An aircraft engine inlet dust concentration control device and its design method

Abstract

The present application provides an aircraft engine inlet sand and dust concentration control device and its design method, which belong to the field of aircraft engine swallowing test technology. The sand and dust concentration control device includes: a sand barrel; a sand and dust confluence assembly, the top of which is connected to the bottom of the sand barrel and provided with a sand outlet; a sand and dust flow metering assembly, which includes a rotating shaft, a paddle and a sand discharge pipe, the rotating shaft passes through the top wall of the sand barrel, the bottom end of the rotating shaft is connected to the paddle inside the sand barrel, the top end of the sand discharge pipe is connected to the paddle, the sand discharge pipe is hollow, and the side wall of the top end of the sand discharge pipe is provided with a sand discharge outlet, the paddle and the sand discharge pipe are located inside the sand barrel, and the sand discharge pipe extends from the bottom of the sand barrel into the top end of the sand and dust confluence assembly; a sand and dust flow control assembly, the output end of which is connected to the top end of the rotating shaft outside the sand barrel, driving the rotating shaft to rise and fall relative to the sand barrel and driving the rotating shaft to rotate around the axis. Through the processing scheme of the present application, the inlet sand and dust flow is measured to ensure the accuracy of the inlet sand and dust concentration during the engine sand swallowing test.

Description

Technical Field

[0001] The present application relates to the field of aircraft engine swallowing test, and in particular to an aircraft engine inlet sand and dust concentration control device and a design method thereof. Background Art

[0002] When military aircraft operate in harsh environments such as deserts, dense smoke, and fog, their engines often ingest sand and dust particles lifted by wind, aircraft contrails, or otherwise suspended in the air. These highly abrasive particles can erode the thin trailing edges and tips of fan and compressor rotors and stator blades, reducing their efficiency and structural strength. Small sand particles can also melt and adhere to turbine blade surfaces, further impacting turbine efficiency. Dusty environments can also increase engine fuel consumption and maintenance costs, significantly reducing the engine's service life.

[0003] To determine the performance of engines after ingesting sand and dust, countries around the world have conducted research. As early as the 1980s, GE in the United States completed sand ingestion tests on its TF34 and CF6 engines according to the "Test Specification for Sand Erosion Resistance of Engine Blade Materials" (MIL-STD-3033). Rolls-Royce in the United Kingdom conducted sand ingestion tests on its Olympus 593 engine according to NATO standards. Russia also completed sand ingestion tests on its TB2-117 engine according to the corresponding GOST standards. These studies have yielded valuable insights into the sand and dust resistance of aircraft engines, guiding their design and manufacturing with promising results.

[0004] The success or failure of sand ingestion tests determines whether aircraft equipped with these engines are capable of deployment and operation in harsh environments such as deserts, dense smoke, and fog. my country's "General Specifications for Aviation Turbojet and Turbofan Engines" (GJB241A-2010) and "General Specifications for Aviation Turboprop and Turboshaft Engines" (GJB 242A-2018) include sand ingestion tests as a key component of the condition evaluation of new aircraft engines. The "Sand Ingestion Test Requirements for Aviation Turbojet and Turbofan Engines" (GJB2026-94) also stipulates the inlet sand and dust concentration during engine sand ingestion tests.

[0005] Existing technical means cannot directly measure the concentration of sand and dust at the engine inlet when the engine swallows sand and dust. Summary of the Invention

[0006] In view of this, the present application provides an aircraft engine inlet sand and dust concentration control device and a design method thereof, which uses an indirect calculation method to solve the problem that the inlet sand and dust concentration cannot be directly measured during the engine sand swallowing test, thereby ensuring the accuracy of the inlet sand and dust concentration during the engine sand swallowing test.

[0007] On the one hand, the present application provides an aircraft engine inlet dust concentration control device that adopts the following technical solution:

[0008] An aircraft engine inlet dust concentration control device, comprising:

[0009] Sand barrel, storing sand and dust;

[0010] A sand and dust confluence component, the top of which is connected to the bottom of the sand cylinder and the bottom of which is provided with a sand outlet;

[0011] The sand and dust flow metering assembly includes a rotating shaft, a paddle, and a sand discharge pipe. The rotating shaft passes through the top wall of the sand barrel. The bottom end of the rotating shaft is connected to the paddle in the sand barrel. The top end of the sand discharge pipe is connected to the paddle. The sand discharge pipe is hollow. A sand discharge port is provided on the side wall of the top end of the sand discharge pipe. The paddle and sand discharge pipe are located inside the sand barrel. The sand discharge pipe extends from the bottom of the sand barrel into the top end of the sand and dust confluence assembly.

[0012] The sand and dust flow control component has an output end connected to the top end of the rotating shaft outside the sand cylinder, driving the rotating shaft to rise and fall relative to the sand cylinder and driving the rotating shaft to rotate around the axis.

[0013] Optionally, the top wall of the sand barrel is provided with a first mounting hole for the rotating shaft to pass through, the outer wall of the rotating shaft and the inner wall of the first mounting hole are sealedly connected, the bottom wall of the sand barrel is provided with a second mounting hole for the sand discharge pipe to extend out, the outer wall of the sand discharge pipe and the inner wall of the second mounting hole are sealedly connected, the top wall of the sand barrel is provided with an air supply joint connected to the interior of the sand barrel, the bottom wall of the sand barrel is provided with a sand leakage joint connected to the interior of the sand barrel, the side wall of the sand barrel is provided with an observation window, and the top wall of the sand barrel is provided with a secondary flow injection air pressure measuring point.

[0014] Optionally, a diverter connected to an air supply connector is provided on the top wall of the sand cylinder, an air inlet end of the diverter is connected to the air supply connector, and a plurality of circular holes evenly distributed along the circumference are provided on the side wall of the exhaust end of the diverter.

[0015] Optionally, a shaft seal for closing the gap between the rotating shaft and the first mounting hole is provided on the top wall of the sand cylinder, and a shaft seal for closing the gap between the sand discharge pipe and the second mounting hole is provided on the bottom wall of the sand cylinder.

[0016] Optionally, the rib line of the paddle is an involute, the diameter range of the paddle is (130-170) mm, the height range of the paddle is (23-27) mm, and the paddle, the rotating shaft and the sand discharge pipe are coaxially arranged.

[0017] Optionally, the sand and dust convergence assembly includes a horizontal pipe, a vertical pipe and a mainstream induced air pressure measuring point. The top of the vertical pipe is connected to the bottom of the sand cylinder, and the bottom of the vertical pipe is connected to the middle of the horizontal pipe. The horizontal pipe is used to connect to the auxiliary air pipeline of the test bench and the engine inlet sand and dust uniformity control device, and is also used to ensure that the sand and dust follow the mainstream induced air. The mainstream induced air pressure measuring point is installed on the horizontal pipe for monitoring the mainstream induced air pressure.

[0018] Optionally, the sand and dust flow control assembly includes a mounting seat, a lifting mechanism and a rotating mechanism, the lifting mechanism is installed on the mounting seat, the output end of the lifting mechanism is connected to the rotating mechanism to drive the rotating mechanism to lift and lower, and the output shaft of the rotating mechanism is connected to the rotating shaft to drive the rotating shaft to rotate around the axis.

[0019] On the other hand, the present application provides a design method for an aircraft engine inlet dust concentration control device using the following technical solution:

[0020] A design method for an aircraft engine inlet dust concentration control device comprises the following steps:

[0021] Based on the design air mass flow rate under the maximum continuous thrust state of the test engine, complete the overall layout design of the above-mentioned engine inlet sand and dust concentration control device. If the air mass flow rate is greater than 100 kg / s, multiple engine inlet sand and dust concentration control devices are connected in parallel, and multiple sand and dust converging assemblies are connected to the same test bench auxiliary air pipeline and the engine inlet sand and dust uniformity control device. Otherwise, the sand and dust converging assembly of a single engine inlet sand and dust concentration control device is connected to the test bench auxiliary air pipeline and the engine inlet sand and dust uniformity control device.

[0022] Determine the height and inner diameter of the sand barrel, the height of the observation window, the length of the rotating shaft, the length of the sand discharge pipe, the stroke of the lifting mechanism, the diameter of the paddle, and the length of the vertical pipe of the sand and dust confluence assembly;

[0023] Determine the minimum cross-sectional area of ​​the sand discharge port of the sand discharge pipe, the inner and outer diameters of the sand discharge pipe, the height of the paddle, the diameter of the rotating shaft, and the inner diameter of the vertical pipe of the sand and dust confluence assembly;

[0024] Determine the lead, control accuracy of the lifting mechanism and the torque, speed and control accuracy of the rotating mechanism;

[0025] Determine the inner diameter of the horizontal pipe of the sand and dust confluence assembly;

[0026] Conduct joint debugging.

[0027] In summary, this application has the following beneficial technical effects:

[0028] The shaft seal designed in this application seals the gap between the rotating shaft and the first mounting hole of the sand barrel and the gap between the sand discharge pipe and the second mounting hole of the sand barrel, preventing sand and dust in the sand barrel from entering the gap between the shaft and the hole and causing the shaft to get stuck or break, resulting in the sand and dust flow metering component being unable to measure the sand and dust flow.

[0029] The diverter designed in this application introduces the vertically downward secondary flow injection air into the sand cylinder horizontally and evenly, while reducing the flow rate of the secondary flow injection air entering the sand cylinder, preventing the secondary flow injection air from impacting the sand and dust in the sand cylinder at high speed, causing the sand and dust flow metering component to be unable to accurately measure the sand and dust flow.

[0030] The observation window designed in this application is transparent organic glass, and the amount of sand and dust in the sand cylinder is monitored locally in real time visually or remotely in real time via video during calibration or testing, to prevent the sand and dust flow metering component from running empty and being unable to measure the sand and dust flow.

[0031] The aircraft engine inlet sand and dust concentration control device proposed in this application implements the design concept of universality and modularity. A single group in series or multiple groups in parallel can be used to control the inlet sand and dust concentration during sand swallowing tests of aircraft engines with different air flow levels. While the inlet sand and dust concentration meets the requirements of the sand swallowing test, it not only expands the scope of application of the device, but also improves the utilization rate of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0033] Figure 1 This is a schematic diagram of the structure of the aircraft engine inlet dust concentration control device of the present application;

[0034] Figure 2 This is a schematic diagram of the structure of the dust flow control component of the present application;

[0035] Figure 3 This is a structural diagram of the dust flow metering component of the present application;

[0036] Figure 4 It is the sand barrel structure diagram of this application;

[0037] Figure 5 It is a structural diagram of the top wall of the sand tube of the present application;

[0038] Figure 6 This is a structural diagram of the sand and dust storage assembly diverter of the present application;

[0039] Figure 7 This is a structural diagram of the sand barrel of the sand and dust storage component of the present application;

[0040] Figure 8 It is a structural diagram of the bottom wall of the sand cylinder of the present application;

[0041] Figure 9 This is a structural diagram of the sand and dust confluence component of the present application;

[0042] Figure 10 It is the design flow chart of this application.

[0043] Explanation of the accompanying reference numerals: 1. Sand and dust flow control assembly; 2. Sand and dust flow metering assembly; 3. Sand cylinder; 4. Sand and dust convergence assembly; 5. Mounting seat; 6. Lifting mechanism; 7. Connecting seat; 8. Rotating mechanism; 9. Coupling; 10. Rotating shaft; 11. Paddle; 12. Sand discharge pipe; 13. Sand discharge port; 14. Shaft seal; 15. Top wall; 16. Air supply connector; 17. Diverter; 19. Observation window; 20. Pressure plate; 21. Bottom wall; 22. Hourglass connector; 24. First mounting hole; 25. Secondary flow injection air pressure measuring point; 26. Air inlet end; 27. Circular hole; 28. Observation port; 30. Second mounting hole; 31. Horizontal pipe; 32. Vertical pipe; 33. Main flow injection air pressure measuring point. DETAILED DESCRIPTION

[0044] The embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0045] The following describes the embodiments of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, in the absence of conflict, the features in the following embodiments and embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of this application.

[0046] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on this application, it should be understood by those skilled in the art that an aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number of aspects described herein can be used to implement an apparatus and / or practice a method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this apparatus and / or practice this method.

[0047] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application. The illustrations only show components related to the present application and are not drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component can be changed at will, and the component layout type may also be more complicated.

[0048] Additionally, in the following description, specific details are provided to provide a thorough understanding of the examples. However, one skilled in the art will appreciate that the aspects described can be practiced without these specific details.

[0049] An embodiment of the present application provides a device for controlling sand and dust concentration at the inlet of an aircraft engine.

[0050] like Figure 1 As shown, a device for controlling sand and dust concentration in an aircraft engine inlet comprises:

[0051] The sand cylinder 3 stores sand and dust.

[0052] The top of the sand and dust confluence component 4 is connected to the bottom of the sand cylinder 3, and a sand outlet is provided at the bottom.

[0053] like Figure 2 and Figure 3 The sand and dust flow metering assembly 2 includes a rotating shaft 10, a paddle 11 and a sand discharge pipe 12. The rotating shaft 10 passes through the top wall 15 of the sand cylinder 3. The bottom end of the rotating shaft 10 is connected to the paddle 11 inside the sand cylinder 3. The top of the sand discharge pipe 12 is connected to the paddle 11. The sand discharge pipe 12 is hollow. A sand discharge port 13 is provided on the side wall of the top of the sand discharge pipe 12. The paddle 11 and the sand discharge pipe 12 are located inside the sand cylinder 3. The sand discharge pipe 12 extends from the bottom of the sand cylinder 3 into the top of the sand and dust confluence assembly 4.

[0054] The sand dust flow control component 1 has an output end connected to the top of the rotating shaft 10 outside the sand cylinder 3, driving the rotating shaft 10 to rise and fall relative to the sand cylinder 3, and driving the rotating shaft 10 to rotate around the axis.

[0055] When the rotating shaft 10, the paddle 11 and the sand discharge pipe 12 rise and fall under the drive of the sand and dust flow control component 1, the paddle 11 eats the sand and dust in the sand cylinder 3, and the sand and dust flow control component 1 drives the rotating shaft 10 to rotate around the center of the rotating shaft 10, and the paddle 11 and the sand discharge pipe 12 also rotate accordingly. Under the action of centripetal force, the paddle 11 discharges the eaten sand and dust through the sand discharge port 13 of the sand discharge pipe 12, and finally discharges it through the sand and dust confluence component 4, which is used to measure the sand and dust flow entering the engine inlet.

[0056] like Figure 4-Figure 8 As shown, the top wall 15 of the sand barrel 3 is provided with a first mounting hole 24 for the rotating shaft 10 to pass through, and the bottom wall 21 of the sand barrel 3 is provided with a second mounting hole 30 for the sand discharge pipe 12 to extend out. The outer wall of the sand discharge pipe 12 and the inner wall of the second mounting hole 30 are sealedly connected. The top wall 15 of the sand barrel 3 is provided with an air supply joint 16 connected to the interior of the sand barrel 3, and the bottom wall 21 of the sand barrel 3 is provided with a sand leakage joint connected to the interior of the sand barrel 3. The side wall of the sand barrel 3 is provided with an observation window 19, and the top wall 15 of the sand barrel 3 is provided with a secondary flow injection air pressure measuring point 25.

[0057] In one embodiment, the sand barrel 3 has an inner diameter of 150 mm and a height of 280 mm. The top wall 15 of the sand barrel 3 is made of stainless steel. One end of the air supply connector 16 is a G3 / 8 external thread and the other end is a quick connector, which is used to supply secondary flow injection air to the sand barrel 3. The top wall 15 of the sand barrel 3 is provided with a mounting hole for the air supply connector 16. The mounting hole for the air supply connector 16 has an inner diameter of G3 / 8 thread and is used for installing the air supply connector 16. The bottom wall 21 of the sand barrel 3 is made of stainless steel. One end of the sand leakage connector has a G3 / 8 external thread and the other end is a quick connector, which is used to collect residual sand and dust in the sand barrel 3. The bottom wall 21 of the sand barrel 3 is provided with a mounting hole for the sand leakage connector. The mounting hole for the sand leakage connector has an inner diameter of G3 / 8 thread and is used for installing the sand leakage connector. The first mounting hole 24 has an inner diameter of 20 mm, and the second mounting hole 30 has an inner diameter of 20 mm.

[0058] In one embodiment, a through slot is provided on the side wall of the cylinder as an observation port 28, and an observation window 19 made of organic glass is installed in the observation port 28 for local regular or remote real-time monitoring of the amount of sand in the sand cylinder 3. The observation window 19 is pressed against the sand cylinder 3 by a stainless steel pressing plate 20, and the space between the observation window 19 and the observation port 28 is sealed.

[0059] The top wall 15 inside the sand tube 3 is provided with a diverter 17 connected to the air supply connector 16. The air inlet end 26 of the diverter 17 is connected to the air supply connector 16, and the side wall of the exhaust end of the diverter 17 is provided with a plurality of circular holes 27 evenly distributed along the circumference. It is used to horizontally discharge the secondary flow injection air into the sand tube 3. In one embodiment, the diverter 17 is made of stainless steel, and the air inlet of the diverter 17 has an inner diameter of 15mm, an outer diameter of G3 / 8 thread, and a height of 20mm. It is used to vertically introduce the secondary flow injection air. The exhaust port of the diverter 17 is composed of four circular holes 27 with an inner diameter of 8mm, evenly distributed along the circumference, which are used to horizontally discharge the secondary flow injection air into the sand tube 3.

[0060] A shaft seal 14 is provided on the top wall 15 of the sand cylinder 3 to seal the gap between the rotating shaft 10 and the first mounting hole 24. The first mounting hole 24 on the top wall 15 of the sand cylinder 3 and the rotating shaft 10 are softly connected and dynamically sealed by the shaft seal 14. The second mounting hole 30 on the bottom wall 21 of the sand cylinder 3 and the sand and dust confluence assembly 4 are connected by flange bolts and sealed at the end, which are used for storing sand and dust for the engine sand swallowing test, sealing the sand and dust flow metering assembly 2, and monitoring the secondary flow injection air pressure.

[0061] The rib line of the pick 11 is an involute, the diameter range of the pick 11 is (130-170) mm, the height range of the pick 11 is (23-27) mm, and the pick 11, the rotating shaft 10 and the sand discharge pipe 12 are coaxially arranged.

[0062] In one embodiment, the rotating shaft 10 has a diameter of 20 mm and a length of 300 mm, constructed from high-strength carbon steel with a wear-resistant surface treatment. It securely connects the dust flow control assembly 1 to the dust flow metering assembly 2. The paddle 11, with an involute rib line, has a diameter of 150 mm and a height of 25 mm, and is formed from a single piece of high-strength carbon steel. The sand discharge pipe 12 has an outer diameter of 20 mm and an inner diameter of 14 mm, constructed from high-strength carbon steel with a wear-resistant surface treatment. It is used to remove dust swept by the paddle 11 into the sand discharge port 13 of the sand discharge pipe 12, thereby metering the dust flow entering the engine inlet.

[0063] like Figure 9 As shown, the sand and dust confluence assembly 4 includes a horizontal pipe 31, a vertical pipe 32 and a mainstream induced air pressure measuring point 33. The top of the vertical pipe 32 is connected to the bottom of the sand cylinder 3, and the bottom of the vertical pipe 32 is connected to the middle of the horizontal pipe 31. The horizontal pipe 31 is used to connect with the auxiliary air pipeline of the test bench and the engine inlet sand and dust uniformity control device, and is also used for the full follow-up of sand and dust with the mainstream induced air. The mainstream induced air pressure measuring point 33 is installed on the horizontal pipe 31 for monitoring the mainstream induced air pressure.

[0064] In one embodiment, the vertical tube 32 has an inner diameter of 30 mm, and the vertical tube 32 is connected to the second mounting hole 30 on the bottom wall 21 of the sand cylinder 3. The top of the vertical tube 32 is sealed and fixedly connected to the bottom wall 21 of the sand cylinder 3 around the second mounting hole 30, and the inner diameter of the horizontal tube 31 is 100 mm.

[0065] The dust flow control assembly 1 includes a mounting base 5, a lifting mechanism 6 and a rotating mechanism 8. The lifting mechanism 6 is mounted on the mounting base 5. The output end of the lifting mechanism 6 is connected to the rotating mechanism 8 via a connecting base 7, driving the rotating mechanism 8 to rise and fall. The output shaft of the rotating mechanism 8 is connected to the rotating shaft 10 via a coupling 9, driving the rotating shaft 10 to rotate around the axis. The lifting mechanism 6 can be a cylinder, the output shaft of the cylinder is connected to the housing of the rotating mechanism 8, and the output shaft of the cylinder is vertically retractable. The lifting mechanism 6 can also be a motor connected to a ball screw, the nut of the ball screw serves as the output end of the lifting mechanism 6, the screw of the ball screw is vertically arranged, and the motor drives the screw of the ball screw to rotate.

[0066] The lifting mechanism and rotating mechanism of this application are independent structures. The lifting mechanism is independently controlled by a high-precision PLC. The control variables are speed and distance. During calibration or testing, the feed speed and distance of the sand and dust flow metering assembly are controlled locally manually or remotely and automatically. Assisted by a photoelectric limit switch, the sand and dust concentration can be safely and accurately controlled. The rotating mechanism is independently controlled by a high-precision PLC. The control variable is speed. During calibration or testing, the rotation speed of the sand and dust flow metering assembly is controlled locally manually or remotely and automatically. Assisted by a secondary flow to induced air, the sand and dust concentration can be effectively and accurately controlled.

[0067] The embodiments of the present application also disclose a design method for an aircraft engine inlet sand and dust concentration control device.

[0068] like Figure 10 As shown, a design method for an aircraft engine inlet dust concentration control device includes the following steps:

[0069] S1. Overall layout design. Complete the overall layout design of the above-mentioned engine inlet dust concentration control device based on the design air mass flow rate Wse (kg / s) under the maximum continuous thrust state of the test engine. If Wse is greater than 100 kg / s, multiple engine inlet dust concentration control devices are connected in parallel, and multiple dust merging assemblies are connected to the same test bench auxiliary air pipeline and the engine inlet dust uniformity control device. Otherwise, the dust merging assembly of a single engine inlet dust concentration control device is connected to the test bench auxiliary air pipeline and the engine inlet dust uniformity control device.

[0070] S2. Design of main parts and components: S2.1 Determine the height and inner diameter of the sand barrel, the height of the observation window, the length of the rotating shaft, the length of the sand discharge pipe, the stroke of the lifting mechanism, the diameter of the paddle, and the length of the vertical pipe of the sand and dust confluence assembly; S2.2 Determine the minimum cross-sectional area of ​​the sand discharge port of the sand discharge pipe, the inner and outer diameters of the sand discharge pipe, the height of the paddle, the diameter of the rotating shaft, and the inner diameter D of the vertical pipe of the sand and dust confluence assembly. i_czg ; S2.3. Determine the lead, control accuracy of the lifting mechanism and the torque, speed and control accuracy of the rotating mechanism; S2.4. Determine the inner diameter of the horizontal pipe of the sand and dust confluence assembly.

[0071] S3. Design of other parts and components.

[0072] S4. Perform joint debugging.

[0073] In one embodiment,

[0074] S2.1 includes the following: se , determine the design air volume flow rate V under the maximum continuous thrust state of the test engine se (m 3 / s); according to V se , determine the sand volume V used in the test engine during the first stage of sand swallowing s (cm 3 ); According to V s , determine the sand cylinder volume V st (cm 3 ); According to V st , determine the sand cylinder height H st (mm), inner diameter D st (mm); according to H st , determine the observation window height H gcc (mm), shaft length L bpz (mm), sand discharge pipe length L psg (mm), lifting mechanism stroke S (mm); according to D st , determine the pick diameter D bp (mm); according to L psg , determine the length L of the vertical pipe of the sand and dust confluence assembly czg (mm).

[0075] S2.2 includes V se , determine the test engine sand swallowing flow rate W s (g / s); according to W s , determine the minimum cross-sectional area A of the sand discharge port of the sand discharge pipe psk (mm 2 ); According to A psk , determine the inner diameter D of the sand discharge pipe i_psg (mm), outer diameter D o_psg (mm) and pick height H bp(mm); according to D o_psg , determine the shaft diameter D bpz (mm) and the inner diameter D of the vertical pipe of the sand and dust confluence assembly i_spg (mm).

[0076] S2.3 includes the following: s , determine the lead s (mm) and control accuracy of the lifting mechanism; according to W s , determine the torque T (N·m), speed n (r / min) and control accuracy of the rotating mechanism.

[0077] S2.4 includes the following: cl and P zl , determine the inner diameter D of the horizontal pipe of the sand and dust confluence assembly spg (mm).

[0078] In one embodiment, S3, other parts and components design includes: shaft seal at 0.5kPa<P cl -P zl Under the condition of <1.5kPa, ensure that the rotating shaft and the sand discharge pipe are well sealed during spiral motion; the total flow area of ​​the multiple circular holes in the diverter is larger than the flow area of ​​the air inlet end; the observation window must be able to clearly observe the amount of sand stored in the sand cylinder; the first mounting hole must ensure that the rotating shaft can rotate flexibly and without obstruction; the second mounting hole must ensure that the sand discharge pipe can rotate flexibly and without obstruction.

[0079] S4, joint debugging includes: software and hardware preparation and static inspection of the engine inlet sand and dust concentration control device; reliability inspection of the engine inlet sand and dust concentration control device; function and performance inspection of the engine inlet sand and dust concentration control device.

[0080] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A design method for an aircraft engine inlet dust concentration control device, characterized in that: The steps include: Based on the designed air mass flow rate at the maximum continuous thrust state of the test engine, the overall layout design of the engine inlet dust concentration control device is completed. The engine inlet dust concentration control device includes: Sand barrel, storing sand and dust; A sand and dust confluence component, the top of which is connected to the bottom of the sand cylinder and the bottom of which is provided with a sand outlet; The sand and dust flow metering assembly includes a rotating shaft, a paddle, and a sand discharge pipe. The rotating shaft passes through the top wall of the sand barrel. The bottom end of the rotating shaft is connected to the paddle in the sand barrel. The top end of the sand discharge pipe is connected to the paddle. The sand discharge pipe is hollow. A sand discharge port is provided on the side wall of the top end of the sand discharge pipe. The paddle and sand discharge pipe are located inside the sand barrel. The sand discharge pipe extends from the bottom of the sand barrel into the top end of the sand and dust confluence assembly. The sand dust flow control component has an output end connected to the top of the rotating shaft outside the sand barrel, driving the rotating shaft to rise and fall relative to the sand barrel and drive the rotating shaft to rotate around the axis; If the air mass flow rate is greater than 100 kg / s, multiple engine inlet dust concentration control devices are connected in parallel, and multiple dust converging assemblies are connected to the same test bench auxiliary air pipeline and the engine inlet dust uniformity control device; otherwise, the dust converging assembly of a single engine inlet dust concentration control device is connected to the test bench auxiliary air pipeline and the engine inlet dust uniformity control device; Determine the height and inner diameter of the sand barrel, the height of the observation window, the length of the rotating shaft, the length of the sand discharge pipe, the stroke of the lifting mechanism, the diameter of the paddle, and the length of the vertical pipe of the sand and dust confluence assembly; Determine the minimum cross-sectional area of ​​the sand discharge port of the sand discharge pipe, the inner and outer diameters of the sand discharge pipe, the height of the paddle, the diameter of the rotating shaft, and the inner diameter of the vertical pipe of the sand and dust confluence assembly; Determine the lead, control accuracy of the lifting mechanism and the torque, speed and control accuracy of the rotating mechanism; Determine the inner diameter of the horizontal pipe of the sand and dust confluence assembly; Conduct joint debugging.

2. The design method of the aircraft engine inlet dust concentration control device according to claim 1 is characterized in that: The top wall of the sand barrel is provided with a first mounting hole for the rotating shaft to pass through, the outer wall of the rotating shaft is sealedly connected to the inner wall of the first mounting hole, the bottom wall of the sand barrel is provided with a second mounting hole for the sand discharge pipe to extend out, the outer wall of the sand discharge pipe is sealedly connected to the inner wall of the second mounting hole, the top wall of the sand barrel is provided with an air supply joint connected to the interior of the sand barrel, the bottom wall of the sand barrel is provided with a sand leakage joint connected to the interior of the sand barrel, the side wall of the sand barrel is provided with an observation window, and the top wall of the sand barrel is provided with a secondary flow injection air pressure measuring point.

3. The design method of the aircraft engine inlet dust concentration control device according to claim 2 is characterized in that: The top wall of the sand cylinder is provided with a diverter connected to the air supply joint, the air inlet end of the diverter is connected to the air supply joint, and the side wall of the exhaust end of the diverter is provided with a plurality of circular holes evenly distributed along the circumferential direction.

4. The design method of the aircraft engine inlet dust concentration control device according to claim 2 is characterized in that: A shaft seal for closing the gap between the rotating shaft and the first mounting hole is provided on the top wall of the sand cylinder, and a shaft seal for closing the gap between the sand discharge pipe and the second mounting hole is provided on the bottom wall of the sand cylinder.

5. The design method of the aircraft engine inlet dust concentration control device according to claim 1 is characterized in that: The rib line of the paddle is an involute, the diameter range of the paddle is (130-170) mm, the height range of the paddle is (23-27) mm, and the paddle, the rotating shaft and the sand discharge pipe are coaxially arranged.

6. The design method of the aircraft engine inlet dust concentration control device according to claim 1, characterized in that: The sand and dust convergence assembly includes a horizontal pipe, a vertical pipe and a mainstream induced air pressure measuring point. The top of the vertical pipe is connected to the bottom of the sand cylinder, and the bottom of the vertical pipe is connected to the middle of the horizontal pipe. The horizontal pipe is used to connect with the auxiliary air pipeline of the test bench and the engine inlet sand and dust uniformity control device. It is also used to ensure that the sand and dust follow the mainstream induced air. The mainstream induced air pressure measuring point is installed on the horizontal pipe for monitoring the mainstream induced air pressure.

7. The design method of the aircraft engine inlet dust concentration control device according to claim 1, characterized in that: The sand and dust flow control assembly includes a mounting seat, a lifting mechanism and a rotating mechanism. The lifting mechanism is installed on the mounting seat. The output end of the lifting mechanism is connected to the rotating mechanism to drive the rotating mechanism to rise and fall. The output shaft of the rotating mechanism is connected to the rotating shaft to drive the rotating shaft to rotate around the axis.

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