Distributed electric propulsion propeller slipstream wing lift measurement device

Abstract

The application discloses a distributed electric propulsion propeller slipstream wing lift measuring device, which comprises a base, a free flow power mechanism and a front-rear moving mechanism arranged on the base, a lifting mechanism arranged on the front-rear moving mechanism, a measuring mechanism arranged on the lifting mechanism, and an attack angle adjusting mechanism arranged on the measuring mechanism and used for fixing a wing to be detected; the power output directions of a plurality of free flow propellers of the free flow power mechanism are all directed to a fairing; the front-rear moving mechanism is used for adjusting the distance between the wing and the fairing; the lifting mechanism is used for adjusting the placing height of the wing; the measuring mechanism is used for monitoring the stress condition of the wing; and the attack angle adjusting mechanism is used for adjusting the placing angle of the wing; thereby, a propeller and wing aerodynamic coupling test device is built, the propeller slipstream wing lift increment can be more accurately obtained compared with the computational fluid dynamics method, and a large amount of effective data can be quickly and cheaply obtained compared with the wind tunnel test.

Description

Technical Field

[0001] This invention relates to the technical field of slipstream wing lift measurement, and particularly to a distributed electric propulsion propeller slipstream wing lift measurement device. Background Technology

[0002] Distributed electric propulsion (DEP) aircraft are a new type of aircraft that emerged with the development of electric aircraft. They generate primary thrust by using electric motors to drive multiple propellers or ducted fans distributed across the wings and other components. A strong coupling exists between the aerodynamics and propulsion system of DEP aircraft. Effectively utilizing this aerodynamic coupling can suppress airflow separation on the wing surface, increase dynamic pressure on the wing surface, and reduce bending moment at the wing root, thereby improving aerodynamic efficiency, reducing wing area to decrease structural weight, and enhancing aircraft performance. Measuring wing lift under slipstream conditions is a crucial task.

[0003] Currently, wing lift measurement mainly focuses on wing lift measurement under free flow conditions. Patent 201911222630.2 discloses a wing lift measurement device and method, which includes a measurement circuit and a wind tunnel with an airflow channel. A bracket is installed on the outer wall of the airflow channel, and a horizontal cantilever arm is installed on the bracket. The other end of the cantilever arm extends into the airflow channel, and a detachable connecting rod is installed at one end of the cantilever arm extending into the airflow channel. The other end of the connecting rod is equipped with a wing. Patent 201620762391.5 provides a wing aerodynamics experimental simulation device. The device includes an experimental platform with a slide rail. A fan, a slidable wire support, and a wing model support are sequentially mounted on the slide rail. The fan is fixed to one end of the slide rail. Wires are mounted on the upper end of the wire support, and a wing model is mounted on the upper end of the wing model support. The wires float across the surface of the wing model under the action of the fan. The lower part of the experimental platform is also equipped with a touch screen for inputting experimental parameters and a driving black box. The touch screen controls the distance between the wire support and the wing model support on the slide rail and the fan by connecting to the driving black box.

[0004] As can be seen from the above, such experimental devices can only test the lift of small-sized models or a single propeller due to size limitations. They cannot test large-sized test objects. Increasing the size of the device would greatly increase the cost.

[0005] In addition, traditional experimental testing equipment is limited by size and cannot test wings with multiple propellers. Although it can test wings with a single propeller, the results are greatly affected by other factors and often fail to meet the requirements of academic research.

[0006] Furthermore, there are two existing technologies for measuring the aerodynamic coupling between propellers and wings. One is to use computational fluid dynamics to perform numerical simulation. However, since the propeller slipstream field cannot be accurately described theoretically, this method requires a large number of assumptions, and the results are difficult to accurately depict the coupling characteristics between the wing and the propeller. The other is wind tunnel testing. This method can accurately obtain the aerodynamic interference laws between the wing and the propeller, but it is costly and the models used have size limitations.

[0007] Therefore, how to build a propeller-wing aerodynamic coupling test device that can more accurately obtain the lift increment of the propeller slipstream on the wing compared to computational fluid dynamics methods, and can quickly and cheaply obtain a large amount of effective data compared to wind tunnel testing, has become a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0008] The purpose of this invention is to provide a distributed electric propeller slipstream wing lift measurement device to build a propeller and wing aerodynamic coupling test device. Compared with computational fluid dynamics methods, it can more accurately obtain the lift increment of the propeller slipstream on the wing, and compared with wind tunnel tests, it can quickly and cheaply obtain a large amount of effective data.

[0009] To address the aforementioned technical problems, this invention provides a distributed electric propeller slipstream wing lift measurement device, comprising a base, a free-flow power mechanism and a forward / backward moving mechanism mounted on the base, a lifting mechanism mounted on the forward / backward moving mechanism, a measuring mechanism mounted on the lifting mechanism, and an angle-of-attack adjustment mechanism mounted on the measuring mechanism. The angle-of-attack adjustment mechanism is used to fix the wing to be tested. The free-flow power mechanism includes a rectifier plate and a free-flow propeller driven by a brushless motor. Multiple free-flow propellers are arranged separately along a straight line, and the power output direction of the multiple free-flow propellers is towards the rectifier plate. The forward / backward moving mechanism... The mechanism and multiple free-flow propellers are respectively located on opposite sides of the fairing plate. The forward and backward moving mechanism is used to adjust the distance between the wing and the fairing plate. The lifting mechanism is used to adjust the placement height of the wing. The measuring mechanism includes a flange linear bearing, a flange column, and a force sensor. The flange linear bearing is connected and fixed to the lifting mechanism. The flange column is installed in the flange linear bearing in a vertically movable manner, and the flange column is connected and fixed to the angle of attack adjustment mechanism. The force sensor is connected to the flange column and is used to monitor the force on the wing. The angle of attack adjustment mechanism is used to adjust the placement angle of the wing.

[0010] In one embodiment, the free-flow power mechanism further includes guide rails and support frames; multiple guide rails are arranged separately along a straight line and are connected and fixed to the base; multiple support frames are each equipped with a free-flow propeller, multiple support frames are each connected and fixed to the rectifier plate, multiple support frames are slidably mounted on multiple guide rails, and the multiple support frames and multiple guide rails are all position-fixable structures.

[0011] In one embodiment, the forward and backward moving mechanism includes forward and backward guide rails and a sliding seat. The forward and backward guide rails are connected and fixed to the base, and the sliding seat is slidably mounted on the forward and backward guide rails. The sliding seat is provided with the lifting mechanism.

[0012] In one embodiment, the lifting mechanism is a lifting frame.

[0013] In one embodiment, the measuring mechanism further includes a lower base plate and an upper base plate; the lower base plate is connected and fixed to the lifting mechanism; the upper base plate is disposed above the lower base plate, the upper base plate has a through hole through which it passes, the measuring mechanism is disposed on the upper surface of the upper base plate, the flange column passes through the through hole and is connected to the force sensor, and the force sensor is disposed on the upper base plate.

[0014] In one embodiment, the upper base plate and the lower base plate are rotatably connected with a fixed rotation angle, and the rotation axis of the upper base plate is perpendicular to the rotation axis of the angle of attack adjustment mechanism.

[0015] In one embodiment, a first rotating shaft is provided on one side of the opposing surfaces of the upper base plate and the lower base plate for rotatable connection, and a waist hole is provided on the opposite side of the upper base plate; a screw is provided on the opposite side of the lower base plate, the screw passes through the waist hole, and an upper nut and a lower nut are threaded onto the screw, the upper nut and the lower nut being respectively placed above and below the upper base plate.

[0016] In one embodiment, the angle of attack adjustment mechanism includes an upper base plate and a lower base plate; the upper base plate is placed above the lower base plate, and the upper base plate and the lower base plate are rotatably connected by a second rotating shaft. The second rotating shaft is fitted with a bushing, and the bushing is connected and fixed to the lower base plate. The bushing has a threaded hole through its outer wall, and the threaded hole is used to screw in a bolt to lock the rotation position of the second rotating shaft.

[0017] In one embodiment, the top surface of the upper substrate is provided with an upper clamping block and a lower clamping block, and the surfaces of the upper clamping block and the lower clamping block facing each other are provided with arc-shaped grooves; the upper clamping block is located above the lower clamping block, and the upper clamping block and the lower clamping block are connected by bolts; the lower clamping block is connected and fixed to the upper substrate.

[0018] The beneficial effects of this invention are as follows:

[0019] 1. Compared with computational fluid dynamics methods, this invention can quickly and accurately obtain the lift change of a distributed electric propulsion wing under slipstream action;

[0020] 2. Compared with wind tunnel experiments, this invention is inexpensive, has low experimental costs, low energy consumption, high efficiency, and can quickly acquire a large amount of data;

[0021] 3. Compared with ordinary aerodynamic experimental devices, the present invention is low in cost, has fewer restrictions on the size of the tested object, and obtains more reliable data. Attached Figure Description

[0022] To more clearly illustrate the technical solution of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the structure provided in an embodiment of the present invention;

[0024] Figure 2 yes Figure 1 A magnified structural diagram of part A;

[0025] Figure 3 yes Figure 1 A schematic diagram of the side view structure;

[0026] Figure 4 yes Figure 1 A schematic diagram of the rear view structure;

[0027] Figure 5 yes Figure 4 A schematic diagram of the enlarged structure of part B;

[0028] Figure 6 yes Figure 4 A schematic diagram of the enlarged structure of part C;

[0029] Figure 7 This is a graph showing experimental data from different incoming flows;

[0030] Figure 8 This is an experimental diagram showing the change in the distance between the wing leading edge and the propeller;

[0031] Figure 9 This is a graph from a speed comparison experiment.

[0032] The attached figures are labeled as follows:

[0033] 10. Base;

[0034] 20. Free-flow power mechanism; 21. Flow rectifier; 22. Free-flow propeller; 23. Guide rail; 24. Support frame;

[0035] 30. Forward and backward moving mechanism; 31. Forward and backward guide rails; 32. Sliding seat;

[0036] 40. Lifting mechanism;

[0037] 50. Measuring mechanism; 51. Flange linear bearing; 52. Flange column; 53. Force sensor; 54. Lower base plate; 55. Upper base plate; 551. Through hole; 552. Waist hole; 56. First rotating shaft; 57. Screw; 58. Upper nut; 59. Lower nut;

[0038] 60. Angle of attack adjustment mechanism; 61. Upper base plate; 62. Lower base plate; 63. Second rotating shaft; 64. Bushing; 641. Threaded hole; 65. Upper clamping block; 66. Lower clamping block; 67. Arc groove;

[0039] 70. Wings. Detailed Implementation

[0040] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0041] This invention provides a lift measurement device for a distributed electric propeller slipstream wing 70, the implementation of which is as follows: Figures 1 to 6 As shown, the device includes a base 10, a free-flow power mechanism 20 and a forward / backward moving mechanism 30 mounted on the base 10, a lifting mechanism 40 mounted on the forward / backward moving mechanism 30, a measuring mechanism 50 mounted on the lifting mechanism 40, and an angle-of-attack adjustment mechanism 60 mounted on the measuring mechanism 50. The angle-of-attack adjustment mechanism 60 is used to fix the wing 70 to be tested. The free-flow power mechanism 20 includes a rectifier plate 21 and free-flow propellers 22 driven by a brushless motor. Multiple free-flow propellers 22 are arranged separately along a straight line, and the power output direction of the multiple free-flow propellers 22 is all towards the rectifier plate 21. The forward / backward moving mechanism 30 and the multiple free-flow propellers 22... 2 are respectively located on opposite sides of the fairing plate 21. The forward and backward moving mechanism 30 is used to adjust the distance between the wing 70 and the fairing plate 21; the lifting mechanism 40 is used to adjust the placement height of the wing 70; the measuring mechanism 50 includes a flange linear bearing 51, a flange column 52 and a force sensor 53; the flange linear bearing 51 is connected and fixed to the lifting mechanism 40; the flange column 52 is installed in the flange linear bearing 51 in a way that allows it to move up and down, and the flange column 52 is connected and fixed to the angle of attack adjustment mechanism 60; the force sensor 53 is connected to the flange column 52, and the force sensor 53 is used to monitor the force on the wing 70; the angle of attack adjustment mechanism 60 is used to adjust the placement angle of the wing 70.

[0042] In application, the wing 70 to be tested is fixed on the angle of attack adjustment mechanism 60. The angle of attack adjustment mechanism 60 can be rotated to adjust the placement angle of the wing 70. The lifting mechanism 40 can adjust the placement height of the wing 70. The forward and backward moving mechanism 30 is used to adjust the distance between the wing 70 and the fairing plate 21. Therefore, the free flow dynamic mechanism 20 can be used to generate the incoming flow to realize the environmental simulation under various conditions. Then, the force condition of the wing 70 can be monitored by the measuring mechanism 50.

[0043] Specifically, when the wing 70 is affected by the incoming flow force, the wing 70 will generate corresponding lifting and lowering motion. Therefore, the wing 70 will drive the flange column 52 to lift and lower. The lifting and lowering motion of the flange column 52 will generate different forces on the force sensor 53, thereby realizing the force monitoring of the wing 70.

[0044] For example, in Figure 7 The image shows experiments demonstrating the changes in lift and angle of attack of the wing 70 under two different operating conditions using the device of this invention; Figure 8 The image shows an experiment demonstrating the change in lift of the wing 70 and the distance from the leading edge of the wing 70 to the rotor disk, conducted using the device of this invention. Figure 9 The image shows a comparison experiment between the slipstream velocity and the incoming flow velocity completed using the device of the present invention; clearly, the present invention has passed the experiment and a prototype has been developed, with very ideal results.

[0045] By adopting the above settings, at least the following beneficial effects can be achieved:

[0046] 1. Compared with computational fluid dynamics methods, this invention can quickly and accurately obtain the lift change of a distributed electric propulsion wing 70 under slipstream action;

[0047] 2. Compared with wind tunnel experiments, this invention is inexpensive, has low experimental costs, low energy consumption, high efficiency, and can quickly acquire a large amount of data;

[0048] 3. Compared with ordinary aerodynamic experimental devices, the present invention is low in cost, has fewer restrictions on the size of the tested object, and obtains more reliable data.

[0049] like Figure 1 and Figure 2 As shown, in this embodiment, the free-flow power mechanism 20 is preferably provided to include guide rails 23 and support frames 24; multiple guide rails 23 are arranged separately along a straight line and are connected and fixed to the base 10; multiple support frames 24 are provided with free-flow propellers 22, multiple support frames 24 are connected and fixed to the rectifier plate 21, multiple support frames 24 are slidably installed on multiple guide rails 23, and the multiple support frames 24 and multiple guide rails 23 are all position-fixable structures.

[0050] With this setup, the position of the free-flow propeller 22 can be adjusted. For example, the support frame 24 can slide on the guide rail 23. After sliding to the appropriate position, the position between the support frame 24 and the guide rail 23 can be locked with bolts, thereby increasing the number of simulable experimental situations.

[0051] like Figure 1 and Figure 3 As shown, this embodiment preferably includes a front and rear moving mechanism 30 comprising a front and rear guide rail 31 and a sliding seat 32. The front and rear guide rail 31 is connected and fixed to the base 10, and the sliding seat 32 is slidably mounted on the front and rear guide rail 31. A lifting mechanism 40 is provided on the sliding seat 32.

[0052] With this configuration, the movement function of the forward and backward moving mechanism 30 is realized by the movement of the sliding seat 32 on the forward and backward guide rails 31.

[0053] like Figure 3 As shown, in this embodiment, the lifting mechanism 40 is preferably set as a lifting frame.

[0054] With this setup, the lifting mechanism 40 is lifted using the lifting frame.

[0055] like Figures 3 to 5 As shown, in this preferred embodiment, the measuring mechanism 50 also includes a lower base plate 54 and an upper base plate 55; the lower base plate 54 is connected and fixed to the lifting mechanism 40; the upper base plate 55 is located above the lower base plate 54, and the upper base plate 55 has a through hole 551 through which it passes. The measuring mechanism 50 is located on the upper surface of the upper base plate 55, and the flange column 52 passes through the through hole 551 and is connected to the force sensor 53. The force sensor 53 is located on the upper base plate 55.

[0056] By adopting this configuration, the flange post 52 is connected to the force sensor 53, thereby ensuring the accuracy of force monitoring of the wing 70.

[0057] like Figures 3 to 5 As shown, in this embodiment, the upper base plate 55 and the lower base plate 54 are preferably connected by a rotatable connection with a fixed rotation angle, and the rotation axis of the upper base plate 55 is perpendicular to the rotation axis of the angle of attack adjustment mechanism 60.

[0058] By adopting this setting, the wing 70 can be adjusted in two directions, thus meeting the simulation requirements in more situations.

[0059] like Figures 3 to 5As shown, in this embodiment, a first rotating shaft 56 is provided on one side of the opposing surfaces of the upper base plate 55 and the lower base plate 54 for rotatable connection, and a waist hole 552 is provided on the opposite side of the upper base plate 55; a screw 57 is provided on the opposite side of the lower base plate 54, the screw 57 passes through the waist hole 552, and an upper nut 58 and a lower nut 59 are threadedly connected to the screw 57, with the upper nut 58 and the lower nut 59 respectively positioned above and below the upper base plate 55.

[0060] After adopting this setting method, simply loosen the upper nut 58 and the lower nut 59 to facilitate the rotation of the upper base plate 55, thereby adjusting the placement angle and height of the wing 70 in this direction. After adjusting to the desired position, tighten the upper nut 58 and the lower nut 59 to fix the current position of the upper base plate 55.

[0061] like Figure 3 , Figure 4 and Figure 6 As shown, this embodiment preferably includes an angle-of-attack adjustment mechanism 60 comprising an upper substrate 61 and a lower substrate 62. The upper substrate 61 is positioned above the lower substrate 62, and the upper substrate 61 and the lower substrate 62 are rotatably connected by a second rotating shaft 63. The second rotating shaft 63 is fitted with a bushing 64, which is fixedly connected to the lower substrate 62. The bushing 64 is provided with a threaded hole 641 through which its outer wall passes, and the threaded hole 641 is used to screw in a bolt to lock the rotation position of the second rotating shaft 63.

[0062] After adopting this setting, if the bolt is not tightened in the threaded hole 641, the second rotating shaft 63 will be in a state where it can rotate freely. Therefore, the placement angle of the wing 70 can be adjusted. After adjusting to the required position, the bolt is then tightened in the threaded hole 641 to lock the position of the second rotating shaft 63.

[0063] like Figure 3 , Figure 4 and Figure 6 As shown, in this embodiment, the top surface of the upper substrate 61 is preferably provided with an upper clamping block 65 and a lower clamping block 66. The surfaces of the upper clamping block 65 and the lower clamping block 66 facing each other are provided with arc-shaped grooves 67. The upper clamping block 65 is located above the lower clamping block 66, and the upper clamping block 65 and the lower clamping block 66 are connected by bolts. The lower clamping block 66 is connected and fixed to the upper substrate 61.

[0064] After adopting this setting method, simply loosen the bolts between the upper clamping block 65 and the lower clamping block 66 to allow the upper clamping block 65 to move up and down so that the wing 70 can be placed in the arc-shaped groove 67 of both the upper clamping block 65 and the lower clamping block 66. After the wing 70 is placed, tighten the bolts between the upper clamping block 65 and the lower clamping block 66 to fix the wing 70.

[0065] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A distributed electric propulsion propeller slipstream wing lift measurement device, characterized in that, It includes a base, a free-flowing power mechanism and a forward and backward moving mechanism disposed on the base, a lifting mechanism disposed on the forward and backward moving mechanism, a measuring mechanism disposed on the lifting mechanism, and an angle-of-attack adjustment mechanism disposed on the measuring mechanism, wherein the angle-of-attack adjustment mechanism is used to fix the wing to be tested; The free-flow power mechanism includes a rectifier plate and a free-flow propeller driven by a brushless motor. Multiple free-flow propellers are arranged separately along a straight line, and the power output direction of multiple free-flow propellers is towards the rectifier plate. The free-flow power mechanism also includes a guide rail and a support frame; Multiple guide rails are arranged separately along a straight line and are connected and fixed to the base; Each of the multiple support frames is equipped with a free-flow propeller, each of the multiple support frames is connected and fixed to the rectifier plate, each of the multiple support frames is slidably installed on multiple guide rails, and the multiple support frames and the multiple guide rails are all position-fixable structures; The forward and backward moving mechanism and the plurality of free-flow propellers are respectively disposed on opposite sides of the fairing plate. The forward and backward moving mechanism is used to adjust the distance between the wing and the fairing plate. The lifting mechanism is used to adjust the placement height of the wings; The measuring mechanism includes a flange linear bearing, a flange column, and a force sensor; the flange linear bearing is fixedly connected to the lifting mechanism; the flange column is installed inside the flange linear bearing in a way that allows it to move up and down, and the flange column is fixedly connected to the angle of attack adjustment mechanism; the force sensor is connected to the flange column, and the force sensor is used to monitor the force on the wing; The measuring mechanism also includes a lower base plate and an upper base plate; The lower base plate is connected and fixed to the lifting mechanism; The upper base plate is located above the lower base plate. The upper base plate has a through hole through which it passes. The flange column passes through the through hole and is connected to the force sensor. The force sensor is located on the upper base plate. The angle-of-attack adjustment mechanism is used to adjust the placement angle of the wing; The angle-of-attack adjustment mechanism includes an upper base plate and a lower base plate; The upper substrate is placed above the lower substrate. The upper substrate and the lower substrate are rotatably connected by a second rotating shaft. The second rotating shaft is fitted with a bushing. The bushing is connected and fixed to the lower substrate. The bushing has a threaded hole that penetrates its outer wall. The threaded hole is used to screw in a bolt to lock the rotation position of the second rotating shaft.

2. The distributed electric propulsion propeller slipstream wing lift measurement device according to claim 1, characterized in that, The forward and backward moving mechanism includes forward and backward guide rails and a sliding seat. The forward and backward guide rails are connected and fixed to the base. The sliding seat is slidably installed on the forward and backward guide rails, and the lifting mechanism is provided on the sliding seat.

3. The distributed electric propulsion propeller slipstream wing lift measurement device according to claim 1, characterized in that, The lifting mechanism is a lifting frame.

4. The distributed electric propulsion propeller slipstream wing lift measurement device according to claim 1, characterized in that, The upper base plate and the lower base plate are connected by a rotatable connection with a fixed rotation angle, and the rotation axis of the upper base plate is perpendicular to the rotation axis of the angle of attack adjustment mechanism.

5. The distributed electric propulsion propeller slipstream wing lift measurement device according to claim 4, characterized in that, The upper base plate and the lower base plate are rotatably connected on one side of their opposing surfaces via a first rotating shaft, and the other side of the upper base plate is provided with a waist hole; A screw is provided on the opposite side of the lower base plate. The screw passes through the waist hole and is threaded with an upper nut and a lower nut. The upper nut and the lower nut are respectively placed above and below the upper base plate.

6. The distributed electric propulsion propeller slipstream wing lift measurement device according to claim 1, characterized in that, The top surface of the upper substrate is provided with an upper clamping block and a lower clamping block, and the surfaces of the upper clamping block and the lower clamping block facing each other are provided with arc-shaped grooves; The upper clamping block is located above the lower clamping block, and the upper clamping block and the lower clamping block are connected by bolts. The lower clamping block is connected and fixed to the upper substrate.

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