Power fan section of subsonic calibration device

Abstract

A power fan section of a subsonic calibration device belongs to the technical field of wind tunnel airflow control and comprises a base, an inlet expansion joint is mounted on the base, a hood cylinder is fixedly connected to the right end of the inlet expansion joint, a hood is fixedly mounted in the hood cylinder, and an inlet cylinder is fixedly connected to the right end of the hood cylinder. The right end of the inlet cylinder is fixedly connected with a tail cover cylinder, the tail cover cylinder and the inlet cylinder are both fixedly installed on the table top of the base, a water-cooling motor and a tail cover are fixedly installed in the tail cover cylinder, the output end of the water-cooling motor faces the direction of the head cover, and the output end of the water-cooling motor is sleeved with an impeller. The right end of the tail cover cylinder is fixedly connected with an outlet expansion joint, and a plurality of rotation stopping blades are fixedly installed between the inner side wall of the tail cover cylinder and the water cooling motor. Meanwhile, delay errors caused by pressure changes of the air storage tank and adjustment of the adjusting valve are avoided, power is more stably provided for the test section, and the utilization rate of the experiment duration can be effectively improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of wind tunnel air flow control, and particularly relates to a power fan section of a subsonic calibration device. Background Art

[0002] When a flying airliner operates in a subsonic state, the accuracy of the feedback data is particularly important. The accuracy calibration of the pressure and temperature detection instruments for real-time flight data is the most crucial link. In China, a subsonic wind tunnel is usually used as the experimental carrier.

[0003] A wind tunnel is a pipeline loop experimental device. The principle is to control the air flow to simulate the gas flow around an aircraft or an object. It is one of the most commonly used and effective tools for instrument calibration experiments.

[0004] The means of controlling the air flow in a wind tunnel is called the power section. In existing subsonic wind tunnels, the power section is the release of a high-pressure gas storage tank, which provides power for the system. The designed duration of the release is 10,800 seconds, and the actual usage duration is about 9,000 seconds, which can supply 2 - 3 sets of devices to complete the calibration task. The gas storage tank is refilled with 4 screw compressors, the single-machine motor power is 22 Kw / h, and the actual total power consumption is 77 Kw / h. Calculated according to the refilling process of 3.5 h, the total power consumption is 269.5 Kw. The available usage time is 2.5 h, and the actual power consumption is 107.8 Kw / h.

[0005] However, using a high-pressure gas storage tank as the power source of the wind tunnel has the following disadvantages:

[0006] 1. The power source of the wind tunnel is one of the most critical sections. When the total pressure of the gas storage tank drops to 0.2 Mpa, even if the rear regulating valve is fully opened, it cannot meet the required wind tunnel flow rate. The experiment must be suspended, and the gas storage tank needs to be energized. It cannot work continuously.

[0007] 2. During the operation of the gas storage tank, there are processes of energy charging and release, resulting in more processes and lower efficiency.

[0008] 3. The test section needs to provide stable power. When the gas storage tank is working, the pressure gradually decreases. It is necessary to intelligently control the opening degree of the regulating valve to ensure the stability of the pressure in the test section. The regulating valve requires time (although extremely short) during the working process, resulting in a time delay error.

[0009] 4. The test section needs to meet the assessments at different temperature and pressure points, and the wind tunnel needs to reach a uniform state. The gas storage tank needs to work before the experiment starts. Therefore, the designed duration is 10,800 seconds, and the actual available experimental duration is only 83.33% of the designed point. The restriction is relatively large.

[0010] 5. The regulating valve is of a conical rubber extrusion sealing structure, with zero leakage in the closed state. However, during long-term use, there is wear. During the energy charging period of the gas storage tank, the closure is not tight, resulting in damage to a large number of wind tunnel detection instruments, high maintenance costs, and long maintenance time.

[0011] To solve the above technical problems, a power fan section of a subsonic calibration device is provided to replace the existing high-pressure gas storage tank and be used as the power source of the wind tunnel. Summary of the Invention

[0012] The purpose of the present invention is to provide a power fan section of a subsonic calibration device to solve the problems raised in the above background technology. The specific technical solution is as follows:

[0013] A power fan section of a subsonic calibration device includes a base. An inlet expansion joint is installed on the base. The right end of the inlet expansion joint is fixedly connected to a head cover cylinder body. A head cover is fixedly installed inside the head cover cylinder body, and the right end of the head cover cylinder body is fixedly connected to an inlet cylinder body. The right end of the inlet cylinder body is fixedly connected to a tail cover cylinder body. Both the tail cover cylinder body and the inlet cylinder body are fixedly installed on the tabletop of the base. A water-cooled motor and a tail cover are fixedly installed inside the tail cover cylinder body. The output end of the water-cooled motor faces the direction of the head cover, and an impeller is sleeved on the output end of the water-cooled motor. The tail cover is fixedly installed on the right surface of the water-cooled motor. The right end of the tail cover cylinder body is fixedly connected to an outlet expansion joint. A plurality of anti-rotation blades are fixedly installed between the inner side wall of the tail cover cylinder body and the water-cooled motor.

[0014] In the above technical solution, the right end of the output shaft of the water-cooled motor is installed with an encoder through a coupling.

[0015] In the above technical solution, two vibration sensors are fixedly installed at the bearing base at the right end of the water-cooled motor. Both the vibration sensors and the encoder are located inside the tail cover.

[0016] In the above technical solution, the connection cables of the water-cooled motor vibration sensors and the encoder are routed through the internal channels of the corresponding anti-rotation blades and then penetrate the inlet cylinder body.

[0017] In the above technical solution, the number of assembled anti-rotation blades is twelve, and the twelve anti-rotation blades are circumferentially equidistantly arranged inside the inlet cylinder body.

[0018] In the above technical solution, an inlet pressure measuring tube and an outlet pressure measuring tube are respectively fixedly installed at the air inlet end and the gas storage end of the inlet cylinder body.

[0019] In the above technical solution, the included angle between the rotor hub shaft of the impeller and the axis of the power fan section is less than 0.5°.

[0020] In the above technical solution, the gap between the tip of the impeller and the inner side wall of the inlet cylinder body is less than 0.4 mm.

[0021] In the above technical solution, the inlet expansion joint includes an expansion joint flange A. The right end of the expansion joint flange A is fixedly installed with an expansion joint inner liner A. An expansion joint corrugation A is fixedly installed between the expansion joint inner liner A and the hood cylinder body. An expansion joint adjusting wire A is installed between the expansion joint flange A and the hood cylinder body.

[0022] In the above technical solution, the outlet expansion joint includes an expansion joint flange B. The left end of the expansion joint flange B is fixedly installed with an expansion joint inner liner B. An expansion joint corrugation B is fixedly installed between the expansion joint inner liner B and the tail hood cylinder body. An expansion joint adjusting wire B is installed between the expansion joint flange B and the tail hood cylinder body.

[0023] Compared with the prior art, the power fan section of the subsonic calibration device of the present invention has the following beneficial effects:

[0024] The power fan section of this subsonic calibration device has many significant advantages compared with using a high-pressure gas storage tank as the wind tunnel power source. It solves the problem that the prior art cannot work continuously, can avoid pausing the experiment due to the reduction of the gas storage tank pressure, reduce redundant processes such as energy charging, and thus improve work efficiency; at the same time, it avoids the delay error caused by the change of the gas storage tank pressure and the adjustment of the regulating valve, provides power for the test section more stably, and can effectively improve the utilization rate of the experiment duration; and it does not rely on the conical rubber extrusion sealing structure regulating valve that is prone to wear, reducing the maintenance cost and time for damage to the detection instrument caused by the problem of the regulating valve. In addition, its structural design is reasonable. The encoder and vibration sensor monitor the equipment status in real time. The anti-rotation blade rectifies, the piezometric tube monitors the pressure, the impeller parameters are optimized, and the expansion joint absorbs vibration displacement, comprehensively ensuring the efficient, stable and safe operation of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is an exploded structural schematic diagram of the present invention.

[0026] Figure 2 It is a structural schematic diagram after the outlet expansion joint of the present invention is installed with the inlet cylinder body.

[0027] Figure 3 It is a sectional structural schematic diagram of the present invention.

[0028] Figure 4 It is a right view structural schematic diagram of the water-cooled motor of the present invention.

[0029] Figure 5 It is a working schematic diagram of the blades of the impeller of the present invention.

[0030] Figure 6 It is a working schematic diagram of the blades of the anti-rotation blade of the present invention.

[0031] Figure 7is Figure 1 The enlarged view of the local structure at position a in

[0032] Figure 8 is Figure 1 The enlarged view of the local structure at position b in

[0033] Figure 9 is Figure 2 The enlarged view of the local structure at position c in

[0034] Figure 10 is Figure 2 The enlarged view of the local structure at position d in

[0035] Figures 1 - 10 Among them: 1. Base; 2. Inlet expansion joint; 21. Expansion joint flange A; 22. Expansion joint inner lining cylinder A; 23. Expansion joint corrugation A; 24. Expansion joint adjustment wire A; 3. Hood cylinder; 31. Hood; 32. Support piece; 4. Inlet cylinder; 41. Inlet pressure measuring tube; 42. Outlet pressure measuring tube; 5. Tail hood cylinder; 51. Tail hood; 6. Outlet expansion joint; 61. Expansion joint flange B; 62. Expansion joint inner lining cylinder B; 63. Expansion joint corrugation B; 64. Expansion joint adjustment wire B; 7. Water-cooled motor; 71. Impeller; 72. Encoder; 73. Vibration sensor; 8. Anti-rotation blade;

[0036] a. Deflection angle; Wv. Reference line; β. Baseline angle, U. Axial oncoming flow. Specific embodiments

[0037] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0038] The front, back, left, right, up and down in this embodiment are described with Figure 1 as the reference plane. Please refer to Figures 1 - 10 , the present invention provides a technical solution:

[0039] A power fan section of a subsonic calibration device, including a base 1, an inlet expansion joint 2 is installed on the base 1, the right end of the inlet expansion joint 2 is fixedly connected to a hood cylinder 3, a hood 31 is fixedly installed inside the hood cylinder 3, and the right end of the hood cylinder 3 is fixedly connected to an inlet cylinder 4. The right end of the inlet cylinder 4 is fixedly connected to a tail hood cylinder 5. Both the tail hood cylinder 5 and the inlet cylinder 4 are fixedly installed on the tabletop of the base 1. A water-cooled motor 7 and a tail hood 51 are fixedly installed inside the tail hood cylinder 5. The output end of the water-cooled motor 7 faces the direction of the hood 31, and an impeller 71 is sleeved on the output end of the water-cooled motor 7. The tail hood 51 is fixedly installed on the right surface of the water-cooled motor 7. The right end of the tail hood cylinder 5 is fixedly connected to an outlet expansion joint 6. A plurality of anti-rotation blades 8 are fixedly installed between the inner side wall of the tail hood cylinder 5 and the water-cooled motor 7. The right end of the output shaft of the water-cooled motor 7 is installed with an encoder 72 through a coupling. Two vibration sensors 73 are fixedly installed at the bearing base at the right end of the water-cooled motor 7. Both the vibration sensors 73 and the encoder 72 are located inside the tail hood 51. Both the hood 31 and the tail hood 51 are bullet-shaped, which can reduce the turbulence and energy loss of the air flow.

[0040] A plurality of support pieces 32 are fixedly installed between the hood 31 and the inlet cylinder 4, and the hood 31 is fixedly installed inside the inlet cylinder 4 through the support pieces 32.

[0041] The encoder 72 adopts an FGHJ40K-2048G-90G-NG / 20P type incremental encoder with an accuracy of 0.2%, which can ensure that the power air source remains stable during the experimental stage.

[0042] The impeller 71 is integrally made of aviation forged aluminum and is integrally machined by a five-axis linkage CNC machine tool.

[0043] The angle between the rotor hub shaft of the impeller 71 and the axis of the power fan section is less than 0.5°.

[0044] The gap between the tip of the impeller 71 and the inner side wall of the inlet cylinder 4 is less than 0.4 mm.

[0045] The number of assembled anti-rotation blades 8 is twelve, and the twelve anti-rotation blades 8 are circumferentially equidistantly arranged inside the inlet cylinder 4.

[0046] In addition, the connection cables of the water-cooled motor 7, the vibration sensors 73 and the encoder 72 all pass through the inside of the corresponding anti-rotation blades 8 and then penetrate through the inlet cylinder 4, as Figure 4 shown. The three connection cables adopt a completely symmetrical structure inside the anti-rotation blades 8, and a composite foil and a layer of polyester film are isolated between the anti-rotation blades 8 and the cables. This structure completely eliminates the interference of the cables and the cable conduits to the air flow.

[0047] In the above technical solution, an inlet pressure measuring pipe 41 and an outlet pressure measuring pipe 42 are fixedly installed at the air inlet end and the air storage end of the imported cylinder body 4 respectively. The inlet pressure measuring pipe 41 and the outlet pressure measuring pipe 42 can be used to connect external air pressure detection equipment, so as to monitor the air flow stability in the power fan section at any time.

[0048] Specifically, the inlet expansion joint 2 includes an expansion joint flange A21. The right end of the expansion joint flange A21 is fixedly installed with an expansion joint inner lining cylinder A22. An expansion joint corrugation A23 is fixedly installed between the expansion joint inner lining cylinder A22 and the hood cylinder body 3. An expansion joint adjusting wire A24 is installed between the expansion joint flange A21 and the hood cylinder body 3;

[0049] During the operation of the power fan section, when guiding the air flow into the hood cylinder body 3, the inlet expansion joint 2 can reduce the impact of the air flow on the equipment. On the other hand, the inlet expansion joint can reduce the turbulence degree of the air flow, make the air flow enter the subsequent components more stably, and provide stable air flow conditions for the precise calibration of the device.

[0050] Specifically, the outlet expansion joint 6 includes an expansion joint flange B61. The left end of the expansion joint flange B61 is fixedly installed with an expansion joint inner lining cylinder B62. An expansion joint corrugation B63 is fixedly installed between the expansion joint inner lining cylinder B62 and the tail hood cylinder body 5. An expansion joint adjusting wire B64 is installed between the expansion joint flange B61 and the tail hood cylinder body 5;

[0051] During the operation of the power fan section, the air flow pressure at the outlet may fluctuate. The expansion joint corrugation B63 of the outlet expansion joint 6 can buffer this pressure fluctuation through its own deformation, avoid damage to the subsequent pipelines or equipment caused by sudden pressure changes, and ensure the smooth discharge of the air flow from the device.

[0052] When the present invention is used as the power source of the wind tunnel, after the water-cooled motor 7 is powered on, it drives the impeller 71 to rotate to push the air to generate a subsonic air flow. The anti-rotation blades 8 eliminate the rotational component of the air flow to make it stable and uniform. The encoder 72 monitors the operating information such as the rotational speed of the water-cooled motor 7. The vibration sensor 73 detects the vibration condition of the water-cooled motor 7 to ensure stable operation. The inlet expansion joint 2 and the outlet expansion joint 6 compensate for the displacement generated by thermal expansion and contraction or other factors during the operation of the device to a certain extent, playing a role in buffering and protecting the device. Components such as the hood 31, the tail hood 51, the inlet cylinder body 4, and the tail hood cylinder body 5 jointly form the air flow channel and the protective shell of the device, ensuring that the air flow flows in the device along the predetermined path and protecting key components such as the internal water-cooled motor 7 and the impeller 71. Compared with the prior art, the present invention can work continuously and improve work efficiency; at the same time, it avoids the delay error caused by the change of the air storage tank pressure and the adjustment of the regulating valve, provides power for the test section more stably, and can effectively improve the utilization rate of the experimental time.

[0053] Combined with Figure 5As shown, the experimental parameters of the blade design of the impeller 71 during the experiment are as follows:

[0054] Blade design parameters of the impeller 71:

[0055]

[0056] Blade coordinate parameters of the impeller 71:

[0057]

[0058]

[0059]

[0060]

[0061]

[0062]

[0063]

[0064]

[0065] Combined with Figure 6 As shown, the experimental parameters of the blade design of the anti-rotation blade 8 during the experiment are as follows:

[0066] Design parameters of the anti-rotation blade 8

[0067] Coordinate parameters of the design parameters of the anti-rotation blade 8 (parallel to the air flow profile)

[0068]

[0069] The typical working conditions and requirements in the experimental stage of the present invention are as follows:

[0070]

[0071]

[0072] Rated power of the water-cooled motor 7: 45 kW, speed regulation range 360 r / min to 7200 r / min, rotational speed control accuracy of the impeller 71: 0.02% (highest speed), vibration intensity during operation of the fan section under rated conditions: ≤ 4.5 mm / s, clearance between the inner side wall of the impeller 71 and the tip inlet cylinder 4 is less than 0.4 mm (single side), looking along the axis of the fan section in the air flow direction, the impeller 71 rotates counterclockwise, the rotor, the head cover 31 and the tail cover 51 of the water-cooled motor 7 have a step difference along the air flow, and the step difference is not greater than 1.0 mm, the included angle between the axis of the fan section cavity and the axis of the rotor hub shaft of the impeller 71 and the axis of the power fan section is less than 0.5°. After multiple experiments, it is proved that the present invention can effectively replace the high-pressure gas storage tank as the power source of the wind tunnel and has high stability.

Claims

1. A subsonic calibration device power fan section, comprising a base (1), characterized in that: An inlet expansion joint (2) is mounted on the base (1), the right end of the inlet expansion joint (2) is fixedly connected to a head cover cylinder (3), a head cover (31) is fixedly mounted inside the head cover cylinder (3), and the right end of the head cover cylinder (3) is fixedly connected to an inlet cylinder (4), the right end of the inlet cylinder (4) is fixedly connected to a tail cover cylinder (5), the tail cover cylinder (5) and the inlet cylinder (4) are both fixedly mounted on the table of the base (1), a water-cooled motor (7) and a tail cover (51) are fixedly mounted inside the tail cover cylinder (5), and the output of the water-cooled motor (7) is fixedly mounted on the table of the base (1). The outlet end faces the direction of the head cover (31), and the output end of the water-cooled motor (7) is sleeved with an impeller (71), the tail cover (51) is fixedly mounted on the right surface of the water-cooled motor (7), the right end of the tail cover cylinder (5) is fixedly connected with an outlet expansion joint (6), a plurality of anti-rotation blades (8) are fixedly mounted between the inner wall of the tail cover cylinder (5) and the water-cooled motor (7), the angle between the rotor hub shaft of the impeller (71) and the axis of the power fan section is less than 0.5°, and the anti-rotation blades (8) are mounted at an angle of 77.16° to the axis of the water-cooled motor (7).

2. The power fan section of a subsonic calibration device according to claim 1, characterized in that: An encoder (72) is installed at the right end of the output shaft of the water-cooled motor (7) via a coupling.

3. The power fan section of a subsonic calibration device according to claim 2, characterized in that: Two vibration sensors (73) are fixedly mounted on the right end bearing base of the water-cooled motor (7), and the vibration sensors (73) and the encoder (72) are both located in the tail cover (51).

4. The power fan section of a subsonic calibration device according to claim 3, characterized in that: The connection cables of the vibration sensor (73) and the encoder (72) of the water-cooled motor (7) are routed inside the corresponding anti-rotation blades (8) and then penetrate the inlet cylinder (4).

5. The power fan section of a subsonic calibration device according to claim 1, characterized in that: The number of the anti-rotation blades (8) assembled is twelve, and the twelve anti-rotation blades (8) are arranged in the inlet cylinder (4) at equal intervals in the circumferential direction.

6. The power fan section of a subsonic calibration device according to claim 1, characterized in that: An inlet pressure measuring tube (41) and an outlet pressure measuring tube (42) are respectively fixedly mounted on the air inlet end and the air storage end of the inlet cylinder (4).

7. The power fan section of a subsonic calibration device according to claim 1, characterized in that: The gap between the blade tip of the impeller (71) and the inner wall of the inlet cylinder (4) is less than 0.4 mm.

8. The power fan section of a subsonic calibration device according to claim 1, characterized in that: The inlet expansion joint (2) comprises an expansion joint flange A (21), an expansion joint inner liner A (22) is fixedly mounted on the right end of the expansion joint flange A (21), an expansion joint corrugated node A (23) is fixedly mounted between the expansion joint inner liner A (22) and the head cover cylinder (3), and an expansion joint adjustment thread A (24) is installed between the expansion joint flange A (21) and the head cover cylinder (3).

9. The power fan section of a subsonic calibration device according to claim 1, characterized in that: The outlet expansion joint (6) comprises an expansion joint flange B (61), an expansion joint inner liner B (62) is fixedly installed at the left end of the expansion joint flange B (61), an expansion joint corrugated node B (63) is fixedly installed between the expansion joint inner liner B (62) and the tail cover cylinder (5), and an expansion joint adjustment thread B (64) is installed between the expansion joint flange B (61) and the tail cover cylinder (5).

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