Maritime work magnetic suspension supergravity wind tunnel test device

Abstract

The invention discloses a maritime work magnetic suspension supergravity wind tunnel test device, which relates to the field of maritime work wind tunnel test equipment, and comprises a test cavity, a first annular permanent magnet guide rail, a second annular permanent magnet guide rail, a vehicle body model test cabin, a linear motor and a test model, the simulation gravity direction required by the test model faces the first annular permanent magnet guide rail. Underground rock serves as a carrier of the first annular permanent magnet guide rail and the second annular permanent magnet guide rail, compared with an existing annular permanent magnet guide rail, the loading capacity is greatly improved, the inner diameter of a test cavity can reach 20 m or above, the system error is reduced to 1% or below, the operation rotating speed can reach 940 km / h, and the test precision is effectively improved; the gravity and wind power of the actual environment of the test model can be simulated in the test process, and the wind tunnel test requirements of the test model are met.

Description

Technical Field

[0001] The present invention relates to the field of offshore wind tunnel test equipment, in particular to an offshore magnetic levitation supergravity wind tunnel test device. Background Art

[0002] A wind tunnel test refers to an aerodynamic experimental method in which a model of an aircraft or other object is placed in a wind tunnel to study the gas flow and its interaction with the model in order to understand the aerodynamic characteristics of the actual aircraft or other objects; an offshore wind tunnel test focuses on studying the impact of offshore typhoons or hurricanes on offshore oil platforms, offshore wind power generation equipment, and large coastal buildings.

[0003] Existing wind tunnel testing equipment generally relies on the principle of relativity of motion. An aircraft or object model is fixed in a wind tunnel test chamber, and an artificial airflow is blown toward the aircraft or object model to simulate the air flow conditions during actual operation and obtain test data. The following are the main problems encountered when using current wind tunnel testing equipment for offshore wind tunnel testing:

[0004] (1) The size of offshore models is usually very large, and most existing wind tunnels cannot meet the requirements;

[0005] (2) For offshore structures, gravity and wind usually have a combined effect. Therefore, it is necessary to simulate the gravity environment at the same time when conducting wind tunnel tests. Existing wind tunnels cannot meet the requirements for simulating the gravity environment.

[0006] (3) The theoretical basis of wind tunnel experiments is the similarity principle. The similarity principle requires that all similarity criteria be met between the wind tunnel flow field and the real flow field, or that the numbers of all similarity criteria corresponding to the two flow fields are equal. Traditional wind tunnel tests are difficult to fully meet the above conditions. The most common major similarity criterion that is not met is that the Reynolds number of the subsonic wind tunnel is not enough. Take the Boeing 737 aircraft as an example. The Boeing 737 aircraft usually flies at a cruising altitude (9000m) and a cruising speed (927km / h), with a Reynolds number of 2.4×107. However, in a 3-meter subsonic wind tunnel, the test can only be carried out at a wind speed of 100m / s (360km / h), and the Reynolds number is only about 1.4×106. The two are far apart. The failure of wind tunnel tests to meet the similarity principle will inevitably lead to inaccurate test results.

[0007] (4) When an aircraft is flying or an offshore object is actually used, the atmosphere is boundless. In a traditional wind tunnel, however, the airflow is affected by the wind tunnel environment and has boundaries. The existence of boundaries limits the curvature of the air streamlines near the boundaries, making the wind tunnel flow field different from the real flow field.

[0008] To address these technical issues, some researchers have used ultra-gravity centrifuge model test equipment to conduct aerodynamic tests on offshore models. These centrifuges are typically arm or drum centrifuges. However, when using a centrifuge to simulate Earth's gravity, it's important to note that Earth's gravity is essentially perpendicular to the ground. In a centrifuge, due to the limited rotation radius, the model's gravity field always has an angle with the actual ground gravity field, inevitably leading to some systematic errors. Analysis shows that for a rotation radius of 4.5 meters, the error is approximately 5%, and for a radius of 8.5 meters, the error is approximately 2%. This systematic error is still relatively large for scientific research, so increasing the rotation radius is necessary. Due to material strength limitations, the radius and capacity of arm centrifuges have reached and are nearing safety limits, making it difficult to increase them. Similarly, test accuracy cannot be improved, and thus, the aforementioned systematic error issue remains unresolved.

[0009] Therefore, the use of existing ultra-gravity centrifugal model test equipment to conduct marine model aerodynamic tests still cannot solve the above problems. In view of this, how to provide a marine wind tunnel test equipment that can fully or partially solve the above technical problems is a technical problem that people in this field urgently need to solve. Summary of the Invention

[0010] The purpose of the present invention is to provide a marine magnetic suspension supergravity wind tunnel test device to solve the problems existing in the prior art.

[0011] To achieve the above-mentioned object, the present invention provides the following solution: The present invention provides a marine magnetic levitation supergravity wind tunnel test device, comprising:

[0012] A test cavity, wherein the test cavity is formed by a depression in the ground;

[0013] a first annular permanent magnetic guide rail, the first annular permanent magnetic guide rail being adapted to the shape of the test cavity and being fixedly arranged on the inner wall of the test cavity;

[0014] a second annular permanent magnetic guide rail, wherein the second annular permanent magnetic guide rail is fixedly arranged on the bottom surface of the test cavity, the second annular permanent magnetic guide rail is located on the inner side of the first annular permanent magnetic guide rail and is arranged adjacent to the first annular permanent magnetic guide rail;

[0015] A vehicle model test cabin, wherein the vehicle model test cabin is respectively provided with superconducting blocks corresponding to the first annular permanent magnet guide rail and the second annular permanent magnet guide rail, the vehicle model test cabin forms a magnetic levitation connection with the first annular permanent magnet guide rail and the second annular permanent magnet guide rail through the superconducting blocks, and the rotation radius of the vehicle model test cabin is greater than 20 meters;

[0016] There are two linear motors, the stator and rotor of one linear motor are fixedly arranged on the first annular permanent magnet guide rail and the vehicle model test chamber, respectively, and the stator and rotor of the other linear motor are fixedly arranged on the second annular permanent magnet guide rail and the vehicle model test chamber, respectively;

[0017] A test model is fixedly arranged on the outer surface of the vehicle body model test chamber, and the simulated gravity direction required for the test of the test model is toward the first annular permanent magnetic guide rail.

[0018] Furthermore, the vehicle body model test chamber is provided with power equipment, data acquisition equipment and wireless communication equipment. The power equipment supplies power to the data acquisition equipment and the wireless communication equipment. The wireless communication equipment is electrically connected to the data acquisition equipment and can transmit data to an external computer terminal.

[0019] Furthermore, the end of the vehicle model test chamber is streamlined.

[0020] Furthermore, the maximum rotation speed of the test model is 940 km / h.

[0021] Furthermore, it also includes:

[0022] An air intake duct, the air intake duct being fixedly mounted on the vehicle model test cabin, with an air inlet thereof facing the vehicle model test cabin in the direction of travel along the first annular permanent magnetic guide rail; the air intake duct being provided with a plurality of air outlets, the plurality of air outlets corresponding to the first annular permanent magnetic guide rail and / or the second annular permanent magnetic guide rail;

[0023] A blower is arranged in the air inlet duct, with its air outlet end facing the air outlet.

[0024] Furthermore, the test model is one of an aircraft model, a building model and a marine engineering model.

[0025] The present invention discloses the following technical effects:

[0026] 1. Using underground rock and soil as the carrier of the first and second annular permanent magnetic guide rails, the load capacity is greatly improved compared with the existing annular permanent magnetic guide rails. The inner diameter of the test cavity can reach more than 20 meters, the system error is reduced to less than 1%, and the operating speed can reach 940km / h, effectively improving the test accuracy. During the test, it can simultaneously simulate the gravity and wind force of the actual environment of the test model, meeting the requirements of the wind tunnel test of the test model.

[0027] 2. Based on the original lateral permanent magnetic guide rails, a bottom permanent magnetic guide rail is added. The bottom permanent magnetic guide rail provides auxiliary magnetic levitation support for the vehicle model test cabin. The lateral permanent magnetic guide rail provides lateral magnetic levitation support for the vehicle model test cabin. There is no need to evacuate the test cavity. The high temperature generated during operation is naturally dissipated through the test cavity connected to the outside world. The wind resistance generated during operation is minimized by the streamlined end. At the same time, it can achieve no boundaries in the atmosphere during the wind tunnel test, thereby improving the test accuracy.

[0028] 3. The present application provides an air intake duct and a blower on the vehicle model test chamber. The blower blows air toward the first annular permanent magnet guide rail and / or the second annular permanent magnet guide rail through the air outlet to form an air cushion, which can realize the function of adjusting the suspension force of the vehicle model test chamber and further improve the test accuracy.

[0029] 4. The test model is set on the outer surface of the vehicle model test chamber. In addition to being applicable to marine engineering models, it is also suitable for various test models that require the assistance of a centrifuge, such as aircraft models and building models. It is very open. And because the present application has a test cavity with an inner diameter of more than 20 meters, the volume is large, there is more air in the cavity, the flow field is very stable, and there is no rotating structure such as a cantilever or a rotating cabin to stir the air, the test accuracy can be greatly improved.

[0030] 5. Currently, large-scale centrifuge testing equipment for geotechnical and offshore engineering suffers from high single-test costs and lengthy preparation times, leading to underutilization and wasteful use of equipment. Compared to centrifuge testing, wind tunnel testing offers lower model preparation costs and shorter manufacturing times. By combining centrifuges with wind tunnel testing capabilities, the previously underutilized centrifuge capacity can be effectively utilized, allowing the investment in the equipment to achieve greater scientific impact. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0032] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0033] Figure 2 This is a schematic structural diagram of a vehicle body model test chamber and a test model of the present invention;

[0034] Figure 3 This is a schematic diagram of the vehicle model test cabin structure;

[0035] Figure 4Schematic diagram of the vehicle model test cabin equipped with an aircraft model;

[0036] Figure 5 Schematic diagram of the building model mounted on the vehicle model test cabin;

[0037] Among them, 1. First annular permanent magnet guide rail; 2. Second annular permanent magnet guide rail; 3. Vehicle model test cabin; 4. Superconducting block; 5. Test cavity; 6. Test model; 7. Air intake duct; 8. Air inlet; 9. Air outlet. DETAILED DESCRIPTION

[0038] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. 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 making creative efforts are within the scope of protection of the present invention.

[0039] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0040] like Figure 1-Figure 3 The present invention provides a marine magnetic levitation supergravity wind tunnel test device, comprising: a test cavity 5, the test cavity 5 is formed by a downward depression of the ground; a first annular permanent magnet guide rail 1, the first annular permanent magnet guide rail 1 is adapted to the shape of the test cavity 5 and is fixedly arranged on the inner side wall of the test cavity 5; a second annular permanent magnet guide rail 2, the second annular permanent magnet guide rail 2 is fixedly arranged on the bottom surface of the test cavity 5, the second annular permanent magnet guide rail 2 is located on the inner side of the first annular permanent magnet guide rail 1 and is arranged adjacent to the first annular permanent magnet guide rail 1; a vehicle model test cabin 3, the vehicle model test cabin 3 is respectively provided with superconducting blocks corresponding to the first annular permanent magnet guide rail 1 and the second annular permanent magnet guide rail 2 4. The vehicle body model test cabin 3 forms a magnetic levitation connection with the first annular permanent magnet guide rail 1 and the second annular permanent magnet guide rail 2 through the superconducting block 4, and the rotation radius of the vehicle body model test cabin 3 is greater than 20 meters; there are two linear motors, the stator and rotor of one linear motor are respectively fixed on the first annular permanent magnet guide rail 1 and the vehicle body model test cabin 3, and the stator and rotor of the other linear motor are respectively fixed on the second annular permanent magnet guide rail 2 and the vehicle body model test cabin 3; the test model 6 is fixed on the outer surface of the vehicle body model test cabin 3, and the simulated gravity direction required for the test of the test model 6 is toward the first annular permanent magnet guide rail 1.

[0041] In this embodiment, the vehicle model test chamber 3 is equipped with power equipment, data acquisition equipment, and wireless communication equipment. The power equipment provides power to the data acquisition and wireless communication equipment, which is electrically connected to the data acquisition equipment and capable of transmitting data to an external computer terminal. The ends of the vehicle model test chamber 3 are streamlined. The test model 6 has a maximum rotational speed of 940 km / h.

[0042] In this embodiment, it also includes an air intake duct 7, which is fixedly arranged on the vehicle model test cabin 3, and its air inlet 8 faces the forward direction of the vehicle model test cabin 3 along the first annular permanent magnet guide rail 1; the air intake duct 7 is provided with multiple air outlets 9, and the multiple air outlets 9 correspond to the first annular permanent magnet guide rail 1 and / or the second annular permanent magnet guide rail 2; the blower is arranged in the air intake duct 7, and its air outlet end faces the air outlet 9.

[0043] In this embodiment, the test model 6 is a marine model. Figure 3 In some other embodiments, the test model 6 can also be an aircraft model, a building model, or a similar model. Figure 4-Figure 5 shown.

[0044] Experimental Example 1

[0045] The following describes the system error. The vehicle model test chamber 3 performs uniform circular motion along the first annular permanent magnet guide rail 1 at an angular velocity of ω. Assuming the distance R between the outer side of the vehicle model test chamber 3 and the center of rotation, and the height h of the vehicle model test chamber 3, in the reference frame of the vehicle model test chamber 3:

[0046] Car body model test chamber 3 The centrifugal acceleration on the outside of car body model test chamber 3:

[0047] a o =ω 2 R

[0048] Car body model test chamber 3 The centrifugal acceleration on the inside of car body model test chamber 3:

[0049] a i =ω 2 (Rh)

[0050] Therefore, the system error caused by the difference in internal and external centrifugal acceleration is:

[0051]

[0052] For a car body model test chamber 3 with an outer side 4.5m away from the rotation center (i.e., a rotation radius of 4.5m) and a height of 20cm, the error is:

[0053]

[0054] For a car model test chamber 3 with an outer side 8.5m away from the rotation center and a height of 20cm, the error is:

[0055]

[0056] For a car model test chamber 3 with an outer side 20m away from the rotation center and a height of 20cm, the error is:

[0057]

[0058] About the error of force angle:

[0059] When the vehicle model test chamber 3 performs uniform circular motion with an angular velocity of ω along the horizontal track, the vehicle model test chamber 3 is subjected to the earth's gravitational acceleration, denoted as g=1G, and the centrifugal force in the reference frame of the vehicle model test chamber 3. The resultant force forms an angle θ with the horizontal direction.

[0060]

[0061] Car body model test chamber 3 Car body model test chamber 3 outer angle:

[0062]

[0063] Car body model test chamber 3 Car body model test chamber 3 inner angle:

[0064]

[0065] Therefore, the systematic error in angle caused by the difference in internal and external centrifugal acceleration is:

[0066]

[0067] When the centrifugal acceleration outside the vehicle model test chamber 3 is 100G,

[0068] For a car model test chamber 3 with a distance of 4.5m from the outer side to the rotation center and a height of 20cm, the error is:

[0069]

[0070] For a car model test chamber 3 with an outer side 8.5m away from the rotation center and a height of 20cm, the error is:

[0071]

[0072] For a car model test chamber 3 with an outer side 20m away from the rotation center and a height of 20cm, the error is:

[0073]

[0074] In summary, when other conditions remain unchanged, the larger the rotation radius, the smaller the system error. When the rotation radius is 20 meters, the system error is about 1%. In this embodiment, the preferred rotation radius is 22 meters. Under the condition that the vehicle model test chamber 3 is 20 cm high, the system error is approximately equal to 0.98%.

[0075] Symbol meaning table:

[0076]

[0077] Experimental Example 2

[0078] When testing using Example 1 of the present application, the maximum rotational speed can reach 940 km / h, the maximum G force (toward the first annular permanent magnet guide rail 1) can reach 100 G, and when conducting wind tunnel tests on the aircraft, the Reynolds number can reach 2.4×107.

[0079] In the description of the present invention, it should be understood that the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" and the like to indicate orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0080] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by persons skilled in the art should fall within the scope of protection defined by the claims of the present invention.

Claims

1. A marine magnetic levitation supergravity wind tunnel test device, characterized in that: include: A test cavity (5), wherein the test cavity (5) is formed by a downward depression in the ground; a first annular permanent magnetic guide rail (1), the first annular permanent magnetic guide rail (1) being adapted in shape to the test cavity (5) and being fixedly arranged on the inner side wall of the test cavity (5); a second annular permanent magnetic guide rail (2), the second annular permanent magnetic guide rail (2) being fixedly arranged on the bottom surface of the test cavity (5), the second annular permanent magnetic guide rail (2) being located on the inner side of the first annular permanent magnetic guide rail (1) and being arranged adjacent to the first annular permanent magnetic guide rail (1); A vehicle body model test cabin (3), wherein the vehicle body model test cabin (3) is provided with superconducting blocks (4) corresponding to the first annular permanent magnet guide rail (1) and the second annular permanent magnet guide rail (2), respectively; the vehicle body model test cabin (3) forms a magnetic suspension connection with the first annular permanent magnet guide rail (1) and the second annular permanent magnet guide rail (2) through the superconducting blocks (4); and the rotation radius of the vehicle body model test cabin (3) is greater than 20 meters; There are two linear motors, the stator and rotor of one linear motor being fixedly arranged on the first annular permanent magnet guide rail (1) and the vehicle model test chamber (3), respectively, and the stator and rotor of the other linear motor being fixedly arranged on the second annular permanent magnet guide rail (2) and the vehicle model test chamber (3), respectively; A test model (6) is fixedly arranged on the outer surface of the vehicle body model test chamber (3), and the simulated gravity direction required for the test of the test model (6) is toward the first annular permanent magnetic guide rail (1).

2. The marine magnetic levitation supergravity wind tunnel test device according to claim 1, characterized in that: The vehicle body model test chamber (3) is provided with power equipment, data acquisition equipment and wireless communication equipment. The power equipment supplies power to the data acquisition equipment and the wireless communication equipment. The wireless communication equipment is electrically connected to the data acquisition equipment and can transmit data to an external computer terminal.

3. The marine magnetic levitation supergravity wind tunnel test device according to claim 1, characterized in that: It is characterized by: The end of the vehicle model test chamber (3) is streamlined.

4. The marine magnetic levitation supergravity wind tunnel test device according to claim 1, characterized in that: The maximum rotation speed of the test model (6) is 940 km / h.

5. The marine magnetic levitation supergravity wind tunnel test device according to claim 1, characterized in that: Also includes: An air intake duct (7), the air intake duct (7) being fixedly arranged on the vehicle model test chamber (3), with its air inlet (8) facing the vehicle model test chamber (3) in the forward direction of the first annular permanent magnetic guide rail (1); the air intake duct (7) being provided with a plurality of air outlets (9), the plurality of air outlets (9) corresponding to the first annular permanent magnetic guide rail (1) and / or the second annular permanent magnetic guide rail (2); A blower is provided in the air inlet duct (7), with its air outlet end facing the air outlet (9).

6. The marine magnetic levitation supergravity wind tunnel test device according to claim 1, characterized in that: The test model (6) is one of an aircraft model, a building model and a marine engineering model.

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