Double-duct compression component flow measurement system and method

Abstract

The invention relates to the technical field of double-duct aero-engine compression component testing, and discloses a double-duct compression component flow measuring system and method.An inner duct and an outer duct of a double-duct compression component are exhausted separately, and a pressure measuring probe is arranged in an outer duct exhaust pipe communicated with an outer duct flow channel of a compression component tester; a flow meter is arranged in the inner duct exhaust pipe communicated with the inner duct flow channel of the compression part test piece; a flow pipe is arranged at the front end of a first airflow pipeline connected between an air inlet chamber and a pressure stabilizing box, and the airtight performance of the double-duct compression component flow measuring system is judged according to the relation among a first flow value of the flow pipe, second flow of a flow meter and third flow converted through a pressure measuring probe. Finally, a flow test value meeting the air tightness requirement is output, accurate measurement of test data is ensured, the reliability of the test data is improved, and therefore support is provided for subsequent double-duct aero-engine whole machine test and component optimization.

Description

Technical Field

[0001] The invention relates to the technical field of dual-duct aircraft engine compression component testing, and discloses a dual-duct compression component flow measurement system and method. Background Art

[0002] In order to explore the performance of dual-ducted aircraft engines, relevant tests of dual-ducted aircraft engines are essential, and the flow measurement of the dual-ducted fan / compressor, which is a key component of the engine, is crucial in the test verification process. The structural design of the intake system, the sealing method of the test system, and the accuracy of the flow measurement device will directly affect the test data, and thus affect the performance evaluation of the dual-ducted aircraft engine.

[0003] For the double-duct test piece, due to the large air intake flow, air leakage is very likely to occur at the connection with the test piece, so it is very important to seal the front and rear ends well. The airflow is exhausted to the inner and outer ducts separately at the outlet of the test piece, which increases the difficulty of sealing. In addition, during the test, the high exhaust temperature and the vibration of the test piece will affect the sealing method, resulting in system leakage and inaccurate test data collection. Summary of the invention

[0004] The object of the present invention is to provide a dual-duct compression component flow measurement system and method, which can ensure accurate measurement of test data and improve the reliability of the test data.

[0005] In order to achieve the above technical effects, the technical solution adopted by the present invention is:

[0006] A double-duct compression component flow measurement system, comprising:

[0007] An air inlet chamber, the air inlet chamber being used to provide a test air flow;

[0008] A pressure stabilizing box, the inlet end of which is connected to the outlet end of the air inlet chamber through a first airflow pipe, a flow tube is provided at the inlet end of the first airflow pipe, and the flow tube is used to measure the airflow rate entering the first airflow pipe;

[0009] A compression component test piece, wherein the compression component test piece is a double-duct structure with an inner duct and an outer duct, and the compression component test piece is connected to an outlet end of the pressure stabilizing box through a second airflow duct;

[0010] An exhaust volute, wherein an outer exhaust passage and an inner exhaust passage are arranged in the exhaust volute, wherein the outer exhaust passage is connected to the outlet end of the outer flow passage, and the inner exhaust passage is connected to the outlet end of the inner flow passage;

[0011] An exhaust pipe, the exhaust pipe comprising an outer exhaust pipe and an inner exhaust pipe, the inner exhaust pipe is connected to the inner exhaust channel, a flow meter is arranged in the inner exhaust pipe; the outer exhaust pipe is connected to the outer exhaust channel, a pressure probe is arranged in the outer exhaust pipe;

[0012] A power drive system is used to drive the internal rotor of the compression component test piece to rotate.

[0013] Furthermore, the exhaust volute is provided with sealing grooves at positions corresponding to the outlet end of the inner profile of the outer duct, the outlet end of the outer profile of the inner duct, and the outlet end of the inner profile of the inner duct, respectively. The outlet end of the inner profile of the outer duct, the outlet end of the outer profile of the inner duct, and the outlet end of the inner profile of the inner duct are respectively inserted into the corresponding sealing grooves, and the axial clearance between the outlet end of the inner profile of the outer duct, the outlet end of the outer profile of the inner duct, and the outlet end of the inner profile of the inner duct and the axial bottom surface of the corresponding sealing groove is greater than or equal to a preset spacing threshold, and the preset spacing threshold is based on It is obtained by analysis, wherein ΔL is the preset spacing threshold, C is the test safety factor, the value range of C is 1.1 to 1.5, α is the expansion coefficient of the compression component test piece, L is the initial axial length of the compression component test piece, ΔT is the difference between the temperature of the compression component test piece under the test conditions and the room temperature, f is the vibration frequency of the compression component test piece during the test, u is the vibration acceleration, F is the axial force exerted on the compression component test piece during the test, E is the elastic modulus of the material used for the compression component test piece, and A is the cross-sectional area of ​​the drive shaft of the compression component test piece.

[0014] Furthermore, an annular asbestos packing is arranged between the outlet end of the inner profile of the outer duct, the outlet end of the outer profile of the inner duct, the outlet end of the inner profile of the inner duct and the axial bottom surface of the corresponding sealing groove, and a spring is arranged between the asbestos packing and the axial bottom surface of the corresponding sealing groove, and the elastic force of the spring is greater than the friction force between the asbestos packing and the upper and lower walls of the sealing groove when the asbestos packing is completely sealed; the elastic coefficient of the spring has a value range of Where Δx1 is the axial displacement of the compression component test piece caused by the pre-compression force F1, D is the thickness of the asbestos packing, and the value range of D is x is the contact surface width between the asbestos packing and the sealing groove, μ is the friction coefficient between the asbestos packing and the sealing groove, k s is the elastic coefficient of asbestos packing, and H is the radial height of the sealing groove.

[0015] Furthermore, the air inlet chamber includes a horizontal section and a vertical section, the horizontal section is connected to the vertical section; the outlet end of the air inlet chamber is arranged at the end of the horizontal section away from the vertical section; the air inlet chamber is provided with a guide vane at the corner connection between the horizontal section and the vertical section, and the guide vane includes a plurality of arc guide blades arranged evenly at intervals.

[0016] Furthermore, the chord length of the guide blades ranges from 1.3 to 1.5 m, the number of guide blades ranges from 8 to 10, the pitch ranges from 0.6 to 0.7 m, and the guide blade paving angle ranges from 40° to 45°.

[0017] Furthermore, a rectifying net is arranged in the horizontal section, and the rectifying net is arranged at a downstream position of the guide vane.

[0018] Furthermore, the inlet end of the first airflow duct is provided with an expansion section with a smoothly increasing diameter, the end of the expansion section close to the air inlet chamber extends into the air inlet chamber and is coaxially connected with the flow tube, and a rubber sealing plate is provided at the circumferential position where the outer wall of the expansion section contacts the air inlet chamber.

[0019] In order to achieve the above technical effects, the present invention also provides a dual-duct compression component flow measurement method, which is based on the dual-duct compression component flow measurement system and includes:

[0020] Start the power drive system to drive the rotor inside the compression component test piece to rotate;

[0021] After the flow tube measurement data at the inlet end of the first air flow tube is stable, the first flow value of the flow tube is read, and the second flow of the flow meter in the inner exhaust pipe and the pressure value of the pressure measuring probe in the outer exhaust pipe are read respectively;

[0022] According to the pressure value of the pressure measuring probe, a third flow rate in the outer exhaust pipe is obtained by analyzing the flow rate formula;

[0023] If the first flow value data is the sum of the second flow and the third flow, the first flow data is output as the flow test value of the dual-duct compression component. Otherwise, the airtight performance of the flow measurement system of the dual-duct compression component is checked until the first flow value data is the sum of the second flow and the third flow, and then the first flow data is output as the flow test value of the dual-duct compression component.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention exhausts the inner and outer ducts of the dual-duct compression component separately, and arranges a pressure measuring probe in the outer duct exhaust pipe connected to the outer duct flow channel of the compression component tester, and arranges a flow meter in the inner duct exhaust pipe connected to the inner flow channel of the compression component test piece; a flow tube is arranged at the front end of the first airflow duct connecting the air intake chamber and the pressure stabilizing box, and the airtight performance of the dual-duct compression component flow measurement system is judged according to the relationship between the first flow value of the flow tube, the second flow of the flow meter and the third flow converted by the pressure measuring probe, and finally outputs a flow test value that meets the airtightness requirements, thereby ensuring accurate measurement of test data and improving the reliability of test data, thereby providing support for subsequent dual-duct aircraft engine whole machine testing and component optimization. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the structure of the flow measurement system of the double-duct compression component in the embodiment;

[0026] Figure 2 Schematic diagram of the connection between the compression component test piece and the exhaust turbine in the embodiment;

[0027] Figure 3 A schematic diagram of the connection relationship between the air inlet chamber and the expansion section in the embodiment;

[0028] Among them, 1. air intake chamber; 2. pressure stabilizing box; 3. first air flow duct; 301. expansion section; 4. flow tube; 5. compression component test piece; 501. inner flow channel; 502. outer flow channel; 6. second air flow duct; 7. exhaust volute; 701. outer exhaust channel; 702. inner exhaust channel; 703. sealing groove; 8. outer exhaust pipe; 9. inner exhaust pipe; 10. flow meter; 11. pressure probe; 12. power drive system; 13. asbestos packing; 14. spring; 15. guide vane; 16. rectifier net; 17. rubber sealing plate. DETAILED DESCRIPTION

[0029] The present invention is further described in detail below in conjunction with the embodiments and drawings. However, it should not be understood that the scope of the above subject matter of the present invention is limited to the following embodiments, and all technologies realized based on the content of the present invention belong to the scope of the present invention.

[0030] Example

[0031] See also Figure 1-Figure 3 , a double-duct compression component flow measurement system, comprising:

[0032] An air inlet chamber 1, wherein the air inlet chamber 1 is used to provide a test air flow;

[0033] A pressure stabilizing box 2, the inlet end of which is connected to the outlet end of the air inlet chamber 1 through a first airflow pipe 3, a flow tube 4 is provided at the inlet end of the first airflow pipe, and the flow tube 4 is used to measure the airflow rate entering the first airflow pipe 3;

[0034] A compression component test piece 5, wherein the compression component test piece 5 is a double-duct structure with an inner duct 501 and an outer duct 502, and the compression component test piece 5 is connected to the outlet end of the pressure stabilizing tank 2 through a second airflow duct 6;

[0035] An exhaust volute 7, wherein an outer exhaust passage 701 and an inner exhaust passage 702 are provided in the exhaust volute 7, wherein the outer exhaust passage 701 is communicated with the outlet end of the outer flow passage 502, and the inner exhaust passage 702 is communicated with the outlet end of the inner flow passage 501;

[0036] An exhaust pipe, the exhaust pipe comprising an outer exhaust pipe 8 and an inner exhaust pipe 9, the inner exhaust pipe 9 is connected to the inner exhaust channel 702, a flow meter 10 is arranged in the inner exhaust pipe 9; the outer exhaust pipe 8 is connected to the outer exhaust channel 701, a pressure probe 11 is arranged in the outer exhaust pipe 8;

[0037] The power driving system 12 is used to drive the internal rotor of the compression component test piece 5 to rotate.

[0038] In this embodiment, the operation method of the dual-duct compression component flow measurement system is as follows:

[0039] Start the power drive system 12 to drive the internal rotor of the compression component test piece 5 to rotate;

[0040] After the measurement data of the flow tube 4 at the inlet end of the first air flow pipe is stable, the first flow value of the flow tube 4 is read, and the second flow of the flow meter 10 in the inner exhaust pipe 9 and the pressure value of the pressure measuring probe 11 in the outer exhaust pipe 8 are read respectively;

[0041] According to the pressure value of the pressure measuring probe 11, a third flow rate in the outer exhaust pipe 8 is obtained by analyzing the flow rate formula;

[0042] If the first flow value data is the sum of the second flow and the third flow, the first flow data is output as the flow test value of the dual-duct compression component. Otherwise, the airtight performance of the flow measurement system of the dual-duct compression component is checked until the first flow value data is the sum of the second flow and the third flow, and then the first flow data is output as the flow test value of the dual-duct compression component.

[0043] In this embodiment, the inner and outer ducts of the dual-duct compression component are exhausted separately, and a pressure probe 11 is set in the outer duct exhaust pipe 8 connected to the outer duct flow channel 502 of the compression component tester, and a flow meter 10 is set in the inner duct exhaust pipe 9 connected to the inner flow channel 501 of the compression component test piece 5; a flow tube 4 is set at the front end of the first airflow duct 3 connecting the air intake chamber 1 and the pressure stabilizing box 2, and the airtight performance of the dual-duct compression component flow measurement system is judged according to the relationship between the first flow value of the flow tube 4, the second flow of the flow meter 10 and the third flow converted by the pressure probe 11, and finally the flow test value that meets the airtightness requirements is output, thereby ensuring the accurate measurement of the test data and improving the reliability of the test data, thereby providing support for subsequent dual-duct aircraft engine whole machine testing and component optimization.

[0044] During the installation of the compression component test piece 5 on the platform, an axial gap needs to be reserved between the compression component test piece 5 and the exhaust volute 7; if the gap is too large, the sealing effect is poor, resulting in inaccurate flow measurement; if the gap is too small, friction will occur between the test piece and the tester, causing damage. In the present embodiment, the exhaust volute 7 is provided with sealing grooves 703 at positions corresponding to the inner surface outlet end of the outer duct 502, the outer surface outlet end of the inner duct 501, and the inner surface outlet end of the inner duct 501, respectively. The inner surface outlet end of the outer duct 502, the outer surface outlet end of the inner duct 501, and the inner surface outlet end of the inner duct 501 are respectively inserted into the corresponding sealing grooves 703, and the axial gap between the inner surface outlet end of the outer duct 502, the outer surface outlet end of the inner duct 501, and the inner surface outlet end of the inner duct 501 and the corresponding axial bottom surface of the sealing groove 703 is greater than or equal to a preset spacing threshold, and the preset spacing threshold is determined according to the preset spacing threshold. It is obtained through analysis, wherein ΔL is the preset spacing threshold, C is the test safety factor, the value range of C is 1.1 to 1.5, α is the expansion coefficient of the compression component test piece 5, L is the initial axial length of the compression component test piece, Δt is the difference between the temperature of the compression component test piece 5 under the test conditions and the room temperature, f is the vibration frequency of the compression component test piece 5 during the test, u is the vibration acceleration, F is the axial force exerted on the compression component test piece 5 during the test, E is the elastic modulus of the material used for the compression component test piece 5, and A is the cross-sectional area of ​​the drive shaft of the compression component test piece 5.

[0045] In addition, an annular asbestos packing 13 is provided between the inner surface outlet end of the outer duct 502, the outer surface outlet end of the inner duct 501, the inner surface outlet end of the inner duct 501 and the corresponding axial bottom surface of the sealing groove 703, and a spring 14 is provided between the asbestos packing 13 and the corresponding axial bottom surface of the sealing groove 703.

[0046] The maximum compression amount T of the spring 14 must satisfy: T>Δx1-D+x+ΔLmax, that is, the sum of the deformation amount Δx1-D+x of the spring when the asbestos packing 13 is completely sealed and the maximum value ΔLmax of the preset spacing threshold during the test. Selection of asbestos packing 13: When the asbestos packing 13 is completely sealed, ensure that the contact surface width x of the asbestos packing 13 and the sealing groove 703 is greater than D / 2. At this time, the cross-section of the asbestos packing 13 is compressed into a rectangle. It can be known from the equal area that Therefore, the thickness diameter D of asbestos packing 13 ranges from Therefore, the elastic force of the spring 14 is greater than the friction between the upper and lower walls of the sealing groove 703 when the asbestos packing 13 is completely sealed, so as to avoid the asbestos packing 13 from getting stuck; and is less than the pre-compression force F1 when the asbestos packing 13 is completely sealed, so as to prevent the asbestos packing 13 from being damaged. The elastic coefficient of the spring 14 has a value range of Where Δx1 is the axial displacement of the compression component test piece caused by the pre-compression force F1, D is the thickness of the asbestos packing 13, and the value range of D is x is the contact surface width between the asbestos packing 13 and the sealing groove 703, μ is the friction coefficient between the asbestos packing 13 and the sealing groove 703, k s is the elastic coefficient of the asbestos packing 13 , and H is the radial height of the sealing groove 703 .

[0047] In this embodiment, the pre-compression force is to use the retaining ring on the test piece to press the asbestos packing 13 when the test piece is installed to ensure complete sealing, and the axial displacement of the retaining ring can be measured. The characteristic curve of the pre-compression force and the axial displacement is generated on the computer through the data acquisition system. When the pre-compression force is continuously increased to F1 until the axial displacement no longer changes, it indicates that the packing is completely compacted and the cross section changes from a circle to a rectangle. At this time, the axial displacement value corresponding to the pre-compression force F1 on the characteristic curve is Δx1.

[0048] When the air inlet chamber 1 is placed horizontally, it can not only reduce the pressure loss of the airflow caused by the curved flow channel in the pipeline, but also avoid turbulence of the airflow at the corner of the pipeline, so that the incoming flow is more stable. However, a single horizontal air inlet chamber 1 will require too large a horizontal distance of the air inlet chamber 1, resulting in poor system structure. Therefore, the air inlet chamber 1 described in this embodiment includes a horizontal section and a vertical section, and the horizontal section is connected to the vertical section; the outlet end of the air inlet chamber 1 is arranged at the end of the horizontal section away from the vertical section; the air inlet chamber 1 is provided with a guide vane 15 at the corner connection between the horizontal section and the vertical section, and the guide vane 15 includes a plurality of arc guide blades arranged evenly at intervals, and a radial layout is adopted to save space while achieving large air intake.

[0049] In this embodiment, the chord length of the guide vane is in the range of 1.3-1.5m, the number of guide vanes is in the range of 8-10, the grid pitch is in the range of 0.6-0.7m, and the guide vane paving angle is in the range of 40°-45°, which can effectively improve the eccentricity of airflow and make the inlet closer to uniform air intake.

[0050] In this embodiment, a rectifier net 16 is provided in the horizontal section, and the rectifier net is provided downstream of the guide vane 15. The rectifier net 16 can not only make the incoming flow velocity distribution more uniform, but also filter out impurities in the intake air to meet the test intake requirements.

[0051] In this embodiment, the inlet end of the first airflow duct 3 is provided with an expansion section 301 with a smoothly enlarged diameter, the end of the expansion section 301 close to the air inlet chamber 1 extends into the air inlet chamber 1 and is coaxially connected with the flow tube 4, and a rubber sealing plate 17 is provided at the circumferential position where the outer wall of the expansion section 301 contacts the air inlet chamber 1. The sealing performance of the double-duct compression component flow measurement system is further improved, and the problem of dust and impurities at the test site flowing back into the air inlet chamber 1 and affecting the air intake environment can be avoided.

[0052] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A dual-duct compression component flow measurement system, characterized in that: include: An air inlet chamber, the air inlet chamber being used to provide a test air flow; A pressure stabilizing box, the inlet end of which is connected to the outlet end of the air inlet chamber through a first airflow pipe, a flow tube is provided at the inlet end of the first airflow pipe, and the flow tube is used to measure the airflow rate entering the first airflow pipe; A compression component test piece, wherein the compression component test piece is a double-duct structure with an inner duct and an outer duct, and the compression component test piece is connected to an outlet end of the pressure stabilizing box through a second airflow duct; An exhaust volute, wherein an outer exhaust passage and an inner exhaust passage are arranged in the exhaust volute, wherein the outer exhaust passage is connected to the outlet end of the outer flow passage, and the inner exhaust passage is connected to the outlet end of the inner flow passage; An exhaust pipe, the exhaust pipe comprising an outer exhaust pipe and an inner exhaust pipe, the inner exhaust pipe is connected to the inner exhaust channel, a flow meter is arranged in the inner exhaust pipe; the outer exhaust pipe is connected to the outer exhaust channel, a pressure probe is arranged in the outer exhaust pipe; A power drive system is used to drive the internal rotor of the compression component test piece to rotate.

2. The dual-duct compression component flow measurement system according to claim 1, characterized in that: The exhaust volute is respectively provided with sealing grooves at positions corresponding to the outlet end of the inner profile of the outer duct, the outlet end of the outer profile of the inner duct, and the outlet end of the inner profile of the inner duct. The outlet end of the inner profile of the outer duct, the outlet end of the outer profile of the inner duct, and the outlet end of the inner profile of the inner duct are respectively inserted into the corresponding sealing grooves, and the axial clearance between the outlet end of the inner profile of the outer duct, the outlet end of the outer profile of the inner duct, and the outlet end of the inner profile of the inner duct and the axial bottom surface of the corresponding sealing groove is greater than or equal to a preset spacing threshold, and the preset spacing threshold is based on It is obtained by analysis, wherein ΔL is the preset spacing threshold, C is the test safety factor, the value range of C is 1.1 to 1.5, α is the expansion coefficient of the compression component test piece, L is the initial axial length of the compression component test piece, ΔT is the difference between the temperature of the compression component test piece under the test conditions and the room temperature, f is the vibration frequency of the compression component test piece during the test, u is the vibration acceleration, F is the axial force exerted on the compression component test piece during the test, E is the elastic modulus of the material used for the compression component test piece, and A is the cross-sectional area of ​​the drive shaft of the compression component test piece.

3. The dual-duct compression component flow measurement system according to claim 1, characterized in that: An annular asbestos packing is also arranged between the outlet end of the inner profile of the outer duct, the outlet end of the outer profile of the inner duct, the outlet end of the inner profile of the inner duct and the axial bottom surface of the corresponding sealing groove. A spring is arranged between the asbestos packing and the axial bottom surface of the corresponding sealing groove. The elastic force of the spring is greater than the friction force between the asbestos packing and the upper and lower walls of the sealing groove when the asbestos packing is completely sealed; the elastic coefficient of the spring has a value range of Where Δx1 is the axial displacement of the compression component test piece caused by the pre-compression force F1, D is the thickness of the asbestos packing, and the value range of D is x is the contact surface width between the asbestos packing and the sealing groove, μ is the friction coefficient between the asbestos packing and the sealing groove, k s is the elastic coefficient of asbestos packing, and H is the radial height of the sealing groove.

4. The dual-duct compression component flow measurement system according to claim 1, characterized in that: The air inlet chamber includes a horizontal section and a vertical section, the horizontal section is connected to the vertical section; the outlet end of the air inlet chamber is arranged at the end of the horizontal section away from the vertical section; the air inlet chamber is provided with a guide vane at the corner connection between the horizontal section and the vertical section, and the guide vane includes a plurality of arc guide vanes arranged evenly at intervals.

5. The dual-duct compression component flow measurement system according to claim 4, characterized in that: The chord length of the guide blades ranges from 1.3 to 1.5 m, the number of guide blades ranges from 8 to 10, the grid pitch ranges from 0.6 to 0.7 m, and the guide blade paving angle ranges from 40° to 45°.

6. The dual-duct compression component flow measurement system according to claim 1, characterized in that: A rectifying net is arranged in the horizontal section, and the rectifying net is arranged at a downstream position of the guide vane.

7. The dual-duct compression component flow measurement system according to claim 1, characterized in that: The inlet end of the first airflow duct is provided with an expansion section with a smoothly increasing diameter. The end of the expansion section close to the air inlet chamber extends into the air inlet chamber and is coaxially connected with the flow tube. A rubber sealing plate is provided at the circumferential position where the outer wall of the expansion section contacts the air inlet chamber.

8. A method for measuring flow of a dual-duct compression component, the method being based on the dual-duct compression component flow measurement system of claim 1, characterized in that: include: Start the power drive system to drive the rotor inside the compression component test piece to rotate; After the flow tube measurement data at the inlet end of the first air flow tube is stable, the first flow value of the flow tube is read, and the second flow of the flow meter in the inner exhaust pipe and the pressure value of the pressure measuring probe in the outer exhaust pipe are read respectively; According to the pressure value of the pressure measuring probe, a third flow rate in the outer exhaust pipe is obtained by analyzing the flow rate formula; If the first flow value data is the sum of the second flow and the third flow, the first flow data is output as the flow test value of the dual-duct compression component. Otherwise, the airtight performance of the flow measurement system of the dual-duct compression component is checked until the first flow value data is the sum of the second flow and the third flow, and then the first flow data is output as the flow test value of the dual-duct compression component.

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