An electronic scanning valve protection device

Abstract

The present invention discloses an electronic scanning valve protection device, comprising a protection box, on which a rectangular installation groove for accommodating the electronic scanning valve is provided; a protection cover arranged on the installation groove to encapsulate the electronic scanning valve; a measuring rake arranged at the front end of the protection box for measuring the airflow parameters at the tail nozzle outlet of an aircraft; the front end of the protection box matched with the measuring rake is configured to be in a wedge shape, and the wedge angle is less than or equal to 30°. The present invention provides an electronic scanning valve protection device, which can protect the electronic scanning valve when applied to the airflow parameter measurement at the tail nozzle outlet of an air-breathing aircraft, and effectively protect the electronic scanning valve from being eroded by the high-temperature incoming flow in the measurement environment through the isolation mode of the protection box, thereby ensuring that the measurement accuracy is not affected by the environment; shortening the length of the pressure measurement pipeline and the pressure measurement response time, and improving the test efficiency and measurement accuracy.

Description

Technical Field

[0001] The present invention relates to the technical field of wind tunnel testing, and more specifically, to a device for protecting an electronic scanning valve used in measuring airflow parameters at the outlet of a tail nozzle of an air-breathing aircraft in a wind tunnel test. Background Art

[0002] Hypersonic air-breathing vehicles have become one of the hot areas of hypersonic research in various countries around the world. Accurately obtaining the engine internal flow resistance (hereinafter referred to as "internal resistance") is one of the issues that need to be focused on during the research and design of the aerodynamic layout of air-breathing vehicles. At present, there are two main technical approaches: one is direct measurement [Xu Xiaobin et al., Research on Direct Measurement Technology of Internal Flow Resistance of Ventilation Model [J], Propulsion Technology, 2013, 34(3)]; the other is indirect measurement, that is, measuring the pitot pressure and static pressure at the internal flow outlet and obtaining the internal resistance through calculation. Among them, the pitot pressure is measured by a pitot pressure probe; the static pressure measurement methods are divided into two types: (1) indirect measurement method, using DPIV technology to measure the tail nozzle outlet airflow velocity, and then converting it to obtain the outlet static pressure [Huang Zhan et al., Research on DPIV internal flow resistance measurement technology of hypersonic aircraft [J], Propulsion Technology, 2014, 34(4)]; (2) direct measurement method, using a static pressure probe to directly measure the outlet static pressure [Shu Haifeng et al., Research on experimental technology for measuring airflow parameters at the outlet of a hypersonic ventilation model nozzle [J], 2017, 31(6)].

[0003] When conducting a model surface pressure measurement test, a pressure measuring hole is usually opened on the model, and the pressure measuring hole is connected to a Teflon hose or stainless steel pipe with a diameter of 1 to 2 mm, and the other end of the pipe is connected to an electronic scanning valve. If there are not too many measuring points or the internal space of the model is large enough, the electronic scanning valve can be placed directly in the inner cavity of the model.

[0004] When measuring the airflow parameters at the tail nozzle outlet of an air-breathing aircraft, the measured point is not on the model wall but in the space enclosed by the tail nozzle wall. Therefore, the electronic scanning valve cannot be placed in the inner cavity of the model, but must be placed somewhere behind the model and take protective measures. On the other hand, under normal circumstances, the static pressure value at the nozzle outlet is very small. If the electronic scanning valve is too far away from the nozzle outlet, the response time is long and the pressure loss is large.

[0005] Therefore, it is necessary to design a scanning valve protection device to meet the needs of nozzle outlet airflow parameter measurement, which is of great significance for conducting such experiments in hypersonic wind tunnels in the future. At present, there is no relevant literature report at home and abroad. Summary of the invention

[0006] An object of the present invention is to solve at least the above problems and / or disadvantages and to provide at least the advantages which will be described hereinafter.

[0007] In order to achieve these purposes and other advantages according to the present invention, an electronic scanning valve protection device is provided, comprising:

[0008] A protection box, on which a rectangular mounting groove for accommodating the electronic scanning valve is provided;

[0009] A protective cover disposed on the mounting groove to encapsulate the electronic scanning valve;

[0010] A measuring rake arranged at the front end of the protection box for measuring airflow parameters at the tail nozzle outlet of the aircraft;

[0011] The front end of the protection box that cooperates with the measuring rake is configured to be wedge-shaped, and the wedge angle is less than or equal to 30°.

[0012] Preferably, a heat-insulating sleeve is provided on the inner side wall of the rectangular installation groove to be clearance-matched with the electronic scanning valve;

[0013] Wherein, the thermal insulation sleeve is configured to be made of polytetrafluoroethylene.

[0014] Preferably, the protection box is provided with equal straight sections at the position connected to the front end;

[0015] The rear end of the straight section is provided with an expansion section which is gradually tilted upwards to match the straight section;

[0016] A cylindrical section and a conical section are arranged behind the expansion section to lead out the lead wire of the electronic scanning valve;

[0017] Wherein, the rectangular mounting groove is arranged on the straight section and the expansion section;

[0018] The conical section is configured with a taper of 1:10 and is connected to the tail strut in the wind tunnel;

[0019] The center of the cylindrical section is about 20 mm higher than the electronic scanning valve in the longitudinal symmetry plane, and the center of the cylindrical section and the conical section opens a diameter A circular hole is provided to introduce the signal line of the electronic scanning valve into the tail support rod and then connect it to the data acquisition system.

[0020] Preferably, a fixing groove is provided at the front end of the protection box, and a positioning block matching the fixing groove structure is provided at the bottom of the measuring rake;

[0021] Among them, a triangular groove is arranged at the bottom of the protection box at a position matching the fixing groove, and the measuring block is connected and fixed to the fixing groove through a first fixing screw hole and a first fixing screw arranged on the triangular groove.

[0022] Preferably, the protective cover is configured to include two pressing plates symmetrical along the longitudinal axis of the rectangular mounting slot;

[0023] Each pressing plate has a straight section and an upward section that match the external structure of the protection box in space;

[0024] The upper surface of the straight section of each pressing plate is provided with a first arc groove, and the first arc grooves on two pressing plates are closed to form a lead-in circular hole for introducing a pressure measuring tube in a measuring rake;

[0025] The upward section of each cover plate is provided with a downwardly extending buckle plate on the side wall that cooperates with the rectangular mounting groove. The buckle plate is provided with a second arc-shaped groove at a position that cooperates with the signal line of the electronic scanning valve. The second arc-shaped grooves on the two buckle plates form an "n"-shaped wiring groove that can lead out the signal line of the electronic scanning valve when closed.

[0026] Preferably, second fixing screw holes are provided on the matching sides of the protection cover and the protection box, so as to connect and fix the protection cover and the protection box through matching second fixing screws.

[0027] Preferably, long-staple cotton is provided inside the protection box and in the holes and grooves on the protection cover to fill the gaps;

[0028] The combination of the protection box and the protection cover is integrally wrapped and sealed by adhesive tape.

[0029] A method for applying the electronic scanning valve protection device comprises:

[0030] The positioning block on the measuring rake is embedded into the triangular groove of the protection box, and the two are fixedly connected by the first screw;

[0031] Connect the pressure measuring tube of the measuring rake to the electronic scanning valve;

[0032] Embed the electronic scanning valve into the rectangular installation groove, and pass the lead wire of the electronic scanning valve through the central circular holes of the cylindrical section and the conical section;

[0033] The protective cover is placed on the rectangular installation groove so that the pressure measuring tube of the measuring rake and the signal line of the electronic scanning valve pass through the lead round hole and the wiring groove on the protective cover respectively and are fixed;

[0034] After filling the gaps inside the protection box and the holes on the protection cover with long-staple cotton, the combination of the protection box and the protection cover is wrapped and sealed as a whole with adhesive tape;

[0035] The signal line of the electronic scanning valve passing through the central circular holes of the cylindrical section and the conical section is introduced into the tail support rod and connected with the data acquisition system, and the assembly is fixed to the tail support rod.

[0036] The present invention includes at least the following beneficial effects: the present invention provides an electronic scanning valve protection device, which, when applied to the measurement of airflow parameters at the outlet of the tail nozzle of an air-breathing aircraft, can protect the electronic scanning valve connected to the measuring rake, so as to effectively protect the electronic scanning valve from being eroded by the high-temperature flow in the measurement environment through the isolation mode of the protection box, thereby ensuring that the accuracy of its measurement is not affected by the environment, and can be adapted to measure the airflow parameters at any position in the wind tunnel test, and has a wider adaptability; further, through the limitations of the various structures in the protection device, the length of the pressure measuring pipeline connecting the measuring rake and the electronic scanning valve can be greatly shortened, thereby effectively shortening the measurement response time of the electronic scanning valve and the response time of connecting to the back-end data acquisition for data collection, thereby improving the test efficiency and measurement accuracy.

[0037] Other advantages, objectives and features of the present invention will be embodied in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a schematic diagram of the top view of the structure of the electronic scanning valve protection device in one embodiment of the present invention;

[0039] Figure 2 It is a schematic diagram of the structure of the protective box and the protective cover of the present invention;

[0040] Figure 3 for Figure 1 A schematic diagram of the structure from another perspective in the figure;

[0041] Figure 4 It is a schematic diagram of the structure of the protection box of the present invention;

[0042] Figure 5 is a schematic structural diagram of one of the pressing plates in the protective cover of the present invention;

[0043] Figure 6 It is a schematic diagram of the structure of the protective cover of the present invention;

[0044] Figure 7 It is a schematic diagram of the bottom structure of the measuring rake of the present invention. DETAILED DESCRIPTION

[0045] The present invention is further described in detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0046] It should be understood that terms such as “having”, “including” and “comprising” used herein do not specify the existence or addition of one or more other elements or combinations thereof.

[0047] It should be noted that in the description of the present invention, the orientation or positional relationship indicated by the term is based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0048] In the description of the present invention, it should be noted that, unless otherwise clearly stipulated and limited, the terms "installed", "provided with", "mounted / connected", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection. It can be a mechanical connection or an electrical connection. It can be a direct connection or an indirect connection through an intermediate medium. It can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0049] Figure 1-4 , shows an implementation form of an electronic scanning valve protection device according to the present invention, which includes:

[0050] A protection box 1 is provided with a rectangular mounting groove 2 (also referred to as a rectangular groove) for accommodating an electronic scanning valve (not shown);

[0051] A protective cover 3 is arranged on the mounting groove to encapsulate the electronic scanning valve;

[0052] A measuring rake 4 arranged at the front end of the protection box for measuring airflow parameters at the tail nozzle outlet of the aircraft;

[0053] The front end 5 of the protection box that matches the measuring rake is configured to be wedge-shaped, and the wedge angle is less than or equal to 30°. In actual operation, the device consists of a protection box, a protection cover and a heat insulation sleeve. The front end of the protection box is wedge-shaped, and its wedge angle is 30°. Its function is to reduce its influence on the measurement accuracy in the test through the design of the wedge angle, and at the same time, it supports and limits the measuring rake so that it matches its measurement position. In actual application, the length of the front end is about 112mm; a rectangular groove is opened at the rear end of the protection box for placing the electronic scanning valve, so that the electronic scanning valve will not be exposed to the measurement environment, and its measurement accuracy is guaranteed not to be affected by the external environment. Through the limitation of this structure, the measurement position is not limited to the side wall inside the wind tunnel, and its position can be limited as needed. The measurement rake and the electronic scanning valve are designed as an integrated combination, which can effectively reduce the length of the pressure measuring pipeline and ensure that the response time of the electronic scanning valve is greatly shortened.

[0054] like Figure 4In another example, a heat-insulating sleeve 6 is provided on the inner wall of the rectangular installation groove, which is gap-matched with the electronic scanning valve. In this structure, the heat-insulating sleeve is installed in the rectangular groove by a small gap fit or bonding method, so that the working environment of the electronic scanning valve can be better controlled;

[0055] Among them, the thermal insulation sleeve is configured to be made of polytetrafluoroethylene. The thermal insulation sleeve material is polytetrafluoroethylene, mainly utilizing its electrical insulation, good anti-aging endurance and excellent high temperature resistance, thereby ensuring that the electronic scanning valve is not affected by the external environment in the experimental working environment, and has good stability and measurement effect.

[0056] like Figure 2 In another example, the protection box is provided with an equal straight section 7 at a position connected to the front end;

[0057] The rear end of the straight section is provided with an expansion section 8 with a shape gradually tilted upwards, and the straight section with a rectangular cross-section is provided after the wedge of the protection box, and the expansion section with a shape gradually tilted upwards is provided after the straight section, and the rectangular groove is provided on the straight section and the expansion section;

[0058] A cylindrical section 9 and a conical section 10 are arranged behind the expansion section to lead out the lead wires of the electronic scanning valve;

[0059] Wherein, the rectangular mounting groove is arranged on the straight section and the expansion section;

[0060] The conical section is configured with a taper of 1:10 and is connected to the tail strut in the wind tunnel;

[0061] The center of the cylindrical section is about 20 mm higher than the electronic scanning valve in the longitudinal symmetry plane, and the center of the cylindrical section and the conical section opens a diameter The circular hole 11 is used to lead the signal line of the electronic scanning valve into the tail support rod, and then connect it to the data acquisition system. In this structure, there is a cylindrical section after the expansion section. The center of the cylindrical section is about 20mm higher than the electronic scanning valve in the longitudinal symmetry plane. Its function is to make the circular hole for the lead-in later correspond to the outlet position of the electronic scanning valve signal line in space, reduce the bending degree of the signal line, and ensure its good service life. After the cylindrical section is a conical section with a taper of 1:10, which is connected to the existing tail support rod of the wind tunnel. In order to facilitate the selection of a matching tail support rod, all dimensions of the conical section are consistent with the dimensions of the commonly used balance interface of the wind tunnel. A circular hole with a diameter of 1:10 is opened in the center of the cylindrical section and the conical section. Lead the scanning valve signal line into the tail support rod and connect it to the data acquisition system at the rear side of the tail support rod.

[0062] like Figure 4 , 7In another example, a fixing groove 12 (also called a wedge groove) is provided at the front end of the protection box, and a positioning block 13 (also called a wedge block) matching the fixing groove structure is provided at the bottom of the measuring rake;

[0063] Among them, a triangular groove 14 is provided at the bottom of the protection box at a position matching the fixing groove, and the measuring block and the fixing groove are connected and fixed by a first fixing screw hole 15 and a first fixing screw (not shown) provided on the triangular groove. In this structure, the front end of the protection box is positioned by a 30° wedge groove and a 30° wedge block at the bottom of the pressure measuring rake, and then the screws are installed and connected to the protection box through two M5 threaded holes at the bottom of the 30° wedge block of the pressure measuring rake. The M5 screws can be installed and tightened through the triangular groove at the bottom of the protection box. In this way, the protection box and the pressure measuring rake can be conveniently installed, and the weight of the protection box can be reduced, and the load borne by the tail support rod can be reduced, which is beneficial to the safety of the test. At the same time, through the design of this structure, the length of the pressure measuring pipeline can be greatly shortened.

[0064] like Figure 5-6 , in another example, the protective cover is configured to include two pressing plates 16 symmetrical along the longitudinal axis of the rectangular mounting slot;

[0065] Each pressing plate has a straight section 17 and an upward section 18 that match the external structure of the protection box in space;

[0066] The upper surface of the straight section of each pressing plate is provided with a first arc groove 19, and the first arc grooves on the two pressing plates, when closed, form a lead-in circular hole 20 for introducing the pressure measuring tube in the measuring rake;

[0067] The upward section of each cover plate is provided with a downwardly extending pressing plate 21 on the side wall matching with the rectangular installation groove, and the pressing plate is provided with a second arc groove 22 at a position matching with the signal line of the electronic scanning valve. The second arc grooves on the two pressing plates form an "n"-shaped wiring groove 23 for leading out the signal line of the electronic scanning valve after closing. The protective cover is processed into a shape with one end raised and one end straight, and a diameter of 2 is opened in the middle of the straight section of the protective cover. The protective cover is divided into two parts along the longitudinal symmetric plane of the protective cover, which is convenient for introducing the pressure measuring tube into the protective box. An "n"-shaped wiring groove is opened at the rear edge of the raised part of the protective cover. The width of the groove and the diameter of the semicircle are 12mm. This structural design can shorten the measurement response time and improve the test efficiency.

[0068] like Figure 2In another example, a second fixing screw hole 24 is provided on the matching sides of the protective cover and the protective box, so that the protective cover and the protective box can be connected and fixed by matching second fixing screws. In this scheme, threaded holes are drilled on the sides of the protective cover and the protective box, and the two are connected and fixed with M2.5 screws to ensure their structural stability in a high flow rate environment.

[0069] In another example, long-staple cotton is provided inside the protection box and in the holes and grooves on the protection cover to fill the gaps;

[0070] The combination of the protection box and the protection cover is wrapped and sealed as a whole by tape. In this structure, after the electronic scanning valve is installed in the protection box and the protection cover is covered, the internal space of the protection box and the circular hole gap on the protection cover are filled with long-staple cotton, and then the protection box and the protection cover combination are wrapped and sealed as a whole with high-temperature tape.

[0071] A method of the electronic scanning valve protection device, comprising:

[0072] The positioning block on the measuring rake is embedded into the triangular groove of the protection box, and the two are fixedly connected by the first screw;

[0073] Connect the pressure measuring tube of the measuring rake to the electronic scanning valve;

[0074] Embed the electronic scanning valve into the rectangular installation groove, and pass the lead wire of the electronic scanning valve through the central circular holes of the cylindrical section and the conical section;

[0075] The protective cover is placed on the rectangular installation groove so that the pressure measuring tube of the measuring rake and the signal line of the electronic scanning valve pass through the lead round hole and the wiring groove on the protective cover respectively and are fixed;

[0076] After filling the gaps inside the protection box and the holes on the protection cover with long-staple cotton, the combination of the protection box and the protection cover is wrapped and sealed as a whole with adhesive tape;

[0077] The signal line of the electronic scanning valve passing through the central circular hole of the cylindrical section and the conical section is introduced into the tail support rod and connected to the data acquisition system, and the assembly is fixed to the tail support rod. In this scheme, the obtained protection device can protect the electronic scanning valve connected to the measuring rake when applied to the airflow parameter measurement of the tail nozzle outlet of the air-breathing aircraft, and can effectively protect the electronic scanning valve from being eroded by the high-temperature flow in the measurement environment through the isolation mode of the protection box, so as to ensure that the measurement accuracy is not affected by the environment.

[0078] Furthermore, by limiting the structures in the protection device, the length of the pressure measuring pipeline connecting the measuring rake and the electronic scanning valve can be greatly shortened, thereby effectively shortening the measurement response time of the electronic scanning valve and the response time of connecting to the back-end digital acquisition for data collection, thereby improving the test efficiency.

[0079] The above solution is only an illustration of a preferred embodiment, but is not limited thereto. When implementing the present invention, appropriate replacement and / or modification can be performed according to user needs.

[0080] The number of devices and processing scales described here are used to simplify the description of the present invention. Applications, modifications and variations of the present invention will be obvious to those skilled in the art.

[0081] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and the embodiments. It can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily realized. Without departing from the general concept defined by the claims and equivalent scopes, the present invention is not limited to the specific details and the illustrations shown and described here.

Claims

1. An electronic scanning valve protection device, characterized in that: include: A protection box, on which a rectangular mounting groove for accommodating the electronic scanning valve is provided; A protective cover disposed on the mounting groove to encapsulate the electronic scanning valve; A measuring rake arranged at the front end of the protection box for measuring airflow parameters at the tail nozzle outlet of the aircraft; Wherein, the front end of the protection box cooperating with the measuring rake is configured to be in a wedge shape, and the wedge angle is less than or equal to 30°; The front end of the protection box is provided with a fixing groove, and the bottom of the measuring rake is provided with a positioning block matched with the fixing groove structure; Wherein, a triangular groove is provided at the bottom of the protection box at a position matching the fixing groove, and the positioning block is connected and fixed to the fixing groove through a first fixing screw hole and a first fixing screw provided on the triangular groove; The protective cover is configured to include two pressing plates symmetrical along the longitudinal axis of the rectangular mounting slot; Each pressing plate has a straight section and an upward section that match the external structure of the protection box in space; The upper surface of the straight section of each pressing plate is provided with a first arc groove, and the first arc grooves on two pressing plates are closed to form a lead-in circular hole for introducing a pressure measuring tube in a measuring rake; The upward section of each cover plate is provided with a downwardly extending buckle plate on the side wall matching the rectangular mounting groove, and the buckle plate is provided with a second arc groove at a position matching the signal line of the electronic scanning valve. The second arc grooves on the two buckle plates form an "n"-shaped wiring groove that can lead out the signal line of the electronic scanning valve when closed.

2. The electronic scanning valve protection device according to claim 1, characterized in that: The inner side wall of the rectangular installation groove is provided with a heat insulation sleeve which is clearance-matched with the electronic scanning valve; Wherein, the thermal insulation sleeve is configured to be made of polytetrafluoroethylene.

3. The electronic scanning valve protection device according to claim 1, characterized in that: The protection box is provided with equal straight sections at the position connected to the front end; The rear end of the straight section is provided with an expansion section which is gradually tilted upwards to match the straight section; A cylindrical section and a conical section are arranged behind the expansion section to lead out the lead wire of the electronic scanning valve; Wherein, the rectangular mounting groove is arranged on the straight section and the expansion section; The conical section is configured with a taper of 1:10 and is connected to the tail strut in the wind tunnel; The center of the cylindrical section is about 20 mm higher than the electronic scanning valve in the longitudinal symmetry plane. A circular hole with a diameter of φ12 mm is opened in the center of the cylindrical section and the conical section to introduce the signal line of the electronic scanning valve into the tail support rod and then connect it to the data acquisition system.

4. The electronic scanning valve protection device according to claim 1, characterized in that: The protective cover and the protective box are provided with second fixing screw holes on the matching sides thereof, so as to connect and fix the protective cover and the protective box through the matching second fixing screws.

5. The electronic scanning valve protection device according to claim 1, characterized in that: Long-staple cotton is arranged inside the protection box and in the holes and grooves on the protection cover to fill the gaps; The combination of the protection box and the protection cover is integrally wrapped and sealed by adhesive tape.

6. A method for using the electronic scanning valve protection device according to any one of claims 1 to 5, characterized in that: include; The positioning block on the measuring rake is embedded into the triangular groove of the protection box, and the two are fixedly connected by the first screw; Connect the pressure measuring tube of the measuring rake to the electronic scanning valve; Embed the electronic scanning valve into the rectangular installation groove, and pass the lead wire of the electronic scanning valve through the central circular holes of the cylindrical section and the conical section; The protective cover is placed on the rectangular installation groove so that the pressure measuring tube of the measuring rake and the signal line of the electronic scanning valve pass through the lead round hole and the wiring groove on the protective cover respectively and are fixed; After filling the gaps inside the protection box and the holes on the protection cover with long-staple cotton, the combination of the protection box and the protection cover is wrapped and sealed as a whole with adhesive tape; The signal line of the electronic scanning valve passing through the central circular holes of the cylindrical section and the conical section is introduced into the tail support rod and connected with the data acquisition system, and the assembly is fixed to the tail support rod.

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