Measuring device, measuring system and measuring method for engine transition state flow

Abstract

The invention provides a measuring device, a measuring system and a measuring method for engine transition state flow. The measuring device for the engine transition state flow is used for measuring the transition state flow of airflow in an engine casing and comprises a mounting base, an air inlet supporting rod, a total pressure measuring pipe and a static pressure measuring pipe. Wherein the air inlet supporting rod is arranged on the mounting seat, and the mounting seat is used for being assembled on the casing. A total pressure measuring channel and a static pressure measuring channel are formed in the air inlet supporting rod. The air inlet supporting rod is provided with at least one total pressure measuring hole communicated with the total pressure measuring channel and the outside and at least one static pressure measuring hole communicated with the static pressure measuring channel and the outside. The total pressure measuring channel is communicated with the total pressure measuring pipe, and the static pressure measuring channel is communicated with the static pressure measuring channel. The total pressure measuring pipe and the static pressure measuring pipe are used for being connected with a differential pressure sensor so as to obtain the differential pressure between the total pressure and the static pressure. The measuring device can measure the transition state flow change timely and accurately.

Description

Technical Field

[0001] This invention relates to the technical field of aero-engine testing, and in particular to a measuring device, measuring system, and measuring method for measuring engine transient flow. Background Technology

[0002] The parameters of the transition state test of an aero-engine, especially the internal flow parameters, directly reflect the performance of the engine. Currently, the flow measurement method mostly uses the inlet section flow tube, which is suitable for steady-state measurement processes.

[0003] However, because the flow tube is installed far from each cross-section of the internal structure, it cannot reflect the flow changes during the transition test at each cross-section in a timely manner, affecting the engine performance assessment and evaluation. For flow measurement at the internal cross-section, if a typical Pitot tube-type sensing element for flow testing is used, a larger interface is required, which will affect the flow channel profile and thus lead to a larger deviation in the flow measurement value. Summary of the Invention

[0004] The purpose of this invention is to provide a measuring device, measuring system and measuring method for measuring engine transition flow, which can measure the change of transition flow in a timely and accurate manner.

[0005] One aspect of the present invention provides a device for measuring the transitional flow rate of an engine, used to measure the transitional flow rate of airflow within an engine casing; the measuring device includes a mounting base, an intake strut, a total pressure measuring tube, and a static pressure measuring tube; wherein, the intake strut is disposed on the mounting base, and the mounting base is used to assemble into the engine casing; the intake strut has an internal total pressure measuring channel and a static pressure measuring channel; the intake strut has at least one total pressure measuring hole connecting the total pressure measuring channel and the outside, and at least one static pressure measuring hole connecting the static pressure measuring channel and the outside; the total pressure measuring channel is connected to the total pressure measuring tube, and the static pressure measuring channel is connected to the static pressure measuring tube; both the total pressure measuring tube and the static pressure measuring tube are used to connect to a differential pressure sensor to obtain the pressure difference between the total pressure and the static pressure.

[0006] In one embodiment, the total pressure measurement channel and the static pressure measurement channel extend along the axial direction of the intake strut; the total pressure measuring tube and the total pressure measurement channel are arranged coaxially; the static pressure measuring tube and the static pressure measurement channel are arranged coaxially.

[0007] In one embodiment, there are multiple total pressure measuring holes, which are spaced apart along the total pressure measuring channel; and / or there are multiple static pressure measuring holes, which are spaced apart along the static pressure measuring channel.

[0008] In one embodiment, the total length of the total pressure measurement channel and the total pressure measuring tube is equal to the total length of the static pressure measurement channel and the static pressure measuring tube.

[0009] In one embodiment, the intake strut includes a first side and a second side; the static pressure measuring hole includes a first static pressure measuring hole and a second static pressure measuring hole; the first static pressure measuring hole extends from the static pressure measuring channel to the first side of the intake strut, and the second static pressure measuring hole extends from the static pressure measuring channel to the second side of the intake strut.

[0010] In one embodiment, the included angle between the first side and the second side is an acute angle.

[0011] In one embodiment, the mounting base includes a mounting surface opposite to the intake strut, the mounting surface being radially inclined relative to the intake strut.

[0012] In one embodiment, the measuring device further includes a rectification structure; wherein the rectification structure includes a shroud and an air pipe, the shroud having a cavity, at least a portion of the air pipe being located within the cavity; the shroud having a through air inlet and an exhaust outlet; the shroud being disposed on the air inlet support rod, the total pressure measuring hole being connected to the air pipe, and the air pipe being connected to the outside through the air inlet and the exhaust outlet.

[0013] In one embodiment, the air pipe is inclinedly disposed in the total pressure measurement channel; and / or the first side and the second side are connected to form a first end, the total pressure measurement channel being closer to the first end relative to the static pressure measurement channel; the first end has a mounting portion communicating with the total pressure measurement hole, and at least a portion of the fairing is mounted in the mounting portion.

[0014] Another aspect of the present invention provides a measurement system for engine transient flow, comprising: an engine transient flow measuring device as described in any of the above embodiments; a differential pressure sensor connected to the total pressure measuring tube and the static pressure measuring tube of the measuring device, the differential pressure sensor being used to measure the pressure difference between the total pressure obtained from the total pressure measuring tube and the static pressure obtained from the static pressure measuring tube; and a data acquisition device connected to the differential pressure sensor.

[0015] Another aspect of the present invention provides a method for measuring the transition flow rate of an engine, applied to an engine transition flow rate measurement system as described in the above embodiments; the measurement method includes: calibrating the measurement system to obtain a correspondence between differential pressure and flow rate; extending the intake strut of the measuring device into the casing of the engine to be measured, and assembling the measuring device in the casing; obtaining the transition flow rate of the engine to be measured based on the correspondence and the differential pressure read by the differential pressure sensor.

[0016] The engine transient flow measurement device of this invention outputs one total pressure signal and one static pressure signal in the form of a total pressure measuring tube and a static pressure measuring tube. Then, a differential pressure sensor is used to convert the total pressure signal and the static pressure at the static pressure measuring point into a differential pressure signal. This invention can reduce interface size, has less impact on the flow channel profile, and is more suitable for internal measurement. Compared with the traditional pressure ratio method using multiple pressure sensors, the differential pressure method of this invention avoids the interference effect caused by measuring the static pressure of the flow channel, reduces measurement errors, and lowers the cost of connecting a transient pressure sensor to each measuring point. This invention is less sensitive to random errors during the measurement process, and the measurement results are more reliable, enabling timely and accurate measurement of transient flow changes. Attached Figure Description

[0017] The above and other features, properties and advantages of the present invention will become more apparent from the following description taken in conjunction with the accompanying drawings and embodiments, wherein:

[0018] Figure 1 This is a schematic diagram of an embodiment of an engine transition flow measurement device according to the present invention;

[0019] Figure 2 yes Figure 1 A schematic diagram of the total pressure measuring port and the cross-section of the rectifier structure of the measuring device shown.

[0020] Figure 3 yes Figure 1 A schematic cross-sectional view of the static pressure measuring orifice of the measuring device shown;

[0021] Figure 4 This is a schematic diagram of an embodiment of an engine transient flow measurement system according to the present invention;

[0022] Figure 5 This is a schematic flowchart of an embodiment of the engine transient flow measurement method according to the present invention;

[0023] Figure 6 yes Figure 5 The calibration process diagram in step S100 of the measurement method shown is illustrated. Detailed Implementation

[0024] Reference will now be made in detail to embodiments of the invention, one or more examples of which are illustrated in the accompanying drawings. Each example is provided to explain the invention and not to limit it. In fact, it will be apparent to those skilled in the art that various modifications and variations may be made to the invention without departing from the scope or spirit thereof. For example, a feature shown or described as part of one embodiment may be used with another embodiment to produce yet another embodiment. Therefore, the invention is intended to cover these modifications and variations that fall within the scope of the appended claims and their equivalents.

[0025] The term "axial" refers to the central axis of the intake strut or a direction parallel to the central axis of the intake strut; the term "radial" refers to a direction perpendicular to the "axial" direction; and the term "circumferential" refers to a direction about the "axial" direction. As used herein, the terms "first," "second," and "third" may be used interchangeably to distinguish one component from another and are not intended to indicate the location or importance of individual components. The terms "upstream" and "downstream" refer to the relative directions of airflow within a fluid path. For example, "upstream" refers to the direction from which airflow originates, and "downstream" refers to the direction towards which airflow originates.

[0026] Figure 1 An embodiment of the engine transient flow measurement device of the present invention is shown. The engine transient flow measurement device of the present invention is used during the transient test of an aero-engine to measure the transient mass flow of the airflow within the engine casing. An aero-engine undergoes different operating states throughout its entire operating envelope, including stable and unstable operating states. Unstable operating states are also known as transient states. Typical transient states include starting, acceleration, and deceleration processes.

[0027] Typically, the performance and parameter matching of major components of an aero-engine / gas turbine are based on the stable state of each component. However, in the transition state, because the engine's operating parameters change rapidly over time, the actual performance of each component deviates significantly from the stable state. The differences in the changes of some components may even exceed their design expectations. This deviation between engine performance and structural state in the transition state not only affects engine performance but also poses a threat to engine safety.

[0028] The measuring device of the present invention is not limited to use in the transition state and surge test projects of different internal cross sections of the engine, but can also be used in other conventional test projects.

[0029] like Figure 1As shown, the measuring device includes a mounting base 100, an intake strut 200, a total pressure measuring tube 300, and a static pressure measuring tube 400. The intake strut 200 is mounted on the mounting base 100, which is used to assemble into the engine casing. A connector 600 is mounted on the mounting base 100 and is used to fix the mounting base 100 to the engine casing. The connector 600 can be a flange structure, which can be bolted to the engine casing interface. The side of the connector 600 closest to the mounting base 100 (i.e.,...) Figure 1 A flat gasket 700 is provided on the right side of the connecting member 600. When the measuring device is assembled into the housing, the flat gasket 700 abuts against the housing to install a seal and prevent air leakage, thereby reducing measurement errors. The air intake support rod 200 and the mounting base 100 are connected by argon arc welding.

[0030] The intake strut 200 has a total pressure measurement channel 201 and a static pressure measurement channel 202 inside. The total pressure measurement channel 201 and the static pressure measurement channel 202 extend along the axial direction of the intake strut 200. Optionally, the total pressure measurement channel 201 and the static pressure measurement channel 202 are deep holes with a diameter of 1.1 mm.

[0031] The intake strut 200 has at least one total pressure measuring hole 201a connecting the total pressure measuring channel 201 to the outside and at least one static pressure measuring hole 202a connecting the static pressure measuring channel 202 to the outside. The total pressure measuring hole 201a allows airflow to enter the total pressure measuring channel 201, and the static pressure measuring hole 202a allows airflow to enter the static pressure measuring channel 202.

[0032] The total pressure measurement channel 201 is connected to the total pressure measuring tube 300, and the static pressure measurement channel 202 is connected to the static pressure measuring channel 202. The total pressure measuring tube 300 and the total pressure measurement channel 201 are arranged on the same axis, and the static pressure measuring tube 400 and the static pressure measurement channel 202 are also arranged on the same axis. That is to say, the total pressure measuring tube 300 and the total pressure measurement channel 201 are located on the same straight line, and the static pressure measuring tube 400 and the static pressure measurement channel 202 are located on the same straight line.

[0033] When the measuring device of the present invention is assembled in the casing, the intake support rod 200 extends into the flow channel of the casing. The total pressure measuring channel 201 is located upstream of the total pressure measuring tube 300, and the static pressure measuring channel 202 is located upstream of the static pressure measuring tube 400. The airflow can sequentially enter the total pressure measuring hole 201a, the total pressure measuring channel 201, and the total pressure measuring tube 300, finally reaching the total pressure measuring point located in the total pressure measuring tube 300. Similarly, the airflow can sequentially enter the static pressure measuring hole 202a, the static pressure measuring channel 202, and the static pressure measuring tube 400, finally reaching the static pressure measuring point located in the static pressure measuring tube 400. The total pressure measuring point of the total pressure measuring tube 300 and the static pressure measuring point of the static pressure measuring tube 400 are both used to connect with a differential pressure sensor to obtain the pressure difference between the total pressure and the static pressure of the flow channel.

[0034] The engine transient flow measurement device of the present invention outputs one total pressure signal and one static pressure signal in the form of a total pressure measuring tube 300 and a static pressure measuring tube 400, thereby achieving the averaging of the pressure parameters of the internal cross section. Furthermore, a differential pressure sensor is used to convert the total pressure signal and the static pressure at the static pressure measuring point into a differential pressure signal. This invention can reduce interface size, has less impact on the flow channel profile, and is more suitable for internal measurement.

[0035] Compared with the traditional pressure ratio method that uses multiple pressure sensors, the differential pressure method of this invention can avoid the interference caused by the static pressure of the measuring channel, reduce measurement errors, and reduce the cost of connecting a transient pressure sensor to each measuring point.

[0036] This invention is less sensitive to random errors in the measurement process, and the measurement results are more reliable. It can measure the transient flow rate changes in a timely and accurate manner.

[0037] In one embodiment, the total length of the total pressure measurement channel 201 and the total pressure measuring tube 300 is equal to the total length of the static pressure measurement channel 202 and the static pressure measuring tube 400. This ensures the consistency of the phase response of the total pressure and static pressure to the transition pressure, allowing direct connection to a differential pressure sensor for subtraction to obtain the differential pressure value, thus achieving rapid and accurate measurement. Optionally, the lengths of the total pressure measuring tube 300 and the static pressure measuring tube 400 at the tail end are both controlled to 1m ± 0.2m, and their inner diameters are consistent with the diameters of the total pressure measurement channel 201 and the static pressure measurement channel 202, respectively. This makes the measured values ​​more representative and reduces measurement errors.

[0038] Considering the actual working conditions within the flow channel, the airflow has a certain deflection angle. The measuring device also includes a rectifying structure 500, which can reduce the influence of the deflection angle on the measurement results. The rectifying structure 500 includes a shroud 510 and an air pipe 520. The shroud 510 has a cavity 511, and at least a portion of the air pipe 520 is located within the cavity 511. Optionally, the air pipe 520 is fixed to the intake support rod 200 by laser welding for total pressure measurement and airflow guidance. The shroud 510 has a through-hole slit 512 and an exhaust slit 513. The shroud 510 is mounted on the intake support rod 200, and the total pressure measurement hole 201a is connected to the air pipe 520. The air pipe 520 is connected to the outside through the slit 512 and the exhaust slit 513.

[0039] like Figure 2 As shown in the total pressure section, based on the above embodiment, the air pipe 520 is inclinedly arranged in the total pressure measurement channel 201, which can reduce the impact of the airflow pitch angle in the actual working conditions of the corresponding section. The inclination angle of the air pipe 520 is determined according to the actual situation, and the present invention does not impose any limitations.

[0040] The first side 210 and the second side 220 are connected to form a first end 240, and the total pressure measurement channel 201 is closer to the first end 240 than the static pressure measurement channel 202. The first end 240 has a mounting portion 240a that communicates with the total pressure measurement port 201a, and at least part of the fairing 510 is installed in the mounting portion 240a. It is understood that the number of total pressure measurement ports 201a is the same as the number of rectifier structures 500.

[0041] The total pressure measurement points within the flow channel are distributed in annular shapes. Multiple total pressure measurement holes 201a can be selected, and these holes are spaced apart along the total pressure measurement channel 201. As the spacing between the annular surfaces of the flow channel increases, the spacing between adjacent total pressure measurement holes 201a (i.e., the rectifying structure 500) also increases. Figure 1 The spacing between adjacent rectifier structures 500 closer to the right in the middle and the middle is larger.

[0042] The number of total pressure measuring holes 201a can be set according to the actual engine cross-section requirements, so as to... Figure 1 For example, the quantity can be selected as 5.

[0043] Multiple static pressure measuring holes 202a can also be selected, and multiple static pressure measuring holes 202a are arranged at intervals along the static pressure measuring channel 202. The static pressure measuring holes 202a are located near the theoretical static pressure position on the intake support rod 200, which can be obtained through fluid simulation calculations.

[0044] The present invention does not restrict the positional relationship between the total pressure measuring hole 201a and the static pressure measuring hole 202a. Preferably, in the radial direction of the intake strut 200, the static pressure measuring hole 202a is located between two adjacent total pressure measuring holes 201a. According to actual measurement results, this can improve the accuracy of the measurement results.

[0045] refer to Figure 1 In one embodiment, the mounting base 100 includes a mounting surface 110 opposite to the intake strut 200. The mounting surface 110 is radially inclined relative to the intake strut 200 to accommodate the gradually increasing thickness of the casing, so as to ensure that the intake strut 200 is completely located within the flow channel.

[0046] like Figure 2 and Figure 3 As shown, the intake strut 200 is triangular, and the connection points of the first side 210, the second side 220, and the third side 230 are all chamfered.

[0047] like Figure 3The static pressure cross-section shown includes a first static pressure measuring hole 202a-1 and a second static pressure measuring hole 202a-2. The first static pressure measuring hole 202a-1 extends from the static pressure measuring channel 202 to the first side surface 210 of the intake strut 200, and the second static pressure measuring hole 202a-2 extends from the static pressure measuring channel 202 to the second side surface 220 of the intake strut 200. Figure 3 The static pressure section shown has openings on both the left and right sides that are interconnected, which can reduce the influence of the static pressure measuring point on the circumferential deflection angle of the airflow and obtain a measurement value close to the theoretical static pressure of the flow channel.

[0048] The included angle between the first side surface 210 and the second side surface 220 is an acute angle. Experimental verification shows that this included angle can be selected from 20° to 40°, preferably 30°. In this case, it is easier to obtain the static pressure value of the flow channel in the first side surface 210 and / or the opening.

[0049] like Figure 4 As shown, one embodiment of the engine transient flow measurement system of the present invention includes a measuring device, a differential pressure sensor, and a data acquisition device. The differential pressure sensor is connected to the total pressure measuring tube 300 and the static pressure measuring tube 400 of the measuring device. The differential pressure sensor measures the pressure difference between the total pressure obtained from the total pressure measuring tube 300 and the static pressure obtained from the static pressure measuring tube 400. In other words, the total static pressure sensing part transmits one signal each of the total pressure and static pressure of the internal cross-section to the differential pressure sensor, outputting the differential pressure physical quantity. This reduces the cost associated with connecting a transient pressure sensor to each measuring point in the traditional pressure ratio method. The data acquisition device is connected to the differential pressure sensor for signal acquisition and display.

[0050] like Figure 5 As shown, the engine transient flow measurement method of the present invention is applied to an embodiment of the engine transient flow measurement system described above. The measurement method of the present invention includes steps S100 to S300:

[0051] In step S100, the measurement system is calibrated to obtain the correspondence between pressure difference and flow rate.

[0052] In step S200, the intake support rod 200 of the measuring device is inserted into the casing of the engine to be measured, and the measuring device is assembled into the casing.

[0053] In step S300, the transient flow rate of the engine to be measured is obtained by combining the corresponding relationship with the differential pressure reading obtained by the differential pressure sensor.

[0054] Traditional pressure ratio methods require separate measurements of total pressure and static pressure, followed by conversion to airflow rate using Mach number. This invention, however, employs a differential pressure method, which is less sensitive to random errors during the measurement process, resulting in more reliable measurement results.

[0055] like Figure 6 As shown, in step S100, before the transient test, the measurement system is calibrated using a steady-state step. Calibration can be derived from a steady-state flow meter or an established engine speed-flow relationship model, thereby establishing the correspondence between the output pressure difference and flow rate of the test system. During the transient test, this relationship can be used to convert the transient pressure difference value into a transient flow rate value, thus achieving the measurement of the transient flow rate. Compared to formula calculation, calibration on the bench allows for obtaining more accurate flow rate values ​​under different test environments.

[0056] While the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the invention. Any variations and modifications can be made by those skilled in the art without departing from the spirit and scope of the invention. Therefore, any modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention, without departing from the scope of the invention, fall within the protection scope defined by the claims of the present invention.

Claims

1. A device for measuring the transitional flow rate of an engine, used to measure the transitional flow rate of airflow within an engine casing; Its features are, The measuring device includes a mounting base, an air intake support rod, a total pressure measuring tube, and a static pressure measuring tube; wherein... The air intake strut is disposed on the mounting base, and the mounting base is used to assemble into the casing; The intake support rod is equipped with a total pressure measurement channel and a static pressure measurement channel inside. The intake support rod has at least one total pressure measuring hole connecting the total pressure measuring channel and the outside, and at least one static pressure measuring hole connecting the static pressure measuring channel and the outside. The total pressure measurement channel and the total pressure measuring tube are connected, and the static pressure measurement channel and the static pressure measurement channel are connected; Both the total pressure measuring tube and the static pressure measuring tube are used to connect to the differential pressure sensor to obtain the pressure difference between the total pressure and the static pressure.

2. The measuring device as described in claim 1, characterized in that, The total pressure measurement channel and the static pressure measurement channel extend along the axial direction of the intake strut; The total pressure measuring tube and the total pressure measuring channel are arranged along the same axis; The static pressure measuring tube and the static pressure measuring channel are arranged along the same axis.

3. The measuring device as described in claim 2, characterized in that, The total pressure measuring holes are multiple, and the multiple total pressure measuring holes are spaced apart along the total pressure measuring channel; and / or There are multiple static pressure measuring holes, which are spaced apart along the static pressure measuring channel.

4. The measuring device as described in claim 2, characterized in that, The total length of the total pressure measurement channel and the total pressure measuring tube is equal to the total length of the static pressure measurement channel and the static pressure measuring tube.

5. The measuring device as described in any one of claims 1 to 4, characterized in that, The intake strut includes a first side and a second side; The static pressure measuring hole includes a first static pressure measuring hole and a second static pressure measuring hole; The first static pressure measuring hole extends from the static pressure measuring channel to the first side of the intake support rod, and the second static pressure measuring hole extends from the static pressure measuring channel to the second side of the intake support rod.

6. The measuring device as described in claim 5, characterized in that, The angle between the first side and the second side is an acute angle.

7. The measuring device according to any one of claims 1 to 4, characterized in that, The mounting base includes a mounting surface opposite to the air intake strut, the mounting surface being radially inclined relative to the air intake strut.

8. The measuring device as described in claim 5, characterized in that, The measuring device further includes a rectifier structure; wherein... The rectification structure includes a shroud and an air pipe, the shroud being provided with a cavity, and at least a portion of the air pipe being located within the cavity; The fairing has through-holes for air intake and exhaust. The fairing is mounted on the air intake support rod, the total pressure measuring hole is connected to the air pipe, and the air pipe is connected to the outside through the air intake hole and the exhaust hole.

9. The measuring device as described in claim 8, characterized in that, The air pipe is inclinedly positioned within the total pressure measurement channel; and / or The first side and the second side are connected to form a first end, and the total pressure measurement channel is closer to the first end relative to the static pressure measurement channel; The first end has a mounting portion that communicates with the total pressure measuring hole, and at least part of the fairing is installed in the mounting portion.

10. A system for measuring the transient flow rate of an engine, characterized in that, include: The measuring device for engine transition flow rate as described in any one of claims 1 to 9; A differential pressure sensor is connected to the total pressure measuring tube and the static pressure measuring tube of the measuring device. The differential pressure sensor is used to measure the pressure difference between the total pressure obtained from the total pressure measuring tube and the static pressure obtained from the static pressure measuring tube. A data acquisition device is connected to the differential pressure sensor.

11. A method for measuring the transient flow rate of an engine, characterized in that, Applied to the engine transient flow measurement system as described in claim 10; The measurement method includes: The measurement system was calibrated to obtain the correspondence between pressure difference and flow rate; The intake strut of the measuring device is inserted into the housing of the engine to be measured, and the measuring device is assembled into the housing. Based on the aforementioned correspondence and the differential pressure read from the differential pressure sensor, the transient flow rate of the engine to be measured is obtained.

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