A vacuum system suitable for an arc tunnel

Abstract

The present application relates to the technical field of aerodynamic thermal ground simulation equipment, and particularly relates to a vacuum system suitable for an arc wind tunnel. The vacuum system comprises a wind tunnel pipeline, a vacuum storage unit, a cooling unit and a vacuum pumping unit. The upstream of the wind tunnel pipeline is connected with the arc wind tunnel, and the downstream of the wind tunnel pipeline is provided with a first branch pipeline and a second branch pipeline. The first branch pipeline is connected with the vacuum storage unit, and the second branch pipeline is connected with the cooling unit. The vacuum storage unit comprises a plurality of vacuum storage tanks and their matched storage tank pipelines, and the storage tank pipelines are connected with the first branch pipeline. The vacuum pumping unit comprises a plurality of vacuum units and their matched unit pipelines, and the unit pipelines are connected with the cooling unit. The technical scheme provided by the present application expands the storage volume of the vacuum system of the arc wind tunnel, improves the vacuum pumping speed, and provides a large-volume and high-speed vacuum environment for the arc wind tunnel test.

Description

Technical Field

[0001] This invention relates to the field of aerodynamic thermal ground simulation equipment, and in particular to a vacuum system suitable for electric arc wind tunnels. Background Technology

[0002] With the rapid development of aerothermal ground simulation technology, various types of electric arc wind tunnels are widely used in related experimental research. The vacuum system is a core component of the electric arc wind tunnel, and its performance directly determines the stability of the electric arc wind tunnel test environment and the accuracy of the test results, playing an irreplaceable key role in the operation of the electric arc wind tunnel. Currently, the frequency and scale of electric arc wind tunnel tests are gradually increasing. These intensive tests generate a large amount of exhaust gas, placing extremely high demands on the pumping capacity of the vacuum system. Simultaneously, electric arc wind tunnel tests require the vacuum system to maintain a very low pressure environment for extended periods to simulate the aerodynamic and thermal environment of an aircraft flying at high altitudes, ensuring the realism and reliability of the test conditions. Existing vacuum systems struggle to simultaneously meet the dual requirements of high pumping speed and large capacity. Therefore, developing a vacuum system capable of high pumping speed and large-capacity pumping and exhaust, and able to maintain a low-pressure environment for a long time to meet the needs of intensive arc wind tunnel testing, has become an urgent technical challenge in the field of aerodynamic ground simulation technology. Summary of the Invention

[0003] The purpose of this invention is to provide a vacuum system suitable for electric arc wind tunnels. This vacuum system can solve the technical problems of insufficient pumping speed and limited volume of existing vacuum systems, which make it impossible to quickly pump out the large amount of exhaust gas generated by intensive electric arc wind tunnel tests and difficult to maintain a low-pressure environment for a long time. This helps to improve the stability of the test environment and the accuracy of test results.

[0004] This invention provides a vacuum system suitable for electric arc wind tunnels, including wind tunnel piping, a vacuum storage unit, a cooling unit, and a vacuum suction unit; The upstream of the wind tunnel pipe is connected to the electric arc wind tunnel, and the downstream of the wind tunnel pipe is provided with a first branch pipe and a second branch pipe. The first branch pipe is connected to the vacuum storage unit, and the second branch pipe is connected to the cooling unit. The vacuum storage unit includes multiple vacuum storage tanks and their associated storage tank pipelines, and the storage tank pipelines are connected to the first branch pipeline; The vacuum suction unit includes multiple vacuum units and their associated unit pipelines, which are connected to the cooling unit. The cooling unit includes a cryogenic compressor, the upstream of which is connected to the second branch pipeline, and the downstream of which is connected to the unit pipeline.

[0005] Furthermore, it also includes a denitrification system, which is connected to the vacuum suction unit via an exhaust gas pipeline.

[0006] Furthermore, one of the vacuum storage tanks in the vacuum storage unit and its associated storage tank pipelines are combined to form a storage unit, and multiple storage units are connected in parallel.

[0007] Furthermore, one of the vacuum units in the vacuum suction unit and its associated unit pipelines are combined to form a suction unit, and multiple suction units are connected in parallel.

[0008] Furthermore, the cryogenic machine reduces the temperature of the exhaust gas from the electric arc wind tunnel to -5°C to 5°C.

[0009] Furthermore, a pressure detection component is provided at the inlet of the vacuum unit for measuring the airflow pressure.

[0010] Furthermore, the airflow pressure is divided into three zones: a safe zone, a warning zone, and a danger zone. The vacuum unit has an automatic frequency conversion operation function. When the airflow pressure is in the warning zone, the vacuum unit automatically switches to low frequency operation mode.

[0011] Furthermore, the vacuum unit has an automatic start-stop function. When the gas flow pressure is in a dangerous area, the vacuum unit automatically stops operating, and when the gas flow pressure is in a safe area, the vacuum unit automatically resumes operation.

[0012] Furthermore, the wind tunnel pipeline, the storage tank pipeline, and the unit pipeline are all equipped with bidirectional sealing vacuum valves, which have both short-range on-site control and long-range control functions.

[0013] Furthermore, the connections of the wind tunnel pipeline, the vacuum storage tank, the storage tank pipeline, the cryogenic compressor, the vacuum unit, and the unit pipeline are all sealed connections, and the parts that come into contact with the wind tunnel exhaust gas are all treated with anti-corrosion measures.

[0014] In summary, compared with the prior art, the present invention has the following advantages: The vacuum suction unit provided by this invention includes multiple vacuum storage tanks and their supporting storage tank pipelines, which expands the storage volume of the vacuum system. The vacuum suction unit also includes multiple vacuum units and their supporting unit pipelines, which improves the vacuum pumping speed. It is suitable for the temporary storage and rapid extraction of a large amount of exhaust gas generated by intensive arc wind tunnel tests, avoiding exhaust gas accumulation. Furthermore, it can be flexibly adjusted according to the frequency of arc wind tunnel tests and the exhaust gas emission volume to meet the test requirements of different scales.

[0015] In the technical solution provided by this invention, a first branch pipe and a second branch pipe are set downstream of the wind tunnel pipeline, which are respectively connected to the vacuum storage unit and the cooling unit to realize the diversion treatment of exhaust gas: part of the exhaust gas enters the vacuum storage tank for temporary storage, ensuring the capacity requirement for temporary storage of exhaust gas; the other part of the exhaust gas is cooled by the cooling unit and then pumped out by the vacuum unit, which further improves the vacuum pumping speed and ensures the safe operation of the vacuum unit.

[0016] The vacuum system provided by this invention can be applied to the research field of aerodynamic thermal ground simulation technology, providing a large-volume, high-pumping-speed vacuum environment for electric arc wind tunnel tests. Attached Figure Description

[0017] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the system structure in an embodiment of the present invention.

[0019] Explanation of reference numerals in the attached drawings: 1-Arc wind tunnel; 2-Wind tunnel piping; 201-First branch piping; 202-Second branch piping; 3-Vacuum storage tank; 4-Storage tank piping; 5-Cryogenic compressor; 6-Vacuum unit; 7-Unit piping; 8-Denitrification system; 9-Exhaust gas piping; 10-Vacuum valve. Detailed Implementation

[0020] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0022] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified. Furthermore, the terms "installed," "connected," and "linked" should be interpreted broadly; for example, they may refer to a fixed connection, a detachable connection, or an integral connection; they may refer to a mechanical connection or an electrical connection; they may refer to a direct connection or an indirect connection through an intermediate medium; and they may refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0023] Example A vacuum system suitable for electric arc wind tunnels, such as Figure 1 As shown, it includes wind tunnel piping 2, vacuum storage unit, cooling unit, and vacuum suction unit, the details of which are as follows: The upstream of the wind tunnel pipe 2 is connected to the outlet of the electric arc wind tunnel 1. The downstream of the wind tunnel pipe 2 is provided with a first branch pipe 201 and a second branch pipe 202. The first branch pipe 201 is connected to the vacuum storage unit, and the second branch pipe 202 is connected to the cooling unit to realize the diversion and transportation of airflow.

[0024] The vacuum storage unit includes multiple vacuum storage tanks 3 and their associated storage tank pipelines 4. Each storage tank pipeline 4 is connected to a corresponding first branch pipeline 201. Each vacuum storage tank 3 and its associated storage tank pipeline 4 form a storage unit. Multiple storage units are used in parallel to expand the storage volume of the vacuum system, according to the requirements of the arc wind tunnel test. In this embodiment, the vacuum storage tanks 3 are vacuum spherical tanks, with six vacuum spherical tanks, totaling six storage units. Each storage unit has a volume of 6000 m³. 3 The maximum volume when operating in parallel is 36,000 m³. 3 .

[0025] The cooling unit employs a cryogenic compressor 5, which is connected upstream to the second branch pipe 202 and downstream to the unit pipe 7. The cryogenic compressor 5 can cool the high-temperature exhaust gas from the arc wind tunnel to -5°C to 5°C, ensuring the safe operation of the vacuum unit and further improving the vacuum pumping speed. In this embodiment, the cryogenic compressor 5 can reduce the exhaust gas temperature of the arc wind tunnel to -3°C, which is relatively economical.

[0026] The vacuum pumping unit includes multiple vacuum units 6 and their associated piping 7, which are connected to a cooling unit. Each vacuum unit 6 and its associated piping 7 form a pumping unit. Multiple pumping units are used in parallel to increase the vacuum pumping speed, according to the requirements of the arc wind tunnel test. In this embodiment, ten pumping units are provided, each with a pumping rate of 10,000 L / s, and the maximum pumping rate when operating in parallel is 100,000 L / s.

[0027] A pressure detection component is installed at the inlet of vacuum unit 6 to measure the airflow pressure. The airflow pressure is divided into three zones: a safe zone, a warning zone, and a danger zone. The airflow pressure in the safe zone is ≤2500Pa, the airflow pressure in the warning zone is between 2500Pa and 3500Pa, and the airflow pressure in the danger zone is ≥3500Pa.

[0028] Vacuum unit 6 is equipped with a controller, which has automatic frequency conversion operation and automatic start-stop functions: when the pressure detection component detects that the airflow pressure is in the warning area, the controller issues a command and vacuum unit 6 automatically switches to low frequency operation mode; when the airflow pressure is detected to be in the danger area, the controller issues a command and vacuum unit 6 automatically stops operation to prevent equipment damage; when the airflow pressure is detected to return to the safe area, the controller issues a command and vacuum unit 6 automatically resumes operation to ensure the stability of the system vacuum.

[0029] From a construction cost perspective, increasing the vacuum pumping speed is more important than expanding the storage volume; from an operation and maintenance cost perspective, expanding the storage volume is more important than increasing the vacuum pumping speed. In this embodiment, the cost ratio of constructing a storage unit to constructing a suction unit is approximately 10:1.

[0030] In this embodiment, the wind tunnel pipeline 2, storage tank pipeline 4, and unit pipeline 7 are all equipped with bidirectional sealing vacuum valves 10. The vacuum valves 10 have both short-range on-site control and long-range control functions. Maintenance personnel can flexibly adjust the system's operating status by controlling the vacuum valves on-site or remotely.

[0031] All connections of the wind tunnel pipeline 2, vacuum storage tank 3, storage tank pipeline 4, cryogenic machine 5, vacuum unit 6, and unit pipeline 7 are sealed connections, and all parts in contact with the wind tunnel exhaust gas are treated with anti-corrosion measures.

[0032] It also includes a denitrification system 8, which uses conventional denitrification devices in the field. It is connected to the outlet of the vacuum unit 6 through the exhaust gas pipeline 9 to denitrify the exhaust gas emitted by the vacuum unit 6 to meet environmental emission requirements.

[0033] The operation process of the vacuum system provided by this invention is as follows: Before vacuum unit 6 is put into operation, wind tunnel pipeline 2 and unit pipeline 7 are both closed, while storage tank pipeline 4 is open. When the vacuum system is in operation, vacuum unit 6 is started first. When the pressure difference between the gas in vacuum unit 6 and the gas in vacuum storage tank 3 meets the opening conditions of unit pipeline 7, unit pipeline 7 is opened to evacuate vacuum storage tank 3. When the gas pressure in vacuum storage tank 3 meets the pressure required for the operation of arc wind tunnel 1, wind tunnel pipeline 2 is opened to establish vacuum conditions for arc wind tunnel 1.

[0034] When the electric arc wind tunnel is running, the exhaust gas generated is divided into two parts after passing through the wind tunnel pipeline 2. One part enters the vacuum storage tank 3 through the first branch pipeline 201 and the storage tank pipeline 4, and the other part enters the cryogenic unit 5 through the second branch pipeline 202. After being cooled, it enters the vacuum unit 6 through the unit pipeline 7, and after compression, it is discharged into the denitrification system 8.

[0035] The exhaust gas in vacuum tank 3 enters cryogenic compressor 5 under the influence of pressure difference, repeating the above process, ultimately providing a usable vacuum environment for arc wind tunnel 1. Parallel operation of multiple vacuum tanks 3 can expand the vacuum volume, and parallel operation of multiple vacuum units 6 can increase the vacuum pumping speed. Cryogenic compressor 5 lowers the exhaust gas temperature to a suitable level, ensuring the safe operation of vacuum units 6 and further improving the vacuum pumping speed.

[0036] The combined use of the above-mentioned devices in this invention can pump out the acidic exhaust gas generated by the arc wind tunnel. By expanding the storage volume of the vacuum system, increasing the vacuum pumping speed by connecting units in parallel, and ensuring safe operation by cryogenic exhaust gas, a high-speed, high-capacity vacuum system is provided to ensure the stable operation of the arc wind tunnel for a long time with a large flow rate.

[0037] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A vacuum system suitable for electric arc wind tunnels, characterized in that, Includes wind tunnel piping (2), vacuum storage unit, cooling unit, and vacuum suction unit; The wind tunnel pipe (2) is connected upstream to the electric arc wind tunnel, and the wind tunnel pipe (2) is provided with a first branch pipe (201) and a second branch pipe (202) downstream. The first branch pipe (201) is connected to the vacuum storage unit, and the second branch pipe (202) is connected to the cooling unit. The vacuum storage unit includes multiple vacuum storage tanks (3) and their supporting storage tank pipelines (4), and the storage tank pipelines (4) are connected to the first branch pipeline (201); The vacuum suction unit includes multiple vacuum units (6) and their supporting unit pipelines (7), and the unit pipelines (7) are connected to the cooling unit; The cooling unit includes a cryogenic compressor (5), the upstream of which is connected to the second branch pipeline (202), and the downstream of which is connected to the unit pipeline (7).

2. The vacuum system according to claim 1, characterized in that, It also includes a denitrification system (8), which is connected to the vacuum suction unit via an exhaust gas pipeline (9).

3. The vacuum system according to claim 1, characterized in that, The vacuum storage unit consists of one vacuum tank (3) and its associated storage tank pipeline (4) to form a storage unit, and multiple storage units are connected in parallel.

4. The vacuum system according to claim 1, characterized in that, One of the vacuum units (6) and its associated unit pipelines (7) in the vacuum suction unit are combined to form a suction unit, and multiple suction units are connected in parallel.

5. The vacuum system according to claim 1, characterized in that, The cryogenic machine (5) reduces the temperature of the exhaust gas from the electric arc wind tunnel to -5℃ ~ 5℃.

6. The vacuum system according to claim 1, characterized in that, The vacuum unit (6) is equipped with a pressure detection component at the inlet for measuring the airflow pressure.

7. The vacuum system according to claim 6, characterized in that, The airflow pressure is divided into three zones: a safe zone, a warning zone, and a danger zone. The vacuum unit (6) has an automatic frequency conversion operation function. When the airflow pressure is in the warning area, the vacuum unit (6) automatically switches to low frequency operation mode.

8. The vacuum system according to claim 7, characterized in that, The vacuum unit (6) has an automatic start-stop function. When the airflow pressure is in the danger zone, the vacuum unit (6) will automatically stop running, and when the airflow pressure is in the safe zone, the vacuum unit (6) will automatically resume running.

9. The vacuum system according to claim 1, characterized in that, The wind tunnel pipeline (2), the storage tank pipeline (4), and the unit pipeline (7) are all equipped with bidirectional sealing vacuum valves (10), which have both near-field control and long-distance control functions.

10. The vacuum system according to claim 1, characterized in that, The connections of the wind tunnel pipeline (2), the vacuum storage tank (3), the storage tank pipeline (4), the cryogenic machine (5), the vacuum unit (6), and the unit pipeline (7) are all sealed connections, and the parts that come into contact with the exhaust gas from the wind tunnel are all treated with anti-corrosion measures.

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