A multi-point dynamic full-parameter measurement device for subsonic two-dimensional flow field

Abstract

The present invention belongs to the technical field of flow field testing, and discloses a multi-point dynamic full-parameter measurement device for subsonic two-dimensional flow field, including a head, a transition section, and a support rod. The head and the support rod are cylindrical, the total pressure hole and two pressure sensing holes on the windward side of the head form a three-hole structure, and the leeward side opens a total temperature hole. The total temperature hole and the total pressure hole are arranged in reverse and the center line is collinear. Multiple three-hole structures and total temperature holes are distributed along the axial direction and the center line directions of each total pressure hole are different. The temperature sensor is located in the total temperature hole and the front end is flush with the cylindrical surface of the head. The pressure sensor is packaged in the total pressure hole and the pressure sensing hole, and the temperature and pressure sensor cables are led out through the internal channel of the device. The present invention can simultaneously realize multi-point dynamic measurement of full parameters such as total temperature, total pressure, static temperature, static pressure, Mach number, deflection angle, speed, density, etc. The total temperature and total pressure measurement have high accuracy, and are used for multi-point full-parameter dynamic measurement of aircraft engine inlet ducts and multi-point full-parameter dynamic measurement of impeller machinery inlet, outlet and blade row along the blade height direction.

Description

Technical Field

[0001] The present invention relates to the field of flow field testing technology, and in particular to a multi-point dynamic full-parameter measurement device for a subsonic two-dimensional flow field, which is used for full-parameter dynamic measurement of multiple points along one direction of an aircraft engine inlet and full-parameter dynamic measurement of multiple points along the blade height direction between an impeller machine inlet, outlet and blade rows. Background Art

[0002] The performance tests of compressors, turbines, pumps, blowers, and fans need to measure the distribution of the flow field parameters of the blade inlet, outlet, and interstage along the blade height direction in the flow channel. The existing probe technology can achieve this in the following ways:

[0003] When using a single-point temperature and pressure combination probe, the probe displacement mechanism is required to drive the probe to measure at different blade heights. The test measurement time is long and the test cost is high. In addition, the multi-point measurement results of this method are not obtained at the same time. If dynamic measurement of an unsteady flow field is performed, the results measured at each point cannot be compared, and only steady-state measurement can be achieved.

[0004] Since the existing multi-point pressure probe can generally only realize multi-point total pressure measurement, but cannot realize simultaneous measurement of multiple parameters, a single-point three-hole pressure probe and a multi-point total temperature probe can be used to measure the distribution of parameters at each point. When measuring pressure, the probe displacement mechanism needs to be used to drive the probe to measure separately at different leaf height positions. The test measurement time is long, the test cost is high, and the measurement results cannot be obtained at the same time, which is only applicable to steady-state measurement. In addition, this measurement requires that the measuring points of the pressure probe and the total temperature probe are consistent. However, on the one hand, due to the existence of installation errors, it is difficult to ensure that the measuring points of the probes are consistent; on the other hand, even if the existence of installation errors is not considered, due to the complexity and non-steadiness of the flow in the flow field, the flow conditions at each point of the two measurements are completely different, so it is not suitable for dynamic measurement; in addition, the temperature and pressure are measured separately, and the installation process is cumbersome, which also increases the time cost of the test operation and the difficulty of the test.

[0005] The internal profile of the total pressure hole of the existing dynamic pressure probe is generally a straight transition, which will cause a certain total pressure loss and lead to inaccurate measurement results. In addition, the straight transition will cause flow separation, and the fluctuations caused by flow separation will also interfere with the total pressure measurement results.

[0006] The existing probes that can realize temperature parameter measurement include total temperature probe and temperature and pressure combined probe. According to the existing total temperature probe design concept, the key to the temperature probe accurately measuring the total temperature of the airflow is whether the airflow can be absolutely stagnant at the temperature measurement point. Therefore, most of the existing temperature probes are designed according to the requirement that the temperature sensor is facing the mainstream. The temperature probe head adopts a stagnation cover structure to collect the incoming flow, and the temperature sensor is placed in the stagnation cover. Its disadvantages are: first, the temperature sensor is directly washed by the fluid and is easily affected by oil droplets, dust, etc. mixed in the airflow, and is easy to be damaged; second, the strength of the sensor is usually improved by increasing the size of the temperature sensor, and the size of the stagnation cover is added, so the probe size is large, which will make its spatial resolution poor; third, the airflow insensitive angle is small, when the deflection angle of the incoming flow to be measured is large, the airflow cannot be fully stagnant; fourth, the heat exchange on the temperature sensor surface is insufficient, and the total temperature measurement error is large; at the same time, a single total temperature probe cannot realize the measurement of all dynamic parameters of the subsonic flow field.

[0007] There are also methods that use a single temperature-pressure combination probe to simultaneously measure the temperature and pressure of a single point in the flow field. The temperature sensors of the existing temperature-pressure combination probes are all facing the mainstream, and they have the shortcomings of the above-mentioned temperature probes. Moreover, the temperature and pressure measurement points do not measure the parameters of the same streamline, resulting in poor spatial resolution and measurement errors. Therefore, the above-mentioned problems exist in temperature measurement, and it is difficult to meet the needs of accurate measurement of all two-dimensional dynamic parameters of subsonic flow fields. Therefore, there is an urgent need for a multi-point dynamic full-parameter measurement device for subsonic two-dimensional flow fields, which can be used for dynamic and accurate measurement of all parameters such as total temperature, total pressure, static temperature, static pressure, Mach number, deflection angle, speed, density, etc. at multiple points along the radial direction of the aircraft engine inlet and at multiple points along the blade height direction between the impeller mechanical inlet, outlet and blade rows.

[0008] Under external interference, the output of the pressure sensor will undergo unwanted changes that are unrelated to the input, i.e. drift. Drift includes zero drift and sensitivity drift. Zero drift or sensitivity drift can be divided into time drift and temperature drift. Time drift refers to the slow change of zero point or sensitivity over time under specified conditions, and temperature drift refers to the drift of zero point or sensitivity caused by changes in ambient temperature. Temperature drift is one of the main causes of pressure sensor measurement errors. The zero output voltage of different pressure sensors changes with temperature, and their change trends and amplitudes vary. Therefore, temperature correction for the zero drift of a specific pressure sensor is a necessary condition to ensure the accuracy of pressure measurement. However, the existing multi-point measurement probe can only measure the total pressure but cannot measure the total temperature and static temperature parameters. Therefore, it is impossible to correct the pressure sensor in time and the accuracy of the pressure measurement results cannot be guaranteed.

[0009] The boundary layer of the inner wall of the casing of the aircraft engine inlet, compressor, fan, etc. is affected by the rotation of the rotor, the staggered arrangement of the moving and static blade rows, and the interaction between the blade tip gap leakage flow and the boundary layer. The flow inside is very complex, and the existing probes for measuring the parameters in the boundary layer are all steady-state probes, which cannot realize the dynamic measurement of all parameters in the boundary layer. At the same time, due to the thin thickness of the boundary layer, the boundary layer pressure probe, temperature probe, and hot wire anemometer are often used separately to measure the total pressure, temperature and velocity parameters in the boundary layer, that is, a single probe is used separately to measure a single parameter. On the one hand, this measurement method will cause greater interference to the thin boundary layer flow field, and on the other hand, it increases the complexity of the test and the cost of the test. The most important thing is that the flow parameters measured by different probes cannot be guaranteed to come from the same streamline, so when the combined calculation of parameters such as velocity will bring additional errors, thereby reducing the accuracy of the test.

[0010] The existing multi-point full-parameter dynamic measurement technology has the following shortcomings: 1. When using a single-point measurement probe for multi-point measurement, the existing single-point measurement probe, whether it is a pressure probe or a temperature-pressure combination probe, needs to use a probe displacement mechanism to drive the probe to measure separately at different blade height positions, which results in a long test measurement time, high test cost, and cannot be used for dynamic measurement of complex flow fields; 2. The existing multi-point measurement probe can only achieve steady-state measurement of total pressure, and cannot achieve multi-point measurement of full parameters such as total temperature, total pressure, static temperature, static pressure, Mach number, deflection angle, speed, density, etc., nor can it achieve dynamic measurement; 3. The internal profile of the total pressure hole of the existing dynamic pressure probe is generally a straight transition, which causes a certain total pressure loss, resulting in inaccurate dynamic measurement results; in addition, the straight transition will cause flow separation, and the fluctuations caused by flow separation will also interfere with the dynamic total pressure measurement results; 4. The existing total temperature and temperature-pressure combination probes have the problem of temperature sensor being positive in temperature measurement. The mainstream is directly washed by the fluid, and is easily affected by oil droplets, dust, etc. mixed in the airflow. It is easy to be damaged, the probe size is large, the spatial resolution is poor, and the airflow insensitive angle is small. When the deflection angle of the incoming flow to be measured is large, the airflow cannot be fully stagnant, the heat exchange on the temperature sensor surface is insufficient, and the total temperature measurement error is large. At the same time, a single total temperature probe cannot realize the measurement of all dynamic parameters of the subsonic flow field; 5. The existing multi-point measurement probe can only measure the total pressure but cannot measure the total temperature and static temperature parameters. Therefore, the pressure sensor cannot be corrected in time, and the accuracy of the pressure measurement results cannot be guaranteed. 6. The existing probes for measuring the parameters in the boundary layer are all steady-state probes, which cannot realize the dynamic measurement of all parameters in the boundary layer. Using multiple probes to measure each parameter separately will cause greater interference to the thin boundary layer flow field, increasing the complexity of the test and the cost of the test. At the same time, the flow parameters measured by different probes cannot be guaranteed to come from the same streamline, which reduces the accuracy of the test. Summary of the invention

[0011] In view of the above-mentioned deficiencies in the prior art, the present invention provides a multi-point dynamic full-parameter measurement device for subsonic two-dimensional flow fields, aiming to solve the following problems: the single-point measurement probes currently existing in the field of multi-point dynamic full-parameter measurement of subsonic two-dimensional flow fields have a long measurement time and high test cost when performing multi-point measurement, and cannot be used for dynamic measurement of complex flow fields; the multi-point measurement probe can only realize steady-state measurement of total pressure, and cannot realize the correction of zero-point temperature drift of the pressure sensor, nor can it realize multi-point dynamic measurement of full parameters such as total temperature, total pressure, static temperature, static pressure, Mach number, deflection angle, speed, density, etc.; the straight transition of the internal profile of the total pressure hole of the dynamic pressure probe causes a certain total pressure loss, resulting in inaccurate measurement results; the existing total temperature and temperature-pressure combination probes have a large number of problems in temperature measurement. In terms of temperature measurement, there are problems such as the temperature sensor is directly flushed by the mainstream fluid and is easily damaged by oil droplets, dust, etc. in the airflow; the probe size is large, resulting in poor spatial resolution; the airflow insensitivity angle is small, resulting in the inability to fully stagnate the airflow; the insufficient heat exchange on the temperature sensor surface causes a large total temperature measurement error; a single total temperature probe cannot achieve dynamic full-parameter measurement of the subsonic flow field; the existing probes for measuring parameters in the boundary layer are all steady-state probes, which cannot achieve dynamic measurement of all parameters in the boundary layer. Using multiple probes to measure each parameter separately will cause greater interference to the thin boundary layer flow field, increasing the complexity of the test and the cost of the test. At the same time, the flow parameters measured by different probes cannot be guaranteed to come from the same streamline, reducing the accuracy of the test.

[0012] In the present invention, the total temperature holes are distributed at 180° to the total pressure holes and their center lines are collinear, abandoning the traditional total temperature probe design concept. The design is not based on the method of placing the temperature sensor directly opposite the mainstream and using a stagnation hood to stop the airflow to achieve total temperature measurement. Instead, based on the applicant's many years of research, a layout and structural design in which the temperature sensor is placed on the leeward side of the head is creatively proposed, and the temperature sensor is directly opposite the pressure sensing hole, which effectively reduces the scouring of the temperature sensor by the airflow and the influence of oil droplets, dust, etc. mixed in the airflow on the temperature sensor, making it possible to use a temperature sensor of extremely small size and improving the service life of the temperature sensor; effectively reducing the size of the head and improving the spatial resolution of the probe; strengthening the convective heat exchange between the airflow and the temperature sensor, and the temperature recovery coefficient is high and stable within a larger deflection angle range; at the same time, the parameters measured by the temperature sensor and the pressure sensor are the parameters of the same streamline, and the zero drift of the pressure sensor used can be temperature corrected, thereby ensuring the accuracy of the pressure measurement.

[0013] The head of the present invention is provided with multi-point total temperature holes and a "three-hole structure" for pressure measurement. Both the temperature sensor and the pressure sensor are dynamic sensors. The device alone can be used to realize the simultaneous dynamic measurement of multi-point total temperature, total pressure, static temperature, static pressure, Mach number, deflection angle, speed, density and other full parameters. There is no need to use a probe displacement mechanism to drive the probe to measure separately at different blade height positions, thus saving test time. The head size is very small and the top and bottom measurement holes are close to the end, so it can be used to measure boundary layer parameters.

[0014] The total pressure hole of the present invention adopts a smooth transition of a micro-loss convergent surface. Compared with the straight transition section of the existing dynamic total pressure probe, it can reduce total pressure loss and flow separation when converging within a wider deflection angle range, reduce pressure fluctuations caused by the pressure sensing hole structure, and improve the accuracy of total pressure measurement. The total temperature hole adopts a truncated cone-shaped hole, which can have a high and stable temperature recovery coefficient within a larger deflection angle range, which is beneficial to enhancing the convective heat exchange between the airflow and the temperature sensor. The front end of the temperature sensor of the present invention is flush with the cylindrical surface of the head, that is, the measuring point of the temperature sensor is exactly located on the cylindrical surface of the head, which can make full use of the flow characteristics of the head to achieve accurate temperature measurement.

[0015] In order to solve the above technical problems, the present invention provides a multi-point dynamic full-parameter measurement device for a subsonic two-dimensional flow field, characterized in that it comprises a head (1), a transition section (2), and a support rod (3), the head (1) and the support rod (3) are both cylindrical, a total pressure hole (7) is opened on the windward surface of the head (1), the center line of the total pressure hole (7) is perpendicular to the center line of the head (1), there is a pressure sensing hole (8) on each side of the total pressure hole (7), the total pressure hole (7) and the pressure sensing holes (8) on both sides thereof are at an angle of 15° to 16°, and The center lines of the total pressure hole (7) and the pressure sensing holes (8) on both sides thereof are on the same plane, forming a three-hole structure. A total temperature hole (9) is opened on the leeward side of the head (1). The total temperature hole (9) and the total pressure hole (7) are 180 degrees apart and their center lines are collinear. The temperature sensor (6) is located in the total temperature hole. A pressure sensor (11) is respectively encapsulated in the total pressure hole (7) and the pressure sensing hole (8). A sensor cable lead-out channel (12) is opened in the head of the device. The pressure sensor cable (4) and the temperature sensor cable (5) are led out from the tail of the device through the channel.

[0016] Furthermore, at least five of the above-mentioned three-hole structures and at least five total temperature holes (9) are distributed at different axial positions along the head (1), and the distribution pattern may be uniform distribution, with the axial distance between the center lines of two adjacent holes being 0.3 to 0.9 mm; or it may present a distribution pattern of sparse distribution in the middle and dense distribution on both sides, with the axial distance between the center lines of the first total pressure hole (7) and the second total pressure hole (7) at the top of the head being 0.3 to 1.1 mm, the axial distance between the center lines of the first total pressure hole (7) and the second total pressure hole (7) at the bottom of the head being 0.3 to 1.1 mm, and the axial distance between the center lines of the remaining two adjacent holes being 0.5 to 1.2 mm; the axial distance from the center line of the total pressure hole at the top and the bottom of the head to the end is 0.5 to 1 mm, the center line directions of the total pressure holes are not exactly the same, and are distributed within a range of 180°, and the center lines of the first total pressure hole and the last total pressure hole are parallel;

[0017] Furthermore, the total pressure hole (7) adopts a smooth transition of a micro-loss convergent surface, and the profile curve of the surface satisfies the following equation:

[0018]

[0019] In the formula, R2 is the outlet radius, L is the length of the inlet section of the pressure measuring hole, R1 is the inlet radius, and x m is the coordinate of the connecting point between the front and back segments, x m Select 0.3.

[0020] The inlet diameter of the micro-loss convergence surface is 0.2-0.5 mm, the outlet diameter of the micro-loss convergence surface is 0.1-0.25 mm, the outlet of the micro-loss convergence surface is connected to the sensor cable lead-out channel (12), the pressure sensing hole has a diameter of 0.1-0.2 mm, and the pressure sensing hole is connected to the sensor cable lead-out channel (12);

[0021] Furthermore, the total temperature hole (9) is a truncated cone-shaped hole opened on the cylindrical surface of the head, the diameter of the hole inlet is 0.4-0.8 mm, the diameter of the hole outlet is 0.5-0.6 times the diameter of the inlet, and the hole outlet is connected to the sensor cable lead-out channel (12);

[0022] Furthermore, the front end of the temperature sensor (6) is flush with the cylindrical surface of the head, and is fixed in the temperature measuring hole by a heat-insulating seal (10). The front end of the pressure sensor in the total pressure hole (7) is flush with the outlet of the micro-loss convergence surface. The distance between the pressure sensor in the pressure sensing hole and the inlet of the pressure sensing hole is 0.5 to 1.5 mm. The temperature sensor cable and the pressure sensor cable are led out through the sensor cable lead-out channel (12) inside the probe.

[0023] Furthermore, the diameter of the head (1) is 2 to 6 mm, and the diameter of the sensor cable lead-out channel (12) is 0.5 to 0.6 times the diameter of the head (1);

[0024] Furthermore, the temperature sensor (6) may be a thermal resistor, a thermocouple or an optical fiber temperature sensor;

[0025] Furthermore, after wind tunnel calibration, calibration and data processing, a multi-point dynamic full-parameter measurement device for a subsonic two-dimensional flow field of the present invention can simultaneously realize multi-point dynamic measurement of full parameters such as total temperature, total pressure, static temperature, static pressure, Mach number, deflection angle, speed, density, etc., and has high total temperature and total pressure measurement accuracy.

[0026] The advantages and positive effects of the invention are:

[0027] Beneficial effect 1: Compared with the prior art, the temperature sensor of the present invention faces away from the mainstream and is located in the low-speed separation zone on the leeward side of the head. First, the scouring of the temperature sensor by the airflow is reduced, and the influence of oil droplets, dust, etc. mixed in the airflow on the temperature sensor is reduced, thereby effectively improving the service life of the temperature sensor; second, the strength requirement for the temperature sensor is relatively low, and the size of the temperature sensor can be relatively small, thereby effectively reducing the size of the head. In addition, the back-to-back arrangement of the total temperature hole and the total pressure hole can make full use of the space, which is also conducive to reducing the size of the head. Therefore, its spatial resolution is high; third, the range of the separation low-speed zone is relatively large, and the opposing vortices in the separation zone effectively enhance the heat exchange between the airflow and the temperature sensor. Therefore, the temperature recovery coefficient is high and stable within a larger deflection angle range during measurement; fourth, the temperature sensor is placed in the flow field, and there is no obstruction between the flow field and the temperature sensor, so its response time is fast; fifth, the front end of the temperature sensor of the present invention is flush with the cylindrical surface of the head, that is, the measuring point where the temperature sensor is located is located exactly on the cylindrical surface of the head, which can make full use of the flow characteristics of the head and realize accurate temperature measurement.

[0028] Beneficial effect two: The head of the present invention is provided with multi-point total temperature holes and a "three-hole structure" for pressure measurement. The total temperature holes are distributed at 180° to the total pressure holes and their center lines are collinear. The total temperature measured by the total temperature holes and the total pressure measured by the total pressure holes are on the same streamline. Both the temperature sensor and the pressure sensor are dynamic sensors. Therefore, the present device alone can realize multi-point synchronous dynamic measurement of full parameters such as total temperature, total pressure, static temperature, static pressure, Mach number, deflection angle, speed, density, etc. For multi-point full-parameter measurement of complex unsteady flow fields, there is no need to install temperature probes and pressure probes separately to realize full-parameter measurement, nor is there a need to use a probe displacement mechanism to drive the probe to measure separately at different blade height positions, thereby saving test time.

[0029] Beneficial effect three: The total pressure hole of the present invention adopts a smooth transition of a micro-loss convergent surface. Compared with the straight transition section of the existing dynamic total pressure probe, it can reduce the total pressure loss and flow separation when converging within a wider deflection angle range, thereby improving the accuracy of total pressure measurement. The total temperature hole adopts a truncated cone-shaped hole, which can have a high and stable temperature recovery coefficient within a larger deflection angle range, which is beneficial to enhancing the convective heat exchange between the airflow and the temperature sensor.

[0030] Beneficial effect four: Temperature drift is one of the main reasons for the measurement error of the pressure sensor. The zero-point output voltage of different pressure sensors changes with temperature and their changing trends and amplitudes are different. The device of the present invention can measure the total temperature and static temperature parameters, and the total temperature hole and the total pressure hole are distributed at 180° to each other and the center lines are collinear. The parameters measured by the temperature sensor and the pressure sensor are the parameters of the same streamline, and the zero-point drift of the pressure sensor used can be corrected by temperature, thereby ensuring the accuracy of the pressure measurement.

[0031] Beneficial effect five: The head size of the present invention can be very small, so it can also be used for boundary layer parameter measurement. Because the present invention can simultaneously realize the dynamic measurement of all parameters such as total temperature, total pressure, static temperature, static pressure, Mach number, deflection angle, speed, density, etc. and has high total temperature and total pressure measurement accuracy, when using the present invention to measure boundary layer parameters, there is no need to use multiple probes to measure multiple times to obtain the full parameters of the flow field, thereby reducing interference with the thinner boundary layer. The present invention realizes the dynamic measurement of all parameters of the boundary layer. Therefore, dynamic full parameter measurement can be realized for the complex flow boundary layer caused by the rotation of the rotor, the staggered arrangement of the moving and static blade rows, and the leakage flow of the blade tip gap.

[0032] The present invention has the following advantages: using the device of the present invention alone can simultaneously realize multi-point dynamic measurement of all parameters such as total temperature, total pressure, static temperature, static pressure, Mach number, deflection angle, speed, density, etc., and has high total temperature and total pressure measurement accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a front view of the structure of the probe embodiment 1 of the present invention.

[0034] Figure 2 It is a rear cross-sectional view of the structure of the probe embodiment 1 of the present invention.

[0035] Figure 3 It is a partial enlarged view of the total pressure hole and total temperature hole structure of the probe embodiment 1 of the present invention.

[0036] Figure 4 It is a schematic diagram of the AA cross-section of the structure of the probe embodiment 1 of the present invention.

[0037] Figure 5It is a definition diagram of the total pressure hole profile curve in the first embodiment of the probe of the present invention.

[0038] Figure 6 It is a schematic diagram of the installation of the device in the first embodiment of the present invention.

[0039] Figure 7 It is a front view of the structure of the probe embodiment 2 of the present invention.

[0040] Figure 8 It is a rear cross-sectional view of the structure of the probe embodiment 2 of the present invention.

[0041] Fig. 9 It is a partial enlarged view of the total pressure hole and total temperature hole structure of the probe embodiment 2 of the present invention.

[0042] Fig.10 It is a schematic diagram of the AA cross-section of the structure of the probe embodiment 2 of the present invention.

[0043] Fig.11 It is a definition diagram of the total pressure hole profile curve in the second embodiment of the probe of the present invention.

[0044] Fig.12 It is a schematic diagram of the installation of the device in the second embodiment of the present invention.

[0045] The markings and corresponding parts and surface names in the accompanying drawings include: 1-head; 2-transition section; 3-support rod; 4-pressure sensor cable; 5-temperature sensor cable; 6-temperature sensor; 7-total pressure hole; 8-pressure sensing hole; 9-total temperature hole; 10-insulating seal; 11-pressure sensor; 12-sensor cable lead-out channel. DETAILED DESCRIPTION

[0046] The present invention is described in detail below in conjunction with the accompanying drawings and embodiments, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0047] Embodiment 1:

[0048] The present invention can be applied to the dynamic measurement of all parameters at multiple points along the radial direction of the engine inlet. In this case, evenly distributed measuring points can be selected. When installing the engine inlet, due to the small installation space limitation and considering the probe strength, a slightly larger probe structure can be selected. The installation diagram is shown in FIG. Figure 6 The selected structural scheme is as follows:

[0049] like Figure 1 , Figure 2 , Figure 3 , Figure 4As shown, this embodiment introduces a multi-point dynamic full-parameter measurement device for a subsonic two-dimensional flow field, comprising a head (1), a transition section (2), and a support rod (3). The head (1) and the support rod (3) are both cylindrical. A total pressure hole (7) is opened on the windward surface of the head (1). The center line of the total pressure hole (7) is perpendicular to the center line of the head (1). There is a pressure sensing hole (8) on each side of the total pressure hole (7). The total pressure hole (7) and the pressure sensing holes (8) on both sides thereof are at an angle of 15°. The total pressure hole (7) and the pressure sensing holes (8) on both sides thereof are at an angle of 15°. The center lines of the pressure sensing holes (8) on the side are on the same plane, forming a three-hole structure. A total temperature hole (9) is opened on the leeward side of the head (1). The total temperature hole (9) and the total pressure hole (7) are 180 degrees apart and their center lines are collinear. The temperature sensor (6) is located in the total temperature hole. The total pressure hole (7) and the pressure sensing hole (8) are each encapsulated with a pressure sensor (11). A sensor cable lead-out channel (12) is opened on the head of the device. The pressure sensor cable (4) and the temperature sensor cable (5) are led out from the tail of the device through the channel.

[0050] In this embodiment, the five three-hole structures and the five total temperature holes (9) are distributed at different axial positions along the head (1), and the distribution pattern can be uniform distribution. The axial distance between the center lines of two adjacent holes is 0.4 mm, and the axial distance from the center line of the top and bottom total pressure holes of the head to the end is 0.5 mm. The center line directions of the total pressure holes are different and are distributed within a range of 180°. The center lines of the first total pressure hole and the last total pressure hole are parallel.

[0051] The total pressure hole (7) adopts a smooth transition with a micro-loss convergent surface. Figure 5 is the definition diagram of the profile curve. The profile curve of the surface satisfies the following equation:

[0052]

[0053] In the formula, R2 is the outlet radius, L is the length of the inlet section of the pressure measuring hole, R1 is the inlet radius, and x m is the coordinate of the connecting point between the front and back segments, x m Select 0.3.

[0054] The inlet diameter of the micro-loss convergence surface is 0.3 mm, the outlet diameter of the micro-loss convergence surface is 0.15 mm, the outlet of the micro-loss convergence surface is connected to the sensor cable lead-out channel (12), the pressure sensing hole has a diameter of 0.15 mm, and the pressure sensing hole is connected to the sensor cable lead-out channel (12);

[0055] The total temperature hole (9) is a truncated cone-shaped hole opened on the cylindrical surface of the head, the diameter of the hole inlet is 0.5 mm, the diameter of the hole outlet is 0.5 times the diameter of the inlet, and the hole outlet is connected to the sensor cable lead-out channel (12);

[0056] The front end of the temperature sensor (6) is flush with the cylindrical surface of the head, and is fixed in the temperature measuring hole by a heat-insulating seal (10). The front end of the pressure sensor in the total pressure hole (7) is flush with the outlet of the micro-loss convergence surface. The distance between the pressure sensor in the pressure sensing hole and the inlet of the pressure sensing hole is 1 mm. The temperature sensor cable and the pressure sensor cable are led out through the sensor cable lead-out channel (12) inside the probe.

[0057] In this embodiment, the diameter of the head (1) is 4 mm, and the diameter of the sensor cable lead-out channel (12) is 0.5 times the diameter of the head (1);

[0058] In this embodiment, the temperature sensor (6) may be a thermal resistor, a thermocouple or an optical fiber temperature sensor.

[0059] Embodiment 2:

[0060] The present invention can be applied to the dynamic measurement of total temperature, total pressure, static temperature, static pressure, Mach number, deflection angle, speed, density and other parameters at multiple points along the blade height direction between compressor stages. The installation diagram is shown in FIG. Fig.12 As shown, the airflow direction along the blade height direction between engine stages is very different, and the deflection angle of the local airflow will exceed the insensitive angle of the probe measurement, resulting in a large measurement error. At the tip and root of the blade, close to the boundary layer, the total pressure gradient is very large, so it is necessary to select a distribution method where the total pressure holes are dense on both sides and sparse in the middle. The head diameter should also be selected to be smaller, on the one hand, to facilitate installation in the narrow area between the blade rows, and on the other hand, to minimize the impact on the boundary layer. The selected probe structure scheme is as follows:

[0061] like Figure 7 , Figure 8 , Fig. 9 , Fig.10 As shown, this embodiment introduces a multi-point dynamic full-parameter measurement device for a subsonic two-dimensional flow field, comprising a head (1), a transition section (2), and a support rod (3). The head (1) and the support rod (3) are both cylindrical. A total pressure hole (7) is opened on the windward surface of the head (1). The center line of the total pressure hole (7) is perpendicular to the center line of the head (1). There is a pressure sensing hole (8) on each side of the total pressure hole (7). The total pressure hole (7) and the pressure sensing holes (8) on both sides thereof are at an angle of 15°. The total pressure hole (7) and the pressure sensing holes (8) on both sides thereof are at an angle of 15°. The center lines of the pressure sensing holes (8) on the side are on the same plane, forming a three-hole structure. A total temperature hole (9) is opened on the leeward side of the head (1). The total temperature hole (9) and the total pressure hole (7) are 180 degrees apart and their center lines are collinear. The temperature sensor (6) is located in the total temperature hole. The total pressure hole (7) and the pressure sensing hole (8) are each encapsulated with a pressure sensor (11). A sensor cable lead-out channel (12) is opened on the head of the device. The pressure sensor cable (4) and the temperature sensor cable (5) are led out from the tail of the device through the channel.

[0062] In this embodiment, the five three-hole structures and the five total temperature holes (9) are distributed at different axial positions along the head (1), showing a distribution pattern of sparse in the middle and dense on both sides. The axial distance between the center lines of the first total pressure hole (7) and the second total pressure hole (7) at the top of the head is 0.3 mm, the axial distance between the center lines of the first total pressure hole (7) and the second total pressure hole (7) at the bottom of the head is 0.3 mm, and the axial distance between the center lines of the remaining two adjacent holes is 0.5 mm; the axial distance from the center line of the total pressure hole at the top and the bottom of the head to the end is 0.5 mm, the center line directions of the total pressure holes are different, distributed within a range of 180°, and the center lines of the first total pressure hole and the last total pressure hole are parallel;

[0063] The total pressure hole (7) adopts a smooth transition with a micro-loss convergent surface. Fig.11 is the definition diagram of the profile curve. The profile curve of the surface satisfies the following equation:

[0064]

[0065] In the formula, R2 is the outlet radius, L is the length of the inlet section of the pressure measuring hole, R1 is the inlet radius, and x m is the coordinate of the connecting point between the front and back segments, x m Select 0.3.

[0066] The inlet diameter of the micro-loss convergence surface is 0.2 mm, the outlet diameter of the micro-loss convergence surface is 0.1 mm, the outlet of the micro-loss convergence surface is connected to the sensor cable lead-out channel (12), the pressure sensing hole has a diameter of 0.1 mm, and the pressure sensing hole is connected to the sensor cable lead-out channel (12);

[0067] The total temperature hole (9) is a truncated cone-shaped hole opened on the cylindrical surface of the head, the diameter of the hole inlet is 0.4 mm, the diameter of the hole outlet is 0.5 times the diameter of the inlet, and the hole outlet is connected to the sensor cable lead-out channel (12);

[0068] The front end of the temperature sensor (6) is flush with the cylindrical surface of the head, and is fixed in the temperature measuring hole by a heat-insulating seal (10). The front end of the pressure sensor in the total pressure hole (7) is flush with the outlet of the micro-loss convergence surface. The distance between the pressure sensor in the pressure sensing hole and the inlet of the pressure sensing hole is 0.5 mm. The temperature sensor cable and the pressure sensor cable are led out through the sensor cable lead-out channel (12) inside the probe.

[0069] In this embodiment, the diameter of the head (1) is 2 mm, and the diameter of the sensor cable lead-out channel (12) is 0.5 times the diameter of the head (1);

[0070] In this embodiment, the temperature sensor (6) may be a thermal resistor, a thermocouple or an optical fiber temperature sensor.

[0071] Although the preferred embodiment has been described, various modifications or substitutions may be made to the embodiment without departing from the spirit and scope of the invention. Therefore, it should be understood that the present invention has been described in an illustrative manner rather than a restrictive manner.

Claims

1. A method for using a multi-point dynamic full-parameter measurement device for measuring subsonic two-dimensional flow fields to realize full-parameter dynamic measurement of multiple points along the blade height direction of an aircraft engine inlet and an impeller machinery inlet and outlet and between blade rows. The structure of the multi-point dynamic full-parameter measurement device for measuring subsonic two-dimensional flow fields is as follows, characterized in that: The device comprises a head (1), a transition section (2), and a support rod (3). The head (1) and the support rod (3) are both cylindrical. A total pressure hole (7) is provided on the windward surface of the head (1). The center line of the total pressure hole (7) is perpendicular to the center line of the head (1). There is a pressure sensing hole (8) on each side of the total pressure hole (7). The total pressure hole (7) and the pressure sensing holes (8) on both sides thereof are at an angle of 15° to 16°. The center lines of the total pressure hole (7) and the pressure sensing holes (8) on both sides thereof are on the same plane, forming a three-hole structure. A total temperature hole (9) is provided on the leeward surface of the head (1). The total temperature hole (9) and the total pressure hole (7) are 180° apart and their center lines are collinear. A temperature sensor (6) is located in the total temperature hole. A pressure sensor (11) is respectively encapsulated in the total pressure hole (7) and the pressure sensing hole (8). A sensor cable lead-out channel (12) is provided on the head of the device. The pressure sensor cable (4) and the temperature sensor cable (5) are led out from the tail of the device through the channel. At least five of the three-hole structures and five total temperature holes (9) are distributed at different axial positions along the head (1), and the distribution pattern is uniform distribution, and the axial distance between the center lines of two adjacent holes is 0.3-0.9 mm; or the distribution pattern is sparse in the middle and dense on both sides, the axial distance between the center lines of the first total pressure hole (7) and the second total pressure hole (7) at the top of the head is 0.3-1.1 mm, the axial distance between the center lines of the first total pressure hole (7) and the second total pressure hole (7) at the bottom of the head is 0.3-1.1 mm, and the axial distance between the center lines of the remaining two adjacent holes is 0.5-1.2 mm; the axial distance from the center line of the total pressure hole at the top and the bottom of the head to the end is 0.5-1 mm, the center line directions of the total pressure holes are different, and are distributed within a range of 180°, and the center lines of the first total pressure hole and the last total pressure hole are parallel; The total pressure hole (7) adopts a smooth transition of a micro-loss convergent surface, and the profile curve of the surface satisfies the following equation: In the formula, R2 is the outlet radius, L is the length of the inlet section of the pressure measuring hole, R1 is the inlet radius, and x m is the coordinate of the connecting point between the front and back segments, x m Select 0.3; The inlet diameter of the micro-loss convergence surface is 0.2-0.5 mm, the outlet diameter of the micro-loss convergence surface is 0.1-0.25 mm, the outlet of the micro-loss convergence surface is connected to the sensor cable lead-out channel (12), the pressure sensing hole has a diameter of 0.1-0.2 mm, and the pressure sensing hole is connected to the sensor cable lead-out channel (12); The total temperature hole (9) is a truncated cone-shaped hole opened on the cylindrical surface of the head, the diameter of the hole inlet is 0.4-0.8 mm, the diameter of the hole outlet is 0.5-0.6 times the diameter of the inlet, and the hole outlet is connected to the sensor cable lead-out channel (12); The front end of the temperature sensor (6) is flush with the cylindrical surface of the head, and is fixed in the temperature measuring hole by a heat-insulating seal (10). The front end of the pressure sensor in the total pressure hole (7) is flush with the outlet of the micro-loss convergence surface. The distance between the pressure sensor in the pressure sensing hole and the inlet of the pressure sensing hole is 0.5 to 1.5 mm. The temperature sensor cable and the pressure sensor cable are led out through the sensor cable lead-out channel (12) inside the probe. The diameter of the head (1) is 2 to 6 mm, and the diameter of the sensor cable lead-out channel (12) is 0.5 to 0.6 times the diameter of the head (1); The temperature sensor (6) is a thermal resistor, a thermocouple or an optical fiber temperature sensor; The use steps are as follows: Step 1: calibrate the probe through a calibration wind tunnel to obtain the probe calibration curve; The second step: obtaining the calibration coefficient curve and formula based on the data measured by the three pressure sensors and temperature sensors at each axial position and the probe calibration curve; the third step: inserting the device of the present invention into the measured flow field when in use to realize full-parameter dynamic measurement of multiple points along one direction of the aircraft engine inlet duct and full-parameter dynamic measurement of multiple points along the blade height direction between the impeller machinery inlet, outlet and blade rows.

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