A multi-fan open wind tunnel for simulating variable-angle inflow

Abstract

The present invention discloses a multi-fan open wind tunnel for simulating variable-angle incoming flow, comprising a three-degree-of-freedom platform, a fan assembly mechanism for simulating a wind tunnel is arranged at the upper end of the three-degree-of-freedom platform, and a slide rail adjustment mechanism for adjusting the air outlet form of the fan assembly mechanism is arranged between the three-degree-of-freedom platform and the fan assembly mechanism. The present invention has good use effect, and a complex incoming flow with a variable angle is formed by adjusting the three-degree-of-freedom platform, the position of the slide rail, and the speed of the fan, thereby simulating the incoming flow of the wind field that fits the real flight environment of the aircraft, and at the same time, the structure is reliable, simple, and easy to manufacture.

Description

Technical Field

[0001] The invention relates to the technical field of wind tunnels, in particular to a multi-fan open wind tunnel that simulates variable-angle incoming flow. Background Art

[0002] With the maturity and development of wind tunnel experimental technology, wind tunnel devices are now widely used in the aerodynamic performance and flow field characteristics testing of aircraft. Conventional reflow wind tunnel equipment generally uses a single large fan as a power source and forms a uniform flow in the test section, which can simulate the ideal uniform wind field environment for aircraft operation to a certain extent, but the simulation ability for other more complex wind field flows is limited. Currently, the active control wind tunnel using a multi-fan array as a drive is a more advanced wind field simulation technology. The multi-fan active control turbulence wind tunnel of Miyazaki University in Japan changes the speed and phase of each fan through electrical signals to generate the required airflow. The multi-fan wind tunnel of Shanghai Jiaotong University can simulate the wind speed profile law of the atmospheric boundary layer, and the multi-fan array wind tunnel of Tongji University can also simulate pulsating wind fields. The multi-array wind tunnel has improved the simulation ability of non-uniform wind fields.

[0003] However, the structural design ideas of these wind tunnels are still basically consistent with conventional wind tunnels, retaining the direct-flow test section structure and relatively complex inlet and outlet pipes. The volume structure is large and complex, and the construction cost is high. In addition, once the design and construction are completed, the fan array is fixed, and the incoming flow method can only flow along the designed channel direction, lacking the ability to simulate wind fields with vertical or lateral velocity components. Summary of the invention

[0004] The object of the present invention is to provide a multi-fan open wind tunnel simulating variable-angle incoming flow to solve the problems raised in the above-mentioned background technology.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solutions: a multi-fan open wind tunnel simulating variable-angle incoming flow, comprising a three-degree-of-freedom platform, a fan assembly mechanism for simulating a wind tunnel is arranged at the upper end of the three-degree-of-freedom platform, and a slide rail adjustment mechanism for adjusting the air outlet form of the fan assembly mechanism is arranged between the three-degree-of-freedom platform and the fan assembly mechanism.

[0006] Preferably, the three-degree-of-freedom platform includes a base plate, anchor bolts, an air pump, a lower hinge seat, a lower hinge fixing bolt, a hinge component, a sleeve, a telescopic rod, a top plate, an upper hinge seat, and an upper hinge fixing bolt. A plurality of anchor bolts are evenly fixedly arranged around the outer surface of the lower end of the base plate, and the base plate can be fixed to the ground or the end face of a fixed device by means of the anchor bolts. A plurality of air pumps are evenly fixedly arranged on the upper surface of the base plate. There are three air pumps, which are arranged at an interval of 120 degrees on the upper end of the base plate. A lower hinge seat is fixedly arranged on one side of the air pump on the upper end of the base plate, a lower hinge fixing bolt is fixedly arranged between the lower hinge seat and the base plate, a top plate is arranged on the upper end of the base plate, a plurality of upper hinge seats are evenly fixedly arranged on the lower surface of the base plate, an upper hinge fixing bolt is fixedly arranged between the upper hinge seat and the top plate, and the lower hinge The seat and the upper hinge seat are both movably provided with hinge parts, the surface of the hinge part at the lower end is provided with a sleeve, and the surface of the hinge part at the upper end is provided with a telescopic rod, the telescopic rod is movably inserted into the sleeve, the hinge part is movably provided inside the lower hinge seat and the upper hinge seat, and the sleeve and the telescopic rod are movably connected, so that the sleeve and the telescopic rod can be rotated in multiple directions, thereby facilitating the subsequent extension and retraction of the telescopic rod, so that the top plate can produce relative rotation along the three coordinate axes of the orthogonal coordinate system within a certain range, thereby changing the posture of the top plate relative to the bottom plate, the sleeve is hollow inside, and the air pump corresponds to the sleeves near it one by one, and the corresponding air pump is connected to the inside of the hollow sleeve through a pipeline, so that gas can be pumped into the sleeve, thereby making the telescopic rod at the upper end of the sleeve extend or shorten.

[0007] Preferably, the slide rail adjustment mechanism includes slide rails and sliders, a plurality of slide rails are evenly fixed on the outer surface of the upper end of the top plate, a slider is movably engaged with the outer surface of the upper end of the slide rails through a slide groove, the slide rails are fixed to the upper end of the top plate by bolts, and a plurality of positioning holes for fixing the slide rails are provided on the upper end of the top plate. When the fixed slide rails are parallel to each other, the fan row installed at the upper end can generate uniform straight flows parallel to each other; when the installed slide rails are not parallel to form an arc, the fan row can generate a fan-shaped flow; the slider can slide freely within the limit positions at both ends of the slide rails, and fan rows with different curvature radii are formed according to the scales on the slide rails; when the screws on the surface of the locking slider are tightened, the slider can be locked.

[0008] Preferably, the fan assembly mechanism includes fan units, fasteners, and locking screws. A plurality of fan units are evenly fixed on the upper end of the slider, fasteners are fixed between the fan units, and locking screws are fixed between the fan units and the fasteners. The fan assembly mechanism can be used to quickly and conveniently assemble any number of fan units as needed to form a fan array of a target size, which is convenient for conducting wind tunnel tests.

[0009] Preferably, the hinge component at the lower end is movably connected to the lower hinge seat through a rotating shaft, and the hinge component at the lower end is movably connected to the sleeve through a rotating shaft, and the rotating shaft where the sleeve is located and the rotating shaft connected to the lower hinge component and the lower hinge seat are perpendicular to each other. The specific connection form can be as follows: Figure 1 It is expressed that the sleeve can rotate in multiple directions relative to the lower hinge seat.

[0010] Preferably, the upper hinge component is movably connected to the upper hinge seat via a rotating shaft, and the upper hinge component is movably connected to the telescopic rod via a rotating shaft, and the rotating shaft where the telescopic rod is located is perpendicular to the rotating shaft connecting the upper hinge component and the upper hinge seat, so that the telescopic rod can rotate in multiple directions relative to the upper hinge seat.

[0011] Compared with the prior art, the present invention has the following beneficial effects:

[0012] 1. The present invention can simulate plane and fan-shaped incoming flows and adjust the spatial angle of the incoming flow by changing the posture of the three-degree-of-freedom platform and the relative position of the slide rail; at the same time, by controlling the different speeds of the fan units, the velocity gradient between airflow layers is simulated. The wind tunnel can simulate different types of incoming flows and can achieve a wind field environment that is more in line with the actual flight environment of the aircraft than the prior art.

[0013] 2. The present invention has a simple structure and uses a simple mechanical mechanism to simulate a wind tunnel. It has a simple structure and eliminates the need for complex wind tunnel piping. It is easy to manufacture, improve, operate and control, and is easy to promote and use. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a schematic diagram of the overall structure of a multi-fan open wind tunnel for simulating variable-angle incoming flow according to the present invention;

[0015] Figure 2 This is a top view of the overall structure of a multi-fan open wind tunnel simulating variable-angle incoming flow according to the present invention;

[0016] Figure 3 A horizontal arrangement view of a multi-fan open wind tunnel slide rail for simulating variable-angle incoming flow according to the present invention;

[0017] Figure 4 This is an overall structural view of a multi-fan open wind tunnel slide rail adjustment mechanism for simulating variable-angle incoming flow according to the present invention.

[0018] In the figure: 1. fan assembly mechanism; 101. fan unit; 102. fastener; 103. locking screw; 2. three-degree-of-freedom platform; 201. base plate; 202. anchor bolt; 203. air pump; 204. lower hinge seat; 205. lower hinge fixing bolt; 206. hinge component; 207. sleeve; 208. telescopic rod; 209. top plate; 210. upper hinge seat; 211. upper hinge fixing bolt; 3. slide rail adjustment mechanism; 301. slide rail; 302. slider. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] See also Figure 1-4 The present invention provides a technical solution: a multi-fan open wind tunnel simulating variable-angle incoming flow, comprising a three-degree-of-freedom platform 2, a fan assembly mechanism 1 for simulating a wind tunnel is arranged on the upper end of the three-degree-of-freedom platform 2, and a slide rail adjustment mechanism 3 for adjusting the air outlet form of the fan assembly mechanism 1 is arranged between the three-degree-of-freedom platform 2 and the fan assembly mechanism 1.

[0021] The three-degree-of-freedom platform 2 includes a base plate 201, anchor bolts 202, an air pump 203, a lower hinge seat 204, a lower hinge fixing bolt 205, a hinge component 206, a sleeve 207, a telescopic rod 208, a top plate 209, an upper hinge seat 210, and an upper hinge fixing bolt 211. A plurality of anchor bolts 202 are evenly fixedly arranged around the outer surface of the lower end of the base plate 201. The base plate 201 can be fixed to the ground or the end face of a fixed device through the anchor bolts 202. The upper surface of the base plate 201 is evenly fixedly arranged with a plurality of anchor bolts 202. Dry air pump 203, three air pumps 203 are provided, which are arranged at an interval of 120 degrees on the upper end of the bottom plate 201, and a lower hinge seat 204 is fixedly provided on the upper end of the bottom plate 201 on one side of the air pump 203, and a lower hinge fixing bolt 205 is fixedly provided between the lower hinge seat 204 and the bottom plate 201, and a top plate 209 is provided on the upper end of the bottom plate 201, and a plurality of upper hinge seats 210 are evenly fixedly provided on the lower end surface of the bottom plate 201, and an upper hinge fixing bolt 211 is fixedly provided between the upper hinge seat 210 and the top plate 209, The lower hinge seat 204 and the upper hinge seat 210 are both movably provided with a hinge component 206, the surface of the lower hinge component 206 is provided with a sleeve 207, and the surface of the upper hinge component 206 is provided with a telescopic rod 208, and the telescopic rod 208 is movably inserted in the sleeve 207. The hinge component 206 is movably provided in the lower hinge seat 204 and the upper hinge seat 210, and the sleeve 207 and the telescopic rod 208 are movably connected, so that the sleeve 207 and the telescopic rod 208 can be moved in multiple directions. Rotation can facilitate the subsequent extension and retraction of the telescopic rod 208, so that the top plate 209 can generate relative rotation along the three coordinate axes of the orthogonal coordinate system within a certain range, thereby changing the posture of the top plate 209 relative to the bottom plate 201. The sleeve 207 is hollow inside, and the air pump 203 corresponds to the sleeve 207 near it one by one. The corresponding air pump 203 is connected to the interior of the hollow sleeve 207 through a pipeline, so that gas can be pumped into the sleeve 207, so that the telescopic rod 208 at the upper end of the sleeve 207 can be extended or shortened.

[0022] The slide rail adjustment mechanism 3 includes a slide rail 301 and a slider 302. A plurality of slide rails 301 are evenly fixed on the outer surface of the upper end of the top plate 209. The slider 302 is movably engaged with the upper outer surface of the slide rail 301 through a slide groove. The slide rail 301 is fixed to the upper end of the top plate 209 by bolts. The upper end of the top plate 209 is provided with a plurality of positioning holes for fixing the slide rail 301. When the fixed slide rails 301 are parallel to each other, the fan array installed at the upper end can generate parallel uniform straight flows. When the installed slide rails 301 are not parallel to form an arc, the fan array can generate a fan-shaped flow. The slider 302 can slide freely within the limit positions at both ends of the slide rail 301 to form a fan array with different curvature radii according to the scales on the slide rail 301. When the screws on the surface of the locking slider 302 are tightened, the slider 302 can be locked.

[0023] The fan assembly mechanism 1 includes a fan unit 101, a fastener 102, and a locking screw 103. A plurality of fan units 101 are evenly fixedly arranged on the upper end of the slider 302. The fasteners 102 are fixedly arranged between the fan units 101. The locking screws 103 are fixedly arranged between the fan units 101 and the fasteners 102. The fan assembly mechanism 1 can be used to quickly and conveniently assemble any number of fan units 101 as needed to form a fan array of a target size, which is convenient for conducting wind tunnel tests.

[0024] The hinge member 206 at the lower end is movably connected to the lower hinge seat 204 through the rotating shaft, and the hinge member 206 at the lower end is movably connected to the sleeve 207 through the rotating shaft. The rotating shaft where the sleeve 207 is located is perpendicular to the rotating shaft connecting the lower hinge member 206 and the lower hinge seat 204. The specific connection form can be as follows: Figure 1 As shown in FIG. 2 , the sleeve 207 can rotate in multiple directions relative to the lower hinge seat 204 .

[0025] The upper hinge component 206 is movably connected to the upper hinge seat 210 via a rotating shaft, and the upper hinge component 206 is movably connected to the telescopic rod 208 via a rotating shaft. The rotating shaft where the telescopic rod 208 is located is perpendicular to the rotating shaft connecting the upper hinge component 206 and the upper hinge seat 204, so that the telescopic rod 208 can rotate in multiple directions relative to the upper hinge seat 210.

[0026] Working principle: This test device is installed on the fixed ground end or the fixed horizontal end through the anchor bolts 202. The fan unit 101 is installed on the upper end of the three-degree-of-freedom platform 2 through the slide rail 301 and the slider 302. The fan unit 101 rotates to provide airflow to simulate the wind field for testing the test device. The expected attitude value is input by the computer. After attitude solution, the pressure value required by the sleeve 207 is transmitted to the single-chip microcomputer via the data line. The single-chip microcomputer is then used to directly control the air pressure of the air pump 203. At the same time, it is used to collect the signal of the air pump 203 and send the speed signal of the fan unit 101, and transmit it back to the computer host computer to calculate its actual attitude for correction. The single-chip microcomputer lower computer is connected to the computer host computer by a serial port. When the device is used, the air pump 203 can be started. The air pressure generated when the air pump 203 is started pushes the three telescopic rods 208 on the bottom plate 201, so that the telescopic rods 208 extend different lengths inside the sleeve 207. The change in the length of the telescopic rods 208 makes the attitude of the top plate 209 relatively The bottom plate 201 changes, so that the slide rail 301 on the top plate 209 and the fan unit 101 array produce corresponding attitude angles, thereby generating an incoming flow with an attitude angle relative to the ground. When the device is used, the parallelism of the slide rail 301 can be adjusted as needed. When the fixed slide rails 301 are parallel to each other, the fan array installed at the upper end can generate a uniform straight incoming flow that is parallel to each other. When the installed slide rails 301 are not parallel to form an arc, the fan array can generate a fan-shaped incoming flow. The slider 302 can slide freely within the limit positions at both ends of the slide rail 301, and fan arrays with different curvature radii are formed according to the scales on the slide rail 301. In this way, different speed gradients are generated by different speeds of different fan units 101, and different attitude angles are formed by the inclination of the top plate 209, so that the device simulates different flow states such as non-uniform incoming flow, side wind, shear wind, and near-ground boundary layer wind field, effectively improving the use effect of the device. This is the working principle of a multi-fan open wind tunnel simulating variable-angle incoming flow according to the present invention.

[0027] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0028] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A multi-fan open wind tunnel for simulating variable-angle incoming flow, comprising a three-degree-of-freedom platform (2), characterized in that: A fan assembly mechanism (1) for simulating a wind tunnel is arranged at the upper end of the three-degree-of-freedom platform (2), and a slide rail adjustment mechanism (3) for adjusting the air outlet form of the fan assembly mechanism (1) is arranged between the three-degree-of-freedom platform (2) and the fan assembly mechanism (1).

2. A multi-fan open wind tunnel for simulating variable-angle incoming flow according to claim 1, characterized in that: The three-degree-of-freedom platform (2) comprises a base plate (201), anchor bolts (202), an air pump (203), a lower hinge seat (204), a lower hinge fixing bolt (205), a hinge component (206), a sleeve (207), a telescopic rod (208), a top plate (209), an upper hinge seat (210), and an upper hinge fixing bolt (211); a plurality of anchor bolts (202) are evenly fixedly arranged around the outer surface of the lower end of the base plate (201); a plurality of air pumps (203) are evenly fixedly arranged on the upper surface of the base plate (201); a lower hinge seat (204) is fixedly arranged on one side of the air pump (203) at the upper end of the base plate (201); and a hinge is formed between the lower hinge seat (204) and the base plate (201). A lower hinge fixing bolt (205) is fixedly arranged, a top plate (209) is arranged at the upper end of the bottom plate (201), a plurality of upper hinge seats (210) are evenly and fixedly arranged on the lower end surface of the bottom plate (201), an upper hinge fixing bolt (211) is fixedly arranged between the upper hinge seat (210) and the top plate (209), hinge components (206) are movably arranged inside the lower hinge seat (204) and the upper hinge seat (210), a sleeve (207) is arranged on the surface of the hinge component (206) at the lower end, and a telescopic rod (208) is arranged on the surface of the hinge component (206) at the upper end, the telescopic rod (208) is movably inserted into the sleeve (207), and the sleeve (207) is hollow inside.

3. A multi-fan open wind tunnel for simulating variable-angle incoming flow according to claim 2, characterized in that: The slide rail adjustment mechanism (3) comprises a slide rail (301) and a slider (302); a plurality of slide rails (301) are evenly and fixedly arranged on the outer surface of the upper end of the top plate (209); and a slider (302) is movably engaged with the upper outer surface of the slide rail (301) through a slide groove.

4. A multi-fan open wind tunnel for simulating variable-angle incoming flow according to claim 3, characterized in that: The fan assembly mechanism (1) comprises a fan unit (101), a fastener (102), and a locking screw (103); a plurality of fan units (101) are evenly fixedly arranged on the upper end of the slider (302); fasteners (102) are fixedly arranged between the fan units (101); and locking screws (103) are fixedly arranged between the fan unit (101) and the fastener (102).

5. The multi-fan open wind tunnel for simulating variable-angle incoming flow according to claim 2, characterized in that: The hinge component (206) at the lower end is movably connected to the lower hinge seat (204) via a rotating shaft, and the hinge component (206) is movably connected to the sleeve (207) via a rotating shaft.

6. The multi-fan open wind tunnel for simulating variable-angle incoming flow according to claim 2, characterized in that: The upper hinge component (206) is movably connected to the upper hinge seat (210) via a rotating shaft, and the upper hinge component (206) is movably connected to the telescopic rod (208) via a rotating shaft.

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