006] The present invention has been made in response to these problems, and aims to provide a wing that can significantly improve hydrodynamic performance by reducing drag without impairing lift. [Means for solving the problem]

[0007] In order to solve the above problems, the blade of the present invention comprises: A wing comprising a streamlined wing body that comes into contact with a fluid and a vibration source that applies ultrasonic micro-vibrations to the surface of the wing body using micro-ultrasonic waves, The vibration source has a chord length of 0.5 to 1.0L in the airfoil of the wing body. c The present invention is characterized by generating a downstream traveling wave within a range of . This feature does not affect the global flow field around the wing, and by changing the velocity and pressure distribution near the wall of the turbulent boundary layer formed near the surface of the wing body subjected to ultrasonic micro-vibrations, it is possible to reduce drag without compromising lift, thereby increasing the lift-to-drag ratio and significantly improving hydrodynamic performance.

[0008] The vibration source has a chord length of 0.7 to 1.0L in the airfoil of the wing body. c The present invention is characterized by generating a downstream traveling wave within a range of . This feature allows the lift-to-drag ratio to be increased with high efficiency.

[0009] The angle of attack of the wing body is characterized by being 0 to 10°. This feature allows the lift-to-drag ratio to be increased with high efficiency.

[0010] The vibration source is characterized by generating downstream traveling waves on both the upper and lower surfaces of the blade body. According to this feature, the drag generated on the wing body can be reduced with high efficiency.

[0011] The vibration source is characterized by generating downstream traveling waves of the same motion on both the upper and lower surfaces of the blade body. This feature allows the lift-to-drag ratio to be increased with high efficiency. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a diagram showing an example of a configuration of a wing in an embodiment according to the present invention. FIG. [Figure 2] (a) is a diagram showing the fluid flow field when a downstream traveling wave is applied to the surface of a flat plate model from a vibration source, (b) is an enlarged view of the fluid flow field in the boxed area of ​​(a), (c) is a diagram showing the fluid flow field when an upstream traveling wave is applied, (d) is an enlarged view of the fluid flow field in the boxed area of ​​(c), (e) is a diagram showing the fluid flow field when a standing wave is applied, and (f) is an enlarged view of the fluid flow field in the boxed area of ​​(e). [Figure 3] This is a graph showing the changes in pressure drag CP, friction drag CF, and total drag CD when a downstream traveling wave, an upstream traveling wave, and a standing wave are applied to the surface of a flat plate model as ultrasonic micro-vibrations from a vibration source. [Figure 4] FIG. 2 is a diagram showing the airfoil of a wing body constituting a wing in the embodiment. [Figure 5] (a) is a graph comparing the velocity distribution of the fluid near the surface of the blade body with and without ultrasonic micro-vibration (downstream traveling wave), and (b) is a graph comparing the pressure distribution of the same. [Figure 6] (a) is a graph comparing the overall time-averaged lift force CL with and without ultrasonic micro-vibration (downstream traveling wave), (b) is a graph comparing the time-averaged total drag force CD, and (c) is a graph comparing the lift-to-drag ratio CL / CD. The rate of change shown in each graph is calculated by (Cvib-Cnovib) / Cnovib x 100%. [Figure 7](a) is a diagram showing the position of the vibration region on the upper surface of the blade body where a single vibration of a downstream progressive wave is applied from a vibration source, and (b) is a diagram showing the position of the vibration region on both the upper and lower surfaces of the blade body where a double vibration of a downstream progressive wave is applied from a vibration source. [Figure 8] (a) is a graph showing the change in lift force CL versus angle of attack (AoA) under different vibration conditions (no vibration, single vibration, double vibration), (b) is a graph showing the change in total drag force CD versus angle of attack, and (c) is a graph showing the change in lift-to-drag ratio CL / CD versus angle of attack. [Figure 9] This graph shows the rate of change of lift CL, total drag CD, and lift-to-drag ratio CL / CD in each vibration region on the upper and lower surfaces of the wing body. Each rate of change is calculated by (Cvib-Cnovib) / Cnovib x 100%. [Figure 10] (a) is a diagram showing the airfoil of a wing body with an optimized vibration region, (b) is a diagram showing an image in which double vibrations (identical motion) of downstream progressive waves are applied to both the upper and lower surfaces of the wing body, and (c) is a diagram showing an image in which double vibrations (symmetrical motion) of downstream progressive waves are applied. [Figure 11] (a) and (b) are graphs showing the changes in instantaneous lift (Cl) and instantaneous total drag (Cd) for two adjacent periods for an angle of attack of 0° under different motion conditions (identical motion, symmetric motion, no vibration), (c) and (d) are graphs showing the changes in instantaneous lift (Cl) and instantaneous total drag (Cd) for an angle of attack of 7.5°, and (e) and (f) are graphs showing the changes in instantaneous lift (Cl) and instantaneous total drag (Cd) for an angle of attack of 10°. [Figure 12] (a) to (c) are graphs comparing the overall time-averaged lift CL, total drag CD, and lift-to-drag ratio CL / CD acting on a wing with angles of attack of 0°, 7.5°, and 10° under different motion conditions (identical motion, symmetrical motion, no vibration). The rate of change shown in each graph is calculated by (Cvib-Cnovib) / Cnovib×100%. DETAILED DESCRIPTION OF THE INVENTION

[0013] The blade according to the present invention will be described below. [Example]

[0014] A wing according to an embodiment will be described with reference to Figures 1 to 12. In this embodiment, the wing is applied to an aerial vehicle such as an airplane, helicopter, or drone, and the fluid that comes into contact with the wing is a gas such as air.

[0015] As shown in Figure 1, the wing 1 of this embodiment is applied, for example, to the main wing of an aircraft, and comprises a streamlined wing body 10 that comes into contact with a fluid F, and a vibration source 20 that applies ultrasonic micro-vibrations (hereinafter sometimes simply referred to as "vibrations") to the surface of the wing body 10 using micro-ultrasonic waves.

[0016] The wing body 10 is mainly formed from an aluminum alloy, a carbon fiber composite material (CFRP), etc. The surface of the wing body 10 is smooth when no vibration is applied from the vibration source 20. The surface of the wing body 10 may be flat or curved.

[0017] The vibration source 20 is provided on both the upper and lower surfaces inside the blade body 10, and has vibrators (not shown) that generate micro ultrasonic waves. As the vibrators, for example, electrostrictive or magnetostrictive vibrators such as a bolt-clamped Langevin (BL) vibrator, a ferrite vibrator, or a lead zirconate titanate (PZT) vibrator can be used.

[0018] In FIG. 1, a plurality of vibration sources 20 are arranged on the trailing edge side of the blade body 10 along the flow direction of the fluid F that contacts the blade body 10 (see the outline arrow).

[0019] The vibration source 20 is configured to generate longitudinal micro ultrasonic waves having ultrasonic frequency vibrations and minute amplitudes. The longitudinal micro ultrasonic waves are compressional waves that have displacement in the same direction as the wave propagation direction.

[0020] The vibration source 20 applies ultrasonic micro-vibrations to the surface of the wing-body 10 using longitudinal micro-ultrasonic waves. This causes the surface of the wing-body 10 to vibrate at a predetermined frequency and maximum amplitude. In this embodiment, the vibration source 20 applies vibrations to the surface of the wing-body 10 using longitudinal micro-ultrasonic waves, making it easier to control the direction of travel and waveform characteristics of the vibrations generated on the surface of the wing-body 10.

[0021] In this embodiment, the vibration generated on the surface of the wing-body 10 is a sinusoidal wave perpendicular to the surface of the wing-body 10, and is a so-called downstream traveling wave that propagates in the flow direction of the fluid F (see FIG. 2(a)). In FIG. 1, the propagation direction of the downstream traveling wave is indicated by a dashed arrow.

[0022] The frequency of the vibration (downstream traveling wave) generated on the surface of the blade body 10 is preferably 10 kHz or more and 250 kHz or less. The maximum amplitude of the vibration is preferably 10 μm or more and 20 μm or less. The wavelength of the vibration is preferably 100 μm or more and 150 μm or less. The propagation speed of the vibration is preferably 5 m / sec or more and 15 m / sec or less.

[0023] As shown in Figure 2, comparing the flow fields of a fluid when downstream traveling waves, upstream traveling waves, and standing waves are applied from a vibration source to the surface of a flat plate model, the flow field in the viscous sublayer formed near the surface of the vibrating flat plate model changes. In this way, downstream traveling waves, upstream traveling waves, and standing waves are applied from a vibration source to the surface of the flat plate model, and the flow field near the surface changes, causing the pressure drag C P , frictional drag C F、 Total drag C D (See Figure 3.) The dotted line in Figure 3 indicates the value of the total drag force when there is no vibration. In particular, when a downstream traveling wave is applied to the surface of the flat plate model from the vibration source, the friction drag C F increases, but the pressure drag C P is significantly reduced, resulting in a total drag force C DIn other words, when a downstream traveling wave is applied to the surface of the flat plate model from a vibration source, the total drag force C D It is possible to completely eliminate this and convert it into thrust.

[0024] In this embodiment, in order to increase the lift-to-drag ratio of the wing 1 and improve the aerodynamic performance, the vibration source 20 is arranged to have a chord length of 0.5 to 1.0L in the airfoil of the wing body 10 (see FIG. 4). c It is preferable to generate a downstream progressive wave within the range of 0.7 to 1.0L. c It is more preferable to generate a downstream traveling wave within the range of

[0025] In this embodiment, the range in which vibration is applied from the vibration source 20 is called the "vibration region." c The range is 0.5 to 1.0L for chord lengths. c For example, the vibration region has a chord length of 0.8 to 0.9L. c The range and chord length are 0.7~1.0L. c This includes those in the range of

[0026] The airfoil is a cross section of the wing body 10 cut longitudinally along the chord C, as shown in FIG. c is the position of the leading edge of the wing body 10, 1.0L c indicates the position of the trailing edge of the wing-body 10. In this embodiment, the wing-body 10 employs the standard NACA0012 airfoil.

[0027] The vibration source 20 can selectively control the vibration pattern between "single vibration" (see FIG. 7(a)) which generates a downstream traveling wave on either the upper surface 10a or the lower surface 10b of the wing-body 10, and "double vibration" (see FIG. 7(b)) which generates a downstream traveling wave on both the upper surface 10a and the lower surface 10b of the wing-body 10. Furthermore, in the case of double vibration, the vibration source 20 can selectively control between "identical motion" (see FIG. 10(b)) in which the motion phase difference in the vibration regions of the upper surface 10a and the lower surface 10b of the wing-body 10 is 0, and "symmetric motion" (see FIG. 10(b)) in which the motion phase difference in the vibration regions of the upper surface 10a and the lower surface 10b of the wing-body 10 is π so as to be symmetrical with respect to the center line of the wing shape.

[0028] Below, we will explain the results of a simulation of the effect obtained by applying a downstream traveling wave from the vibration source 20 to the surface of the blade body 10 for the blade 1 of this embodiment. In the following simulation, the downstream traveling wave applied from the vibration source 20 to the surface of the blade body 10 is a vibration with a frequency of 100 kHz, an amplitude of 20 μm, a wavelength of 150 μm, and a propagation speed of 15 m / sec.

[0029] (Simulation 1) The vibration area from the vibration source 20 to the upper surface 10a of the wing body 10 is 0.8 to 0.9L. c When a single vibration downstream traveling wave is applied to the blade 1, as shown in Figure 5(a), it has been confirmed that the downstream traveling wave affects only the velocity distribution near the surface of the blade body 10 due to the small amplitude characteristics of the longitudinal wave micro ultrasonic waves generated by the vibration source 20, and does not have a significant effect on the entire flow field around the blade 1.

[0030] 5(b), it was confirmed that the downstream progressive wave periodically fluctuates the pressure distribution near the surface of the wing body 10. Furthermore, although the downstream progressive wave slightly increases the pressure around the wing 1, its effect on the overall pressure field around the wing 1 is limited.

[0031] Here, the lift is determined by the pressure distribution on the surface of the wing-body 10, so the periodic pressure fluctuations near the surface of the wing-body 10 described above are the instantaneous lift Cl However, the influence of the downstream traveling wave on the pressure distribution is limited to the vicinity of the surface of the wing-body 10. Therefore, the overall time-averaged lift C before and after the downstream traveling wave is applied to the surface of the wing-body 10 L The rate of change is 0.56%, which can be almost ignored (see Figure 6(a)).

[0032] Also, the instantaneous total drag C d The lift force C is also subject to periodic and instantaneous fluctuations due to fluctuations in pressure and velocity near the surface after a downstream progressive wave is applied to the surface of the wing-body 10. However, the lift force C is hardly affected by the downstream progressive wave on the surface of the wing-body 10. L Unlike the friction drag C on the surface of the wing-body 10, F increases, but the pressure drag C P is significantly reduced, so the overall time-averaged total drag force C D The rate of change is -15.88%, which is a significant reduction (see Figure 6(b)).

[0033] In this way, the downstream progressive wave imparted to the surface of the wing body 10 from the vibration source 20 significantly reduces the drag without impairing the lift, thereby reducing the lift-to-drag ratio C L / C D The rate of change was 19.54%, and it was confirmed that the lift-to-drag ratio was increased and the aerodynamic performance of wing 1 was significantly improved (see Figure 6(c)).

[0034] (Simulation 2) Next, we explain the effect of variations in the angle of attack α on the distribution of lift and total drag. In addition, in this simulation, we compare the vibration patterns of downstream progressive waves between single vibration and double vibration (same motion) (see Figure 7).

[0035] As shown in Figure 8(a), the lift force C L Since the lift force C corresponding to the single oscillation and the double oscillation is hardly affected by the downstream traveling wave, L is consistent with the case of no vibration at angles of attack of 0 to 10°, and the lift force C LA tendency for this to increase was confirmed.

[0036] In contrast, as shown in Fig. 8(b), the total drag force C corresponding to the single and double vibrations D It was confirmed that the total drag C was reduced compared to the case without vibration at angles of attack of 0 to 10 degrees, and that the reduction was particularly large in the case of double vibration. D An increasing trend was confirmed.

[0037] In this way, a downstream progressive wave is applied to the surface of the wing body 10 from the vibration source 20, and the lift force C L Without any loss of resistance, the total drag force C D is reduced, so the lift-to-drag ratio C L / C D It was confirmed that the lift-to-drag ratio C can be improved (see FIG. 8(c)). In addition, by setting the angle of attack α to be preferably 6 to 10 degrees, more preferably 7.5 to 8.5 degrees, L / C D It was confirmed that this could be increased efficiently.

[0038] Furthermore, the vibration source 20 generates dual vibrations (same motion) of downstream progressive waves on both the upper and lower surfaces of the wing body 10, thereby reducing the total drag C D is significantly reduced, and the lift-to-drag ratio C L / C D It was confirmed that this could be increased efficiently.

[0039] (Simulation 3) Next, we will explain the effect of the position of the vibration region on the wing-body 10 on the drag reduction performance. In this simulation, the angle of attack is set to 7.5°, and the vibration region is moved from the leading edge to the trailing edge of the wing-body 10 in vibration units of 0.1Lc, while generating a single vibration of a downstream progressive wave on each of the upper surface 10a and the lower surface 10b of the wing-body 10 in 10 patterns of vibration region in Figure 9. For example, the first vibration region is expressed as [0.05, 015Lc].

[0040] As shown in Figure 9(a) and (b), the lift force C LThe rate of change of is distributed around 0 in all vibration regions, but the total drag C D It was confirmed that the rate of change of varies depending on the position of the vibration region.

[0041] In detail, the total drag C on both the upper and lower surfaces of the wing body 10 D The rate of change of increases from the vibration region [0.05, 0.15Lc] near the leading edge of the wing-body 10 to the vibration region [0.2, 0.3Lc] including the maximum thickness position of the wing-body 10, but is generally reduced from the vibration region [0.3, 0.4Lc] to the vibration region [0.9, 1.0Lc] including the trailing edge of the wing-body 10. In addition, the total drag C D The rate of change is smallest at about 2% when the vibration region includes the maximum thickness position of the wing body 10, and is improved by up to about 20% in the vibration region [0.8, 0.9Lc] of the upper surface 10a and the vibration region [0.9, 1.0Lc] of the lower surface 10b, which are away from the maximum thickness position of the wing body 10.

[0042] For these reasons, the position of the vibration region is preferably within the chord length range of 0.5 to 1.0Lc in the airfoil of the wing body 10, more preferably within the chord length range of 0.7 to 1.0Lc, thereby improving the drag reduction performance and increasing the lift-to-drag ratio with high efficiency.

[0043] Furthermore, when the angle of attack in this simulation is 7.5°, it is found that the flow distribution of the fluid F, i.e., the velocity distribution and pressure distribution of the fluid F on the surface of the wing-body 10, becomes more asymmetric when vibration is applied to the upper surface 10a of the wing-body 10 than to the lower surface 10b, making it easier to improve drag reduction performance. Note that when the angle of attack is 0°, it is found that the velocity distribution and pressure distribution of the fluid F on the surface of the wing-body 10 become symmetrical from top to bottom, and the drag reduction performance on both the top and bottom surfaces of the wing-body 10 becomes approximately equal.

[0044] 9(a), the drag reduction performance is lower in the vibration region [0.9, 1.0Lc] of the upper surface 10a of the wing-body 10 than in the vibration region [0.8, 0.9Lc]. This is presumably due to the separation of the flow near the trailing edge caused by the large angle of attack of 7.5° in this simulation.

[0045] (Simulation 4) Next, a comparison is made when double vibrations (identical motion, symmetrical motion) are generated in the vibration region 0.7 to 1.0Lc of the wing-body 10 at angles of attack of 0°, 7.5°, and 10° (see FIG. 10).

[0046] As shown in Figures 11(a), (c), and (e), the instantaneous lift force C when the phase difference between the double vibrations on the upper and lower surfaces of the wing body 10 is symmetrical is l It was confirmed that the amplitude does not fluctuate significantly from around 0, compared to the waveform fluctuations when the phase difference between the dual vibrations is the same.

[0047] Also, as shown in Figures 11(b), (d), and (f), the instantaneous total drag force C d It was confirmed that the phase difference between the double vibrations on both the upper and lower surfaces of the wing body 10 exhibited a wave-like fluctuation whether the motion phase difference was controlled to be the same or symmetrical motion, and that the fluctuations were of the same order especially at an angle of attack of 7.5°. d The magnitude of the fluctuation of the instantaneous lift force C l Since the magnitude of the fluctuation is less than 1 / 10 of the magnitude of the fluctuation (see Figures 11(a), (c), and (e)), the effect on the lift-to-drag ratio is limited.

[0048] The overall time-averaged lift C in this simulation L , total drag C D and lift-to-drag ratio C L / C D As shown in Figure 12(a) and (b), when the conditions such as vibration pattern, vibration area, and vibration region position are the same, the lift force C LTotal drag C without compromising D was confirmed to be significantly reduced.

[0049] In detail, when the angle of attack is 0°, whether the phase difference of the double vibration in the vibration region is controlled to the same motion or the symmetrical motion, the total drag C D was reduced to about -127% (see Figure 12(a)). At this time, the total drag force C D is a negative value, and as with the flat plate model, the total drag C D This shows that it is possible to completely eliminate the heat and convert it into thrust.

[0050] In addition, when the angle of attack is 7.5°, the total drag C is smaller than when there is no vibration, regardless of whether the phase difference of the double vibrations in the vibration region is controlled to the same motion or symmetrical motion. D is reduced to about -94% (see Fig. 12(a)), and in the case of an angle of attack of 10°, it is reduced to about -73% (see Fig. 12(a)). These results show that by reducing the angle of attack α, the total drag C D This shows that the

[0051] Also, as shown in Figure 12(c), when the angle of attack is 10°, the lift-to-drag ratio C L / C D increased by 2.87 times in both the same and symmetrical motions, and the lift-to-drag ratio C L / C D Furthermore, when the angle of attack was 7.5°, the lift-to-drag ratio C L / C D is increased by about 19 times in the same motion and about 16 times in the symmetric motion. When the phase difference of the double vibrations in the vibration region is controlled to the same motion, the lift-drag ratio C L / C D It was confirmed that the efficiency could be increased.

[0052] As explained above, the blade 1 of this embodiment has a surface of the blade body 10, more specifically, a chord length of 0.5 to 1.0L in the airfoil of the blade body 10. c Within the range of chord length, preferably 0.7 to 1.0Lc By applying a downstream progressive wave within the range of , the global flow field around the wing 1 is not affected, and the velocity distribution and pressure distribution near the wall of the turbulent boundary layer formed near the surface of the wing body 10 subjected to ultrasonic micro-vibration are changed, thereby increasing the lift C L Total drag C without compromising D can be significantly reduced, so that the lift-to-drag ratio C L / C D is significantly increased, and the aerodynamic performance of the wing 1 can be significantly improved.

[0053] Furthermore, when a downstream progressive wave is applied to the surface of the wing-body 10, periodic fluctuations occur in the velocity and pressure of the fluid F on the surface of the wing-body 10, but the strength of the instantaneous fluctuations within the cycle is proportional to the overall time-averaged lift C L and the total drag force C D Since this does not affect the change in the angle of attack of the wing 1, it is possible to flexibly change conditions such as the vibration pattern (single vibration, double vibration), vibration area, position of the vibration area, and motion phase difference (same motion, symmetric motion) to reduce drag, thereby significantly improving the aerodynamic performance of the wing.

[0054] In addition, the vibration source 20 applies ultrasonic micro-vibrations to the surface of the wing body 10 using ultrasonic frequency vibrations and longitudinal wave micro-ultrasonic waves with minute amplitude, making it easy to control the direction of propagation and waveform characteristics of the ultrasonic micro-vibrations generated on the surface of the wing body 10.

[0055] In addition, the chord length of the airfoil of the wing body 10 is 0.5 to 1.0L. c Within the range of chord length, preferably 0.7 to 1.0L c By increasing the vibration area that generates the downstream traveling wave within this range, the drag reduction performance can be improved.

[0056] Although the embodiments of the present invention have been described above with reference to the drawings, the specific configuration is not limited to these embodiments, and the present invention also includes modifications and additions that do not deviate from the gist of the present invention.

[0057] For example, the airfoil of the airfoil body 10 of the airfoil 1 of the above embodiment is not limited to the standard airfoil NACA0012, and any airfoil may be adopted. In this case, the chord length of the airfoil is 0.5 to 1.0L. c If it is possible to generate downstream traveling waves within this range, it goes without saying that by optimizing conditions such as the angle of attack, vibration pattern, vibration area, and motion phase difference to suit the wing shape, it is possible to reduce drag without compromising lift, and thereby increase the lift-to-drag ratio.

[0058] Furthermore, in the above embodiment, the fluid F that the blade 1 comes into contact with is a gas such as air, but this is not limited to this, and the fluid that the blade comes into contact with may also be a liquid such as fresh water or seawater.

[0059] Furthermore, in the above embodiments, the wing 1 has been described as being applied to aerial vehicles such as airplanes, helicopters, drones, etc., but this is not limited thereto. The wing of the present invention may also be applied to land vehicles (for example, automobiles such as passenger cars, buses, and trucks, and trains such as electric trains, bullet trains, and linear motor cars), water vehicles (for example, ships such as passenger ships, cargo ships, fishing boats, research vessels, yachts, and canoes), and underwater vehicles (for example, submarines). [Industrial Applicability]

[0060] The present invention is directed to a wing having a chord length of 0.5 to 1.0L in the airfoil of the wing body constituting the wing. c By generating a downstream traveling wave within this range, it is possible to significantly reduce drag without losing lift, or to completely eliminate all drag and convert it into thrust, thereby increasing the lift-to-drag ratio and significantly improving hydrodynamic performance, making the wing of the present invention particularly applicable industrially as a means of improving the energy consumption performance of various mobile bodies such as aircraft and ships. Furthermore, the wing of the present invention has a wide range of applications, as it can flexibly change conditions such as the angle of attack, vibration pattern (single vibration, double vibration), vibration area, position of the vibration region, and motion phase difference (same motion, symmetric motion) to reduce drag without losing lift. [Explanation of symbols]

[0061] 1 wing 10 Wings 10a above 10b below 20 Vibration Sources C chord F fluid

Claims

1. A wing comprising a streamlined wing body that comes into contact with a fluid and a vibration source that applies ultrasonic micro-vibrations to the surface of the wing body using micro-ultrasonic waves, The vibration source has a chord length of 0.5 to 1.0L in the airfoil of the wing body. ｃ A wing characterized by generating a downstream progressive wave within a range.

2. The vibration source has a chord length of 0.7 to 1.0L in the airfoil of the wing body. ｃ 2. The blade of claim 1, wherein the blade generates a downstream progressive wave within a range of .mu.m.

3. 3. The wing according to claim 1, wherein the angle of attack of the wing body is 0 to 10 degrees.

4. The blade according to claim 1 or 2, wherein the vibration source generates downstream traveling waves on both the upper and lower surfaces of the blade body.

5. The airfoil according to claim 4, wherein the vibration source generates downstream traveling waves of the same motion on both the upper and lower surfaces of the airfoil body.

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